I have an old frame here to experiment with. I set it up 1x8 with an 11-32 cassette and rode it for about a month with no problems. Since I'm in flat Florida, today I said, the heck with it and switched it with a 12-21 I had laying around. Same long cage RD. Surprisingly, it works like a charm!
Dude your videos are fantastic! I'm doing up a old 1987 Raleigh Criterium 12 Triathlon by putting modern groupset on it. Now I'm a novice at all this but every time I think of a question you have the answer! From big jobs like fitting a 10 speed cassette to things like this video. It's so helpful and can't thank you enough :)
The typical bicycle shop mechanic is only able to assemble and replace parts with identical components. They do not understand properties of materials or design of mechanical assemblies. Walk into your local shop carrying a micrometer and watch their faces change from confidence to confusion or belligerence. The man in these videos is above average and any contradiction to his words by the local guy is a sign to walk away….push that bike to another shop.
Very interesting. Thank you for pointing out how to determine whether a cogset/chainring set will work with a rear derailler before purchasing it. This is a big help for anybody planning to change either their derailler or cogs or chainwheels to a different size.
Phew, this saved me 60 bucks, thank you. Was about to buy a short cage for my 2x10 with 11/36 T Rear + 24/38 T Front. Found out I needed a Long gage so I'm glad you had this vid up :D
David, yet again, this video was SUPERB. I did find it extremely useful, in answer to your concerns to the viewer at the end of the video. Thank you so much Sir!
Sorry "RJ", I made a mistake as I misperceived a big huge "D" symbol framed in red (next to David James) as being the symbol for the OP. I had addressed my initial messages to you "RJ", but on seeing this, I respectfully re-edited my post, with albeit the 'wrong' address. It was a simple mistake, and no offense was meant. I apologise for this.
Love your videos! I've never had this explained more thoroughly, and FINALLY understand the difference and how to determine which derailleur to use. Thanks, RJ
I see you have the slx mech , I swapped my old xt mech for one of those and what a big difference it made , the gear changes are so crisp and smooth , very highly recommended :) , another very informative video RJ
I'm using Claris long cage derailleur and its coverage is excellent upto 32t cog. I can upgrade to 2x9 speed later just by changing the shifters and chain~
In my country, the country I come from the chain length variation is calculated using a different method yet comes out with the same result. Add the two largest and two smallest possible sets and subtract the smaller number from the larger one. (They call me “Largest Cog”)
I have a double chainring 50/34 and an 8speed cassette 11-28 on a older road bike. I was told that I need to use a long cage. It's a direct mount if that makes any difference? They suggested a Shimano Acera.
A long cage, where it is not needed, will cause a lot of chain slap, unless you have a clutch. It can cause you to lose your chain in rough terrain or over common street obstacles like speed bumps and pot holes. Shorter cage deraileurs do tend to shift faster, quieter and smoother, partly because you get better chain wrap and the guide wheel closer to each cog, but also because there isn't so much to flex (it isxastounding how long a short cage deraileur can stay in adjustment vs a long). These are all niggling things until you apply them to 1x vs triples, with huge range. Also, any e-bike. E-bikes can have problems with power over run with motor inhibitors between shifts, oh and cheaper ones (most) often have sticky freewheels instead of cassettes. Now all that extra chain slop bunches up and causes all sorts of problems.
I have a Shimano Deore LX "9-speed" rear derailer on my bike. It is rated at 45 total capacity, but I am running it at 47 with no problem. 47=(48-24)+(34-11) I don't think it could handle even one more tooth, but at 47, it works fine. This derailer is also rated at 34 for the largest cog, but I know people have run it with 12-36 cassettes. I have also read of people making it work with 10-speed cassettes. Moral: Shimano can be a bit conservative with their ratings. Sometimes you can get away with a little bit more.
When I say it works fine, I mean it can handle both the big-big and the small-small combinations and everything in between. Some people set up a bike with more capacity than the derailer can handle and get away with it by never selecting the big-big or small-small combinations. That is not what I am doing.
Here is a picture with the gears in the small-small position. picasaweb.google.com/113065978323692444332/BikeBits#5587747131539541730 Here is a picture with the gears in the big-big position. picasaweb.google.com/113065978323692444332/BikeBits#5587747274927222978
My opinion: The Shimano Deore M591 SGS rear derailer may be the best, general purpose, rear derailer ever made. Rated Capacity = 45, Practical Capacity = 47, Rated Large Cog = 34, Practical Large Cog = 36. Will easily work with 7-9 cogs and can be used with 10, with the right setup. All the parts that should be metal are metal. This derailer is perfect for a wide range of bike trails, touring, commuting,etc. The derailer in my pictures is an extremely similar Deore LX. My wife's bike has the M591. The LX is only cosmetically different from the M591. The other good thing about the M591? It costs less than most of Shimano's decent quality line.
Basically if you're not sure, you should ask your local bike shop. I have road bikes that I want to run larger cassettes on because I live in really hilly area and I need to find out what I need to get to do it.
Would I be able to use a 26/13 cassette in place of a 32/11 cassette which I already have along with a Shimano Sora derailuer already fitted to my rear wheel
I have the SRAM APEX. It is compatible with max. 32T (biggest cog on the cassette) and is a mid cage type of thing. Mounted a 36T and didn`t know what the problem was before finally grasping the nature of the issue. I never knew there was a limit for these things. Guess you live and learn.
My derailleur has a 28T maximum capacity (largest sprocket: 28T) but I calculated a difference of 34T in my gear range. My bike came like that from the factory. Would it help if I put a derailleur that has a maximum capacity of 30T (largest sprocket: 30T)? And would I be able to ditch the 14x28 tooth for something with a larger gear range like a 14-34T? I never go in, for example, 1-6 or 3-1.
The amount of chain the RD will take up and the largest cog it can handle are two different things. Generally you can go a little larger with the cog size. But don't exceed the capacity.
Thanks for the great video - I know it's old, but this problems is still occurring g today. Now, my drivetrain has changed with the latest upgrade and I need your help understand exactly if a Medium Cage will work. Old Drivetrain - 3 by 7 : Front 3 rings (42, 36, 29T) Rear: 7 rings (11 to 36T) New Drivetrain - 1 by 10 : Front 1 ring 32 T, Rear 10 rings (11 to 46T) Do I need a Long Cage for my New Drivetrain, or a Medium Cage should be enough?
I found this very useful . I have a Fuji Absolute 2.3 but it's set up for a seven speed but it has a Shimano HG 9 speed cassette . I'm just wondering what derailleur to look for n shifters for it as well . I would like to get rid of the front derailleur n go with a 1x drivetrain . Any thoughts or suggestions would be great . New subscriber . Thanx again
Hi RJ, i have a 2015 GT grade with Shimano Claris. I'm looking to replace the rear derailleur from a short cage to a long cage, this way i can use a 11-34 o 11-36 cassette. Can a use a Shimano mtb rear derailleur with road claris levers? Thank you
Thanks for your videos! I am wondering if this is the reason why my rear derailleur does not shift to the smallest cog when using the biggest chainring? 🤷♂️ I am using an older gen Shimano 600 Groupset (Friction shifters) but testing with a 9 speed Miche Cassettte. (I think it is 13-26 though) and new KMC 9 speed chain. if I shift from the big chainring to the small, the derailleur then will shift to the smallest cog automatically..
Another amazing content RJ. Your online presence is truly valued. Question though, what's your take on using a rear mech on a drivetrain beyond its spec sheet capacity? Just installed an 11-32 10 speed sprocket using a 5701 SS. I'm 2 teeth over the largest cog and 9 teeth over the capacity. I really do not ride cross-chained, will I have problems in the future?
+Gian Tan The specs are *slightly* conservative. The largest cog spec especially. You can usually go a couple teeth over the largest cog spec with no problems. 9 teeth over capacity? I would be VERY leery of that. If you accidentally shift into too big of a combination you can maybe have some major problems. Maybe destroy the derailleur and who knows what else.
+RJ The Bike Guy Who knows what else may involve snapping my hanger feeding my rear mech into my rear wheel and tip me over face first. Yes I will be very very leery of that. Hehe. Though even running 11-28 before I have never had the habit of using bad combinations.
+RJ The Bike Guy One last thing RJ if its okay. I fitted my chain to accommodate a big-big combination. Some slack will be expected in small-small but, again, I will never ride in both combinations. Do you think the chain length I used will help minimize risks from the over capacitated rear mech?
+RJ The Bike Guy Medium cages are hard to come by in my area. Pretty much all the shops here have mid cages for 11 speed. I can go with Sora which have higher rated capacity but shifting may be a dud. But I am on an on going hunt for a GS 105 or even a 4700 mid cage.
I changed out the wide range freewheel on a 96 Gary Fisher (bought on CL) for a narrow range also changed out the 42T chainring for a 44T. Can and should I change out the long cage for a short cage without getting a new deraillur?
Chain length should be set so you can shift cleanly onto the big sprocket when it's on the big ring. Then shift to the small ring and sprocket: the derailleur should still be applying tension to the chain. There's more to it if the derailleur has "A" and "B" tension screws.
Good video, I’m doing a project bike and not sure if the derailleur is too big. It has 12 inch wheels (can’t go any bigger) and I don’t want it scraping the floor, how can I measure it? And if it doesn’t fit, what should I do? Are there small enough derailleurs to fit? (I saw one on a 12 inch folding bike but I can’t find that model anywhere. I don’t need much range.
Hey RJ.. Could you go over an adapter for the RD hanger that allows the B screw to adjust in far enough that keeps the upper jockey wheel from rubbing the small clog if the B screw is NOT long enough for the adjustment. I've heard of this but not sure what to buy. I have a older Shimano DA onto a new TRek Emonda SL.
Great question.. that answer could be different on who you ask. Im running a Compact 50/34 and 12 -30 Cassette with short cage Shimano Durs ace RD. Shimano says 28T is max but I know from experience you can run a 30T. Climbed 9000 feet over the weekend and a mechanic I ran into said I could buy an adapter or longer B screw to keep it off the upper jockey wheel. The new RD hanger on the Trek doesn't line up very well with the B screw on the older RD. That's when he mention note of the adapter, Thoughts?
another good video , thank you lemme ask u, if i changed my front chain ring to be only one instead of 2 it had and didn't touch the rear sprockets \i kept the same 6 it had, would i still apply the same math operation you did or would it change somewhat. thanks again
Im a slacker with megarange. My derailleaur was damaged and is no longer available. Tx 31 shimano.tourney. Any suggestions. I got a ty 500 and it did not work. Unless i change crankset and shorten chain. Not gonna happen. I would think megarange derailleaurs would work. A lot of times even though it has more gears... I set it up for the gears i use. One up front and a couple in the back and a mega gear. Thats it. But most bikes i get have way more crap than i use....and that usually is the intent. Use defines purpose. A couple of gears...not 24 speeds. I just need a couple and an extreme uphill. Whats with the sprocket madness.
Simple solution is buy a used Megarange derailleur on eBay. Serious cyclists know where their power range is. They are most efficient pedalling in certain cadence ranges (ie 90-100rpm). More gears allows them to stay in that cadence range at different speed/terrains.
@@RJTheBikeGuy sun damaged plastic are brittle. Crumble to dust. Plastic don't last. I used to used old CD. Cut hole in the middle. But that do not work well, cause it is flat. Need cone shape to match spoke angle. So I cut sheet mtl to circular shape. Hammer it flat. Watch lots tutorial on sheet metal cold forming. It is possible to DIY spoke protector from sheet metal or metal bottle. Actually pretty easy and fun to make. Can even make it from giant beer can or all the Pepsi can you have in your garage. But not as good looking as $3 new plastic spike protector or alum mass production spoke protector. But one of the kind. Signature mount on bike. No one can steal the bike. Have you make one before?
@@RJTheBikeGuy I did not know what it is for before. Ride without it. And broke the spoķe. Fly spoke protector from everyday materials. Have u made one ?
Hey rj I have a mtb with a single 30t in front and 11-34t in the rear. I'm looking to get a short cage to lessen chance of hitting it. Any recommendations? I can't seem to find anything. Using Shimano shifters. 9 speed. Thanks!
nice video man learnt alot from this 1 video, i do have a question tho what isa the best value for money mountain bike on the market now hard tail or full sus with a single front drive chain with a rear cassette thanks man
Can you convert a 14-28 tooth 6 speed freewheel to a 14-34 tooth 6 speed freewheel (if yes, how about a 11-34 tooth 7 speed or a 13-34 tooth 7 speed) without changing the derailleur? Mine is an old model shimano TY18 derailleur. Great video!
Is it possible to determine the capacity of a derailleur without refering to it's instruction sheet (eg, measuring cage length, jockey wheel diameters)?
Hello, very good video! What are the consequences if a new rear cassette brings the derailleur beyond its total capacity, my chain is sliding along the teeth on the smallest cog when there is pressure applied to the peddles, especially at the beginning of a hill. I have a dura ace RD7800(29 or less total capacity) and the new cassette is a 7900 11-27 ratio, with a 39-53 front ring? Thank you in advance
Don't forget...If you go to a much smaller cassette...say 11/25 from a 11/36 and you have a long cage, It may not shift very well because the derailleur B setting is too far from the 25T cog. That's the problem I have now. So I'm going to use a 11/28 and get a short derailleur.
When you count the difference in teeth between the smallest and largest cogs and then report that to the chain, should not that number be divided by roughly 2? After all, the chain only goes around half of the chainring/sprocket.
David, could I ask you, in your expert opinion: I have got a triple 32-42-52 front and a 21/13T rear block. Should I get a short cage or long cage? My chain wrap value is 28... But, due to mechanical sympathy on my part, I am *not* going to be using anything more than *4* sprockets on the back with any of the front cranks. By this I mean, the: 32 front paired with 21,19,17,15 42 front paired with 19,17,15,14 52 front paired with 17,15,14,13 So, how does that change things? And as I've heard that a short-cage gives a quicker, more precise shit, would a short cage actually do me? One last question, if I wanted to put on a 7 or 8 speed block when the 6 speed wears out, I would go *only* as a far as a 23 rear sprocket. If an 8 speed, it would mean 23/12 (maybe). Would the same short cage fit this too, bearing in mind that I would be leaving out extremes of chain-crossing? Anyway, the 1st question is obviously far more important for now. Any advice you can give me would be extremely appreciated. Thanks and God bless :)
I explained exactly how to figure it out in the video. And going from 6 to 7/8 speeds is probably not going to be as easy as just swapping out freewheel/cassette. It gets into hubs widths, shifter compatibility, etc, but that's a whole other issue.
Thank you RJ. As already posted, I did say your video was very useful, and sincerely thanked you for it. However, the chain wrap capacity value which you outlined in your video appeared to just cover the extremes of combinations e.g. big ring with big sprocket. As I don't cross-chain like this, I was wondering shouldn't the equation be changed to reflect this? I only ask as considering that my chain wrap capacity is on a borderline '28' going on a full chain-crossing calculation (i.e. 52-32, and 21-13). And I would rather stay short cage as I've 'heard' that they are a bit more precise and quicker shifting than longer cages. I have tried many other fora, but can't seem to get an answer on it. I ask you, as you seem very obliging by your demeanour on screen, knowledgeable, and because you go to the trouble of producing lovely videos for the purpose of educating and helping people with no apparent financial motives. If my asking still offends you, I understand and apologise sincerely for same.
You have to take into account ALL the combinations. It's easy to say you never cross-chain, up to the point where you accidentally shift into that combination and destroy your derailleur, take out your rear wheel, crash and die. You can do what you want, but I recommend very strongly to take into account the full range of possible gear combinations as I do in the video.
RJ I don't know why you have to be so confrontational and ungentlemanly. I did apologise and have been nothing but cordial to you since. You seem to want to help people with your many videos, yet you can't seem to take an innocent mistake and subsequent apology with good grace?
I have a cheap Walmart mountain bike (Hyper Summit) which came with 24-34-42 in front and 28-24-22-20-18-16-14 in back so I would assume that is a medium cage since the range of teeth is medium (18 up front and 14 in rear). The bike came with Shimano derailleurs. I want to go to a Shimano MegaRange gear in the back which replaces the 28 with a 34. I will also try to replace my 24 granny chainring with 20. So I will have added 10 more teeth of possible range to the total system but to help with not exceeding any limits, I can simply never use the largest chainring with the largest cog and never use the smallest chainring with the smallest cog.... Just because I widen the range of teeth doesn't mean I have to use them. I guess the only way to know if my gear mods will work is to try them.
+RJ The Bike Guy - I looked in the owners manual and it doesn't mention any specifications about the derailleurs. When I look on the actual rear derailleur, it just has Shimano on it but I don't see any model number or any other markings. Any advice on how I can figure out which model it is? The bike is a new model (introduced within the past 6 months) called Hyper Summit.
RJ The Bike Guy - Yes you are right. It is the Shimano tourney RD-TZ31 rear derailleur. it was very hard to see but when I used a flashlight at the correct angle, I could see it. Thank you! Unfortunately for me the specs online say it maxes out at 28T cog and I want to put a 34T on there. Also my dropouts appear to be 135mm inside diameter between them so should I consider an upgrade to maybe an 8 or 9 speed freewheel if I will be upgrading the RD anyway?
You could maybe put a 30T cog on there. I wouldn't try pushing it to 34 though. 135mm is mountain bike spacing. Frankly I wouldn't spend any money upgrading a Walmart bike.
Very good, easy to understand explanation. If I'm going with a 1x10 drivetrain on a mountainbike (11-32?), I'm assuming a short or medium cage is fine, that the calculation is simply "32 minus 11" or "21". Anything else that I should consider in going 1x__ drivetrain? Thanks again... so good a video that I didn't mind being flipped off. :-)
Probably. FD's also come in road bike or mount bike flavors. There are also different clamp sizes, or even braze on models. And then they are also top pull or bottom pull..
Nice video. Question: Scenario ... Only one front sprocket (30T) and rear cog set of 11T - 34T, 8 Speed. How do you make the calculation for Long Cage/Short Cage ? Or will either one work ? My understanding is ... you ignore the front. So the difference between the 11 and 34 is 23. So the max capacity needs to be 23 or greater, which most Long & Short cages certainly meet. What is your take on this ?
For more bike repair videos hit the subscribe button 🛑 and click the notification bell ► bit.ly/SubRJTheBikeGuy
I have an old frame here to experiment with. I set it up 1x8 with an 11-32 cassette and rode it for about a month with no problems. Since I'm in flat Florida, today I said, the heck with it and switched it with a 12-21 I had laying around. Same long cage RD. Surprisingly, it works like a charm!
Dude your videos are fantastic! I'm doing up a old 1987 Raleigh Criterium 12 Triathlon by putting modern groupset on it. Now I'm a novice at all this but every time I think of a question you have the answer! From big jobs like fitting a 10 speed cassette to things like this video. It's so helpful and can't thank you enough :)
most people talks too much but say nothing. your are the best. your every sentence has full of information unlike the most other youtubers.
The typical bicycle shop mechanic is only able to assemble and replace parts with identical components. They do not understand properties of materials or design of mechanical assemblies. Walk into your local shop carrying a micrometer and watch their faces change from confidence to confusion or belligerence. The man in these videos is above average and any contradiction to his words by the local guy is a sign to walk away….push that bike to another shop.
Very interesting. Thank you for pointing out how to determine whether a cogset/chainring set will work with a rear derailler before purchasing it. This is a big help for anybody planning to change either their derailler or cogs or chainwheels to a different size.
Phew, this saved me 60 bucks, thank you.
Was about to buy a short cage for my 2x10 with 11/36 T Rear + 24/38 T Front.
Found out I needed a Long gage so I'm glad you had this vid up :D
Everytime I watch your videos I learn something. Thumbs up
YOUR ANSWERS WERE SPOT ON!!!!! It was exactly what i was looking for. It was also very simple and straight to the point.
David, yet again, this video was SUPERB. I did find it extremely useful, in answer to your concerns to the viewer at the end of the video.
Thank you so much Sir!
Who is David?
Sorry "RJ", I made a mistake as I misperceived a big huge "D" symbol framed in red (next to David James) as being the symbol for the OP. I had addressed my initial messages to you "RJ", but on seeing this, I respectfully re-edited my post, with albeit the 'wrong' address.
It was a simple mistake, and no offense was meant. I apologise for this.
Love your videos! I've never had this explained more thoroughly, and FINALLY understand the difference and how to determine which derailleur to use. Thanks, RJ
Great video ! Building a touring bike right now and was asking myself this very question.
Enjoy every single one of your video. Find it Super helpful. Keep up the good work.
I see you have the slx mech , I swapped my old xt mech for one of those and what a big difference it made , the gear changes are so crisp and smooth , very highly recommended :) , another very informative video RJ
I'm using Claris long cage derailleur and its coverage is excellent upto 32t cog. I can upgrade to 2x9 speed later just by changing the shifters and chain~
Wow, explained so well and clearly. Mind is blown. I understand. I'm running a 40 cassette on my road bike with an ss derailleur and a road link :)
Oddly satisfying! Thank you posting.
Thanks RJ. Clear, concise description.
Nice clinic on the subject. Meaty, yet simple and succinct.
Went back to the 11-28. All good for now. Thanks for responding. Ride on.
Great Video. Great topic you discuss and explain clearly. God bless you
Thank you very muchhh, I saved $5 not buying the extra long cage RD! About to purchase a new brifter and bigger gears!!
Wow what a great video very informational!!
Well demonstrated and well explained. I salute you!!
Excellent reference material -as all your videos achieve!
Very good vid this matey. Easy to understand and follow for idiots like me. Keep up the good work. Geoff.
Straight forward and well explained, thanks!
In my country, the country I come from the chain length variation is calculated using a different method yet comes out with the same result. Add the two largest and two smallest possible sets and subtract the smaller number from the larger one. (They call me “Largest Cog”)
I have a double chainring 50/34 and an 8speed cassette 11-28 on a older road bike. I was told that I need to use a long cage. It's a direct mount if that makes any difference? They suggested a Shimano Acera.
Well explained, straight to the point. 👍
Thanks a lot for this video! It's simple and clear.
only one video of urs which explains this all , thanks
Excellent. Thanks for the education!
A long cage, where it is not needed, will cause a lot of chain slap, unless you have a clutch. It can cause you to lose your chain in rough terrain or over common street obstacles like speed bumps and pot holes.
Shorter cage deraileurs do tend to shift faster, quieter and smoother, partly because you get better chain wrap and the guide wheel closer to each cog, but also because there isn't so much to flex (it isxastounding how long a short cage deraileur can stay in adjustment vs a long). These are all niggling things until you apply them to 1x vs triples, with huge range. Also, any e-bike. E-bikes can have problems with power over run with motor inhibitors between shifts, oh and cheaper ones (most) often have sticky freewheels instead of cassettes. Now all that extra chain slop bunches up and causes all sorts of problems.
I have a Shimano Deore LX "9-speed" rear derailer on my bike. It is rated at 45 total capacity, but I am running it at 47 with no problem. 47=(48-24)+(34-11) I don't think it could handle even one more tooth, but at 47, it works fine. This derailer is also rated at 34 for the largest cog, but I know people have run it with 12-36 cassettes. I have also read of people making it work with 10-speed cassettes. Moral: Shimano can be a bit conservative with their ratings. Sometimes you can get away with a little bit more.
+Mark Holm The specs tend to be slightly conservative. But only slightly.
+RJ The Bike Guy Generally, it is not good practices to be shifted into the biggest cog and biggest ring. That is cross-chaining.
When I say it works fine, I mean it can handle both the big-big and the small-small combinations and everything in between. Some people set up a bike with more capacity than the derailer can handle and get away with it by never selecting the big-big or small-small combinations. That is not what I am doing.
Here is a picture with the gears in the small-small position.
picasaweb.google.com/113065978323692444332/BikeBits#5587747131539541730
Here is a picture with the gears in the big-big position.
picasaweb.google.com/113065978323692444332/BikeBits#5587747274927222978
My opinion: The Shimano Deore M591 SGS rear derailer may be the best, general purpose, rear derailer ever made. Rated Capacity = 45, Practical Capacity = 47, Rated Large Cog = 34, Practical Large Cog = 36. Will easily work with 7-9 cogs and can be used with 10, with the right setup. All the parts that should be metal are metal. This derailer is perfect for a wide range of bike trails, touring, commuting,etc. The derailer in my pictures is an extremely similar Deore LX. My wife's bike has the M591. The LX is only cosmetically different from the M591. The other good thing about the M591? It costs less than most of Shimano's decent quality line.
Excelente as always!
if you put a bigger lower jockey wheel is it an alternative to having a longer cage?
Basically if you're not sure, you should ask your local bike shop. I have road bikes that I want to run larger cassettes on because I live in really hilly area and I need to find out what I need to get to do it.
Or do the math. And look up the specs.
Great lesson. Thank you
Thanks for the information. Save's enough money buying what i dont really need
top notch as always RJ. TY :)
Would I be able to use a 26/13 cassette in place of a 32/11 cassette which I already have along with a Shimano Sora derailuer already fitted to my rear wheel
Oh my god your videos are helpful. Double thumbs up!
there's something else to mention: on folding bikes a large cage may contact the tire or even the rim
Beyond the scope of the video, but good info.
I have the SRAM APEX. It is compatible with max. 32T (biggest cog on the cassette) and is a mid cage type of thing. Mounted a 36T and didn`t know what the problem was before finally grasping the nature of the issue. I never knew there was a limit for these things. Guess you live and learn.
Google the specs.
My derailleur has a 28T maximum capacity (largest sprocket: 28T) but I calculated a difference of 34T in my gear range. My bike came like that from the factory. Would it help if I put a derailleur that has a maximum capacity of 30T (largest sprocket: 30T)? And would I be able to ditch the 14x28 tooth for something with a larger gear range like a 14-34T? I never go in, for example, 1-6 or 3-1.
The amount of chain the RD will take up and the largest cog it can handle are two different things. Generally you can go a little larger with the cog size. But don't exceed the capacity.
RJ The Bike Guy is 4T too much?
Great explanation, thank you.
Genious top videos . Very informative .👍👍👍
Thanks for the great video - I know it's old, but this problems is still occurring g today. Now, my drivetrain has changed with the latest upgrade and I need your help understand exactly if a Medium Cage will work.
Old Drivetrain - 3 by 7 : Front 3 rings (42, 36, 29T) Rear: 7 rings (11 to 36T)
New Drivetrain - 1 by 10 : Front 1 ring 32 T, Rear 10 rings (11 to 46T)
Do I need a Long Cage for my New Drivetrain, or a Medium Cage should be enough?
I learned a lot. Great video. God bless
I found this very useful . I have a Fuji Absolute 2.3 but it's set up for a seven speed but it has a Shimano HG 9 speed cassette . I'm just wondering what derailleur to look for n shifters for it as well . I would like to get rid of the front derailleur n go with a 1x drivetrain . Any thoughts or suggestions would be great . New subscriber . Thanx again
good morning, good afternoon: would axle with gears to give the bike all-terrain ...? and how much would come out...?
I'm running a 1x7 drivetrain.weird but how would I figure out a load for a new derailer. which can I use
I have a 1x11 and the chain ring is 32t while the rear derailleur is 11-46. Will a medium shimano m8000 derailleur be ok i already ordered it?
Hi RJ, i have a 2015 GT grade with Shimano Claris. I'm looking to replace the rear derailleur from a short cage to a long cage, this way i can use a 11-34 o 11-36 cassette. Can a use a Shimano mtb rear derailleur with road claris levers? Thank you
I would think so but make sure it is the right number of gears and that the pull of the shifter is the same of the derrailur
Thanks for your videos! I am wondering if this is the reason why my rear derailleur does not shift to the smallest cog when using the biggest chainring? 🤷♂️ I am using an older gen Shimano 600 Groupset (Friction shifters) but testing with a 9 speed Miche Cassettte. (I think it is 13-26 though) and new KMC 9 speed chain. if I shift from the big chainring to the small, the derailleur then will shift to the smallest cog automatically..
What if you only have a single front chain ring. Do you just do the math on the rear cassette to determine total capacity and then which derailleur???
i did a 1x8 conversion should i swap the derailleur to a short cage or stick with a long cage
Go back and watch the video again. And then research the specs of the derailleurs.
Perfect explanation. Thank you
What's the computation for a 1x drivetrain?
Great vid RJ, Thanks
Another amazing content RJ. Your online presence is truly valued. Question though, what's your take on using a rear mech on a drivetrain beyond its spec sheet capacity? Just installed an 11-32 10 speed sprocket using a 5701 SS. I'm 2 teeth over the largest cog and 9 teeth over the capacity. I really do not ride cross-chained, will I have problems in the future?
+Gian Tan The specs are *slightly* conservative. The largest cog spec especially. You can usually go a couple teeth over the largest cog spec with no problems. 9 teeth over capacity? I would be VERY leery of that. If you accidentally shift into too big of a combination you can maybe have some major problems. Maybe destroy the derailleur and who knows what else.
+RJ The Bike Guy Who knows what else may involve snapping my hanger feeding my rear mech into my rear wheel and tip me over face first. Yes I will be very very leery of that. Hehe. Though even running 11-28 before I have never had the habit of using bad combinations.
Why not just install a derailleur with a bigger capacity. Is it a road bike? There are medium cage options for some of those.
+RJ The Bike Guy One last thing RJ if its okay. I fitted my chain to accommodate a big-big combination. Some slack will be expected in small-small but, again, I will never ride in both combinations. Do you think the chain length I used will help minimize risks from the over capacitated rear mech?
+RJ The Bike Guy Medium cages are hard to come by in my area. Pretty much all the shops here have mid cages for 11 speed. I can go with Sora which have higher rated capacity but shifting may be a dud. But I am on an on going hunt for a GS 105 or even a 4700 mid cage.
If I have an 8 speed 11x32 cassette and a single 48t chainring do I need a short medium or long cage derailleur?
Go through the video.
I changed out the wide range freewheel on a 96 Gary Fisher (bought on CL) for a narrow range also changed out the 42T chainring for a 44T. Can and should I change out the long cage for a short cage without getting a new deraillur?
Change the cage without getting a new derailleur? Use a derailleur to fit your specs.
Super useful vid. Really helps. Thanks
Subs to your channel also 👍
Even though you would be adding weight, could you just add more chain length as needed to provide more slack for that derailleur?
No. That's not how it works. ua-cam.com/video/ELsKrgTt0oY/v-deo.html
Chain length should be set so you can shift cleanly onto the big sprocket when it's on the big ring. Then shift to the small ring and sprocket: the derailleur should still be applying tension to the chain. There's more to it if the derailleur has "A" and "B" tension screws.
Good video, I’m doing a project bike and not sure if the derailleur is too big. It has 12 inch wheels (can’t go any bigger) and I don’t want it scraping the floor, how can I measure it? And if it doesn’t fit, what should I do? Are there small enough derailleurs to fit? (I saw one on a 12 inch folding bike but I can’t find that model anywhere. I don’t need much range.
It's your project. You will have to see what works.
Hey RJ.. Could you go over an adapter for the RD hanger that allows the B screw to adjust in far enough that keeps the upper jockey wheel from rubbing the small clog if the B screw is NOT long enough for the adjustment. I've heard of this but not sure what to buy. I have a older Shimano DA onto a new TRek Emonda SL.
Buy a longer screw.
Are you sure you are using the correct derailleur for your freewheel/cassette?The chain length is correct?
Great question.. that answer could be different on who you ask. Im running a Compact 50/34 and 12 -30 Cassette with short cage Shimano Durs ace RD. Shimano says 28T is max but I know from experience you can run a 30T. Climbed 9000 feet over the weekend and a mechanic I ran into said I could buy an adapter or longer B screw to keep it off the upper jockey wheel. The new RD hanger on the Trek doesn't line up very well with the B screw on the older RD. That's when he mention note of the adapter, Thoughts?
I can't see the bike. So I can't give you a solid answer. But I would check everything else before going with a longer b screw.
can you use cheap a 7 speed derailleur , with a 9 or 10 speed cassette the indexing is done by the sifter ,
Maybe.
I don't understand still what the advantage of a short cage derailleur is opposed to a long cage one, besides a slight weight advantage..
That's useful, but how about on a road bike?
ua-cam.com/video/MlAoh36bOOo/v-deo.html
Jochem no more bent derailleur cage that is the most benefit .
he did say long cage generally have a larger capacity
Can you show me how to service headset cartridge bearings which cannot be replaced?
+Shite Muncher You can try lubing the cartridge bearings. Or replace them.
Thank you for your videos sir
Hello im wondering wich derailleur fit my giant escape. any ideas?
I don't make recommendations like that. You have to research what fits your needs and budget.
another good video , thank you lemme ask u, if i changed my front chain ring to be only one instead of 2 it had and didn't touch the rear sprockets \i kept the same 6 it had, would i still apply the same math operation you did or would it change somewhat. thanks again
+Nauj Aral Yes, the math would be the same.
So there is no disadvantage to running a long cage derailleur other than weight? Does it handle torque the same as a short cage?
Derailleurs are not subject to torque, they just guide the chain so no issues.
Im a slacker with megarange.
My derailleaur was damaged and is no longer available.
Tx 31 shimano.tourney.
Any suggestions.
I got a ty 500 and it did not work.
Unless i change crankset and shorten chain.
Not gonna happen.
I would think megarange derailleaurs would work.
A lot of times even though it has more gears...
I set it up for the gears i use.
One up front and a couple in the back and a mega gear.
Thats it.
But most bikes i get have way more crap than i use....and that usually is the intent.
Use defines purpose.
A couple of gears...not 24 speeds.
I just need a couple and an extreme uphill.
Whats with the sprocket madness.
Simple solution is buy a used Megarange derailleur on eBay.
Serious cyclists know where their power range is. They are most efficient pedalling in certain cadence ranges (ie 90-100rpm). More gears allows them to stay in that cadence range at different speed/terrains.
What is your opinion on yellow sun damaged spoke protector? Removed it or replace it?
If it's just yellowed, pull it off and wash it and will probably clean up nicely.
@@RJTheBikeGuy sun damaged plastic are brittle. Crumble to dust. Plastic don't last. I used to used old CD. Cut hole in the middle. But that do not work well, cause it is flat. Need cone shape to match spoke angle.
So I cut sheet mtl to circular shape. Hammer it flat. Watch lots tutorial on sheet metal cold forming. It is possible to DIY spoke protector from sheet metal or metal bottle. Actually pretty easy and fun to make. Can even make it from giant beer can or all the Pepsi can you have in your garage.
But not as good looking as $3 new plastic spike protector or alum mass production spoke protector.
But one of the kind. Signature mount on bike. No one can steal the bike.
Have you make one before?
@@VITAKENNY Then chuck it. Buy a new one, or ride without it.
@@RJTheBikeGuy I did not know what it is for before. Ride without it. And broke the spoķe.
Fly spoke protector from everyday materials. Have u made one ?
@@VITAKENNY ua-cam.com/video/o9oVJUplaQI/v-deo.html
Hey rj I have a mtb with a single 30t in front and 11-34t in the rear. I'm looking to get a short cage to lessen chance of hitting it. Any recommendations? I can't seem to find anything. Using Shimano shifters. 9 speed. Thanks!
+pheoix With a 34, you are probably going to have to go with a long cage mountain bike RD. Most road derailleurs aren't made to go that big.
nice video man learnt alot from this 1 video, i do have a question tho what isa the best value for money mountain bike on the market now hard tail or full sus with a single front drive chain with a rear cassette thanks man
You gotta do your own research as to what makes sense for you.
Can you convert a 14-28 tooth 6 speed freewheel to a 14-34 tooth 6 speed freewheel (if yes, how about a 11-34 tooth 7 speed or a 13-34 tooth 7 speed) without changing the derailleur? Mine is an old model shimano TY18 derailleur. Great video!
Apparently you didn't get much out of this video.
ua-cam.com/video/9R1CVWcgu_M/v-deo.html
Nice to know that, big thumb up for you
Is it possible to determine the capacity of a derailleur without refering to it's instruction sheet (eg, measuring cage length, jockey wheel diameters)?
Not that I am aware of. Maybe if you were a mechanical engineer.
What if I have a single chainring? What calculation should be done?
Same thing except the single chainring is both the big and small chainring.
Hello, very good video!
What are the consequences if a new rear cassette brings the derailleur beyond its total capacity, my chain is sliding along the teeth on the smallest cog when there is pressure applied to the peddles, especially at the beginning of a hill.
I have a dura ace RD7800(29 or less total capacity) and the new cassette is a 7900 11-27 ratio, with a 39-53 front ring?
Thank you in advance
+Martin Burke Then you risk damaging your chain or derailleur if you happen to shift into a combination where you go beyond the capacity.
Wow thank you for the quick response!! Do you think the chain skipping when its on the smallest cog related to that extra tooth of chain length?
the extra tooth of chain length that the derailleur cant take up the slack on?
Thank you again
Not sure. Without seeing it, I can't tell you exactly what is happening.
+RJ The Bike Guy
Thank you for your help, much appreciated!
Don't forget...If you go to a much smaller cassette...say 11/25 from a 11/36 and you have a long cage, It may not shift very well because the derailleur B setting is too far from the 25T cog. That's the problem I have now. So I'm going to use a 11/28 and get a short derailleur.
You have to get derailleurs specially made to handle a 36t cassette. Or a derailleur hanger extender.
When you count the difference in teeth between the smallest and largest cogs and then report that to the chain, should not that number be divided by roughly 2? After all, the chain only goes around half of the chainring/sprocket.
I did it the way it is normally done.
David, could I ask you, in your expert opinion:
I have got a triple 32-42-52 front and a 21/13T rear block. Should I get a short cage or long cage?
My chain wrap value is 28...
But, due to mechanical sympathy on my part, I am *not* going to be using anything more than *4* sprockets on the back with any of the front cranks. By this I mean, the:
32 front paired with 21,19,17,15
42 front paired with 19,17,15,14
52 front paired with 17,15,14,13
So, how does that change things? And as I've heard that a short-cage gives a quicker, more precise shit, would a short cage actually do me?
One last question, if I wanted to put on a 7 or 8 speed block when the 6 speed wears out, I would go *only* as a far as a
23 rear sprocket. If an 8 speed, it would mean 23/12 (maybe).
Would the same short cage fit this too, bearing in mind that I would be leaving out extremes of chain-crossing?
Anyway, the 1st question is obviously far more important for now. Any advice you can give me would be extremely appreciated.
Thanks and God bless :)
I explained exactly how to figure it out in the video. And going from 6 to 7/8 speeds is probably not going to be as easy as just swapping out freewheel/cassette. It gets into hubs widths, shifter compatibility, etc, but that's a whole other issue.
Thank you RJ. As already posted, I did say your video was very useful, and sincerely thanked you for it.
However, the chain wrap capacity value which you outlined in your video appeared to just cover the extremes of combinations e.g. big ring with big sprocket.
As I don't cross-chain like this, I was wondering shouldn't the equation be changed to reflect this?
I only ask as considering that my chain wrap capacity is on a borderline '28' going on a full chain-crossing calculation (i.e. 52-32, and 21-13). And I would rather stay short cage as I've 'heard' that they are a bit more precise and quicker shifting than longer cages.
I have tried many other fora, but can't seem to get an answer on it.
I ask you, as you seem very obliging by your demeanour on screen, knowledgeable, and because you go to the trouble of producing lovely videos for the purpose of educating and helping people with no apparent financial motives.
If my asking still offends you, I understand and apologise sincerely for same.
P.S. Will be using nice, simple friction shifters
You have to take into account ALL the combinations. It's easy to say you never cross-chain, up to the point where you accidentally shift into that combination and destroy your derailleur, take out your rear wheel, crash and die. You can do what you want, but I recommend very strongly to take into account the full range of possible gear combinations as I do in the video.
RJ I don't know why you have to be so confrontational and ungentlemanly. I did apologise and have been nothing but cordial to you since.
You seem to want to help people with your many videos, yet you can't seem to take an innocent mistake and subsequent apology with good grace?
I have a cheap Walmart mountain bike (Hyper Summit) which came with 24-34-42 in front and 28-24-22-20-18-16-14 in back so I would assume that is a medium cage since the range of teeth is medium (18 up front and 14 in rear). The bike came with Shimano derailleurs. I want to go to a Shimano MegaRange gear in the back which replaces the 28 with a 34. I will also try to replace my 24 granny chainring with 20. So I will have added 10 more teeth of possible range to the total system but to help with not exceeding any limits, I can simply never use the largest chainring with the largest cog and never use the smallest chainring with the smallest cog.... Just because I widen the range of teeth doesn't mean I have to use them. I guess the only way to know if my gear mods will work is to try them.
+David James Look up the specs for your derailleur.
+RJ The Bike Guy - I looked in the owners manual and it doesn't mention any specifications about the derailleurs. When I look on the actual rear derailleur, it just has Shimano on it but I don't see any model number or any other markings. Any advice on how I can figure out which model it is? The bike is a new model (introduced within the past 6 months) called Hyper Summit.
Look on the back of the derailleur. It's usually on there somewhere.
RJ The Bike Guy - Yes you are right. It is the Shimano tourney RD-TZ31 rear derailleur. it was very hard to see but when I used a flashlight at the correct angle, I could see it. Thank you! Unfortunately for me the specs online say it maxes out at 28T cog and I want to put a 34T on there. Also my dropouts appear to be 135mm inside diameter between them so should I consider an upgrade to maybe an 8 or 9 speed freewheel if I will be upgrading the RD anyway?
You could maybe put a 30T cog on there. I wouldn't try pushing it to 34 though. 135mm is mountain bike spacing. Frankly I wouldn't spend any money upgrading a Walmart bike.
Very good, easy to understand explanation. If I'm going with a 1x10 drivetrain on a mountainbike (11-32?), I'm assuming a short or medium cage is fine, that the calculation is simply "32 minus 11" or "21". Anything else that I should consider in going 1x__ drivetrain?
Thanks again... so good a video that I didn't mind being flipped off. :-)
You also need a derailleur that can handle the 32 teeth large cog.
Legend - thankyou, very clear.
Rj great vid! Do you have a similar video on front derailleurs??
Front derailleurs are completely different than rear derailleurs. They don't take up chain like RDs.
+RJ The Bike Guy ok thanks. So if i have a triple crank and 8 speed cassette i can use a 3 x 8 front derailleur right?
Probably. FD's also come in road bike or mount bike flavors. There are also different clamp sizes, or even braze on models. And then they are also top pull or bottom pull..
ah ok you should make a video on them I'm sure it would get a lot of views! THANK YOU
Great video thank you
"And now you know...
And knowing is half the battle.."
YO JOE!
Great info.
Hey cool I got the same SLX
Thanks RJ.
Nice video.
Question:
Scenario ... Only one front sprocket (30T) and rear cog set of 11T - 34T, 8 Speed.
How do you make the calculation for Long Cage/Short Cage ? Or will either one work ?
My understanding is ... you ignore the front. So the difference between the 11 and 34 is 23. So the max capacity needs to be 23 or greater, which most Long & Short cages certainly meet.
What is your take on this ?
It's the same calculation. The "difference" in the front is 0.
@@RJTheBikeGuy Ok so in my example it's >= 23 (34-11) ?
@@joeanderson3423 And the derailleur needs to be able to handle a 34t cog! It's all explained in the video.
@@RJTheBikeGuy Yes .... the derailleur is 11-34 Shimano. Thx
thanks. very clearly explained
what kinda free wheel is that
good to know..thank you
thanks great video