8 yrs ive watched freewheel and cassette definitely grtting phils oil u are a awesome teacher. And your knowledge is awesome thank u for the videos u do.
Garik Oganesyan, I used mineral spirits in a similar video when fixing a sticky freehub. The freehub was smaller and would fit into a jar. I would have needed a small tub for the freewheel. So WD-40 seemed a better choice.
As a follow up; I picked up some machine oil today from Wal-Mart that can be used for bikes. It is not Phil Tenacious as they did not carry it. However I noticed a HUGE improvement! I owned a Fuji Allegro Valite that would glide when I rode it. Tonight I felt that same glide after using the proper oil on my mountain bike freewheel. I wasn't sure if these could be serviced and it was difficult finding good videos on it. So thanks again RJ! Much appreciated! You definitely earned a sub! 👍 👍 👍
@@RJTheBikeGuy Thank you! I really like how you have particular attention to details. I have seen many mechanics make erroneous diagnostics by not putting parts through their paces. I really look forward to looking through your videos to see what else you got going on. Mechanics both bike or car, it pays dividends to learn from others mistakes and trials and errors. You seem very knowledgeable about these things. Are you an engineer or mechanic by trade? I am new to the channel so if it has been states in a video before this I wouldn't know.
Badly sticking freewheel on an old mountain bike; I cheated and tried the easiest fix first - just sprayed WD40 into it *without removing the wheel first* . It worked.
Hey rj my freewheel got a piece of the rubber inner tube stuck in there. What's your recommendation for that? Please answer as I need to fix it. Also my bike has a motor so it must do 30 mph without eating itself alive
Without seeing it I can't say exactly what you need to do. Just do whatever it is that solves the problem. Remove the freewheel from the hub. It shouldn't be that hard to remove whatever debris is there.
Maybe... it seems to work fine with mine so I think it's fine just be careful with the oil going into your disc rotor / rim it'll cause it to be loud as heck or weaken the braking power
Fantastic video and a real service for the vintage cycling community! A couple of additional suggestions: 1. Isopropyl alcohol 91% is a good cleaner and solvent of old grease. It also drains more easily than WD40. Even better is spray brake cleaner. 2. When reinstalling the freewheel, grease the hub threads so you can get it off in the future. 3. If you don't have a remover tool but it needs oil, place the bike on its left (non-derailleur) side and dribble Phil Wood Oil into the tiny gap between the outer shell and the body on the right side. It takes forever but you can get oil into the body that way.
Nice vid!! In automotives, when we use "gear oil" (thick, sticky oil for gears), we heat the container in a bucket or sink of hot water. Even the sun and a warm place against a reflective surface works great. Then the lube will be runnier for pouring, installation, flowing thru a tube etc. Stay gold.
It's a quick fix but since you're removing the freewheel it's a good idea to remove the locknut and inspect the bearings, cups and palls. Stickiness is often an indication that the palls are gummed up from years of dirt and old grease. I've seen everything from caked up lithium grease to cracked or egged out bearings. So much depends on the age and use. If it's been years since it was last serviced and you're replacing the chain and derailleur pulleys it's best to do a complete overhaul and/or replacement if needed.
Great video! I was wondering why my road bike, while coasting, occasionally felt like something was stuck in the rear brake, and the top part of the chain was dropped down. Problem solved!
Washing freewheel in diesel of gas fuel is much more efficient on old funky parts, not to mention faster. Just do it outside so fumes don't get to your head. I lubricated my freewheel with old stock 10w30. It works great and it was free. Simple solutions work best.
It is so great to get info and knowledge about freewheels, still so many bikes around with 7 speed freewheels!. If you go to a modern shop today to consult something about a freewheel, often they will hardly know what to advice. Maybe the mechanic yes (but this one usually they keep him/her in the basement with no contact with customers), but definitely not the normal attendants, unless it is a very good shop.
Hold the wheel vertically with the freewheel away from you and the wrench horizontal and push down; you can't exert enough force pulling toward you or sideways as in the video, and it's not general practice; if it's stuck put the wheel with remover in a vice and rotate the wheel, you can generate sufficient torque that way.
What if some click sounds coming from free wheel or chain!, It can't be bottom bracket cause i replaced bearings and tighten everything at front side. Nd also my freewheel having same problems like this freewheel, it sometimes rotates the tyre backwards
I have a trek 820 free mtn bike. Can I swap the 3 chain ring set to a two ring set. Looking to turn into a hybrid/ road bike to loose weight for excel use to hop back on my early carbon fiber specialized road bike again
here we go. thats the issue i have. the thing is my hub and freewheel are suposed to be new as i got as replacement for the failed one. could this be also an issue just because its new, or they prob screwed up during assembly?the thing is to take the freehub a pat its so far impossible as i have to unscrew a 15mm boltt from the non DS and its tight as hell...so im thinking of even chaning the wheel for a easy to maintain one...cheers
Automotive brake cleaner works even better than WD-40. The old grease and dirt will just pour out the front of the freewheel body as you spray the brake cleaner in from the back. I use CRC brand which you can get in any auto parts store.
Don't use a breaker bar, the safest method is to put the tool in a vice and use the leverage of the wheel (and your entire upper-body) to undo it. I'd flush it out with disc brake cleaner, it's my go-to solvent for any dirty job.
Man you have no idea how helpful this video was to me. I didn't know you could get lube into the sprocket like that. Mind you I used a mix of normal bike grease and WD40 to get the grease in. I had regreased the front and rear hub bearing and even my top bracket bearings. The "grease" they put in brand new bikes is an absolute travesty. It is honestly a safety hazard in many ways. I will apply the appropriate bearing lube/oil before too long. Huge thanks! This was a huge help!!!
@@RJTheBikeGuy Thank you, I will look into that immediately. I don't usually ever use WD40 but I am in a pinch at the moment. I also subbed to your channel. The only thing I need to do now is re-lace my rear rim after an accident left me with 4 broken spokes. XD Again, great info! Thanks! 👍 👍 👍
My touring trek bike was on the corner of my bedroom for 10 years withtout being used, now I tried to put on a trainer to do indoor exercise. After I set up on the trainer, the rear wheel does not spin when when I hit the pedal, then I removed the bike from the trainer, and walked the bike on the floor, and the wheels move, but when I use the pedal with my hands, the rear wheel moves slow, what could be? Before I did all this, I used dental brush to remove dust on and around this area, also I believe some build up of grease coming from kitchen affected the bike during 10 years. Does dust, dirty affects the wheel? What should I do, do I need to take to the store or I can use oil, which oil? how I can clean the whole thing. I am illiterate with bike, I don't even know how to change tire, I don't know why the air pin went inside the flat tire on my another bicycle. Note: I am female, I learned riding bike by myself when I was 42 years old, and enjoyed the rides, but then I had a very stress circumstance in my life during this 10 years, and I stopped the riding, and I want to resume the riding. What happened if I try to ride the bicycle,will the wheel spin normally, or the bike will fall with me?
So, I'm gonna have to rip it off and flood it out. Can I use JB blaster and spray at it without having to take it off? I don't have any specialty tools.
I love your videos dude you’re very educational very insightful. Was just wondering if you had any experience with magnesium alloy wheels, or if you posted any videos on them.
Hello. I use the same way of maintenance of the freewheel. It is worth to heat the temperature of the freewheel, then the oil penetrates inside better. I use the lubricant "IPONE SanadChain", after evaporation it is resistant to water, and quietens the work of freewheel. I'm using a google translator, I'm sorry for mistakes.
Hey RJ, almost every time I change my tire, I ether struggle to remove or put it back on and after hard effort to find out the tube is accidently puncher and leak even I using nylon tire remover levers and have to do it all over again often, can you please make video of best way to change tire.
Hi mate not sure if my problem is the same but the casette (looks like the metal gears in this video) stick to the wheel while im free riding so the chain then slips. Need to ride it today so am a little bummed.
Hi, I have a freewheel UG doing strength given by old age and moisture that cycling has taken remaining still in a very damp garage. You advise me to completely disassemble the freewheel to clean and lubricate it with a Teflon grease or steps in this your video? I would use for the city. If I had to take it apart completely should I buy well as tools. Thank you very much for your videos.
+capitanon I am not sure what you are asking. You mention UG, Uniglide? That is a freehub/cassette and not a freewheel. Taking them apart is last resort. Generally these are considered disposable, they wear out, you replace them. But you can clean/lube them like in the video.
I would clean with something that doesn't leave residue that might interfere with the properties of the Tenacious Oil, something like isopropyl alcohol or automotive brake cleaner.
@@RJTheBikeGuy "Not enough WD-40 residue is left to matter." That may be true, but e.g., isopropyl alcohol leaves no residue at all, so there isn't even a chance of it interfering with the oil. Plus, it's cheaper than WD-40. If you're not concerned about residue, just use gasoline. You can buy a whole gallon of it for a couple of dollars. That's cheap enough that you can submerge the freewheel in it and let it soak for a while, to make sure it's really clean.
Is it a sticky freewheel if the sprockets rotate with the wheel when I stop pedaling, then I have to pedal about 1/2 revolution with zero resistance until it re-engages to where I can transmit torque?
It's good to put some lubricant on the freewheel threads so You can get it better off of the hub from the hub. Otherwise a great informative video! Keep up the good job!
Your bike doesn't seems like a freewheel you don't need a chain whip for a freewheel to be removed your bike seems like it has a cassette you will need a chainwhip for that
For more bike repair videos hit the subscribe button 🛑 and click the notification bell ► bit.ly/SubRJTheBikeGuy
6 years have passed and you still save beginners like me thank you!!
8 yrs ive watched freewheel and cassette definitely grtting phils oil u are a awesome teacher. And your knowledge is awesome thank u for the videos u do.
)
7 Years have passed but JEEZ you're still helping us alot!
5 years passed but this video is still saving days for people like today for me :) thanks
Lol! Great instructive tutorial on da freewheel stickies!!
Just had this problem on a Shimano 12 speed Di2. I took it all apart, cleaned it up, and it’s running great. Thanks.
Garik Oganesyan, I used mineral spirits in a similar video when fixing a sticky freehub. The freehub was smaller and would fit into a jar. I would have needed a small tub for the freewheel. So WD-40 seemed a better choice.
As a follow up; I picked up some machine oil today from Wal-Mart that can be used for bikes. It is not Phil Tenacious as they did not carry it. However I noticed a HUGE improvement! I owned a Fuji Allegro Valite that would glide when I rode it. Tonight I felt that same glide after using the proper oil on my mountain bike freewheel. I wasn't sure if these could be serviced and it was difficult finding good videos on it. So thanks again RJ! Much appreciated! You definitely earned a sub! 👍 👍 👍
Something else that might work well is chainsaw bar oil.
@@RJTheBikeGuy Thank you! I really like how you have particular attention to details. I have seen many mechanics make erroneous diagnostics by not putting parts through their paces. I really look forward to looking through your videos to see what else you got going on. Mechanics both bike or car, it pays dividends to learn from others mistakes and trials and errors. You seem very knowledgeable about these things. Are you an engineer or mechanic by trade? I am new to the channel so if it has been states in a video before this I wouldn't know.
ua-cam.com/video/vr2KNjxbhjg/v-deo.html
Thanks a lot! You're a life saver. I was having to walk everywhere for a week.
Great video very helpful i have the same issue and needed help and advice your video is bang on the money thank you from ireland.
Thanks. Had the trouble and followed your instructions. Fixed - freewheels spins nicely.
Thanks RJ, followed your video and fixed my sticky freewheel. Just what I needed.
Much appreciated and exactly what I needed.
Thanks working on one now, this helped a lot.
Best video on UA-cam
Always so helpful thank you.
Saw a bike tech put the removal tool in a vice and turn the wheel instead - freewheel released simply and effortlessly.
Great video
Is sticky freewheel affect your ride?
Badly sticking freewheel on an old mountain bike; I cheated and tried the easiest fix first - just sprayed WD40 into it *without removing the wheel first* . It worked.
This just saved my old crappy freewheel. What happened to the Nishiki?
I gotta try this with an old bike I found thrown away due to a seized freewheel. I'm sure that's nothing that a little lubrication can't fix :)
Good Stuff, just bought a 2nd hand bike and I like my bikes to perform best as they can...
Hey rj my freewheel got a piece of the rubber inner tube stuck in there. What's your recommendation for that? Please answer as I need to fix it. Also my bike has a motor so it must do 30 mph without eating itself alive
In between the freewheel and axle
Without seeing it I can't say exactly what you need to do. Just do whatever it is that solves the problem. Remove the freewheel from the hub. It shouldn't be that hard to remove whatever debris is there.
+RJ The Bike Guy I got a picture. I'll tag ya on Google
RJ The Bike Guy I posted the pic
Tagging don't work but here is the link: plus.google.com/+funnypranker34/posts/NQSd35fAQYs
How many teeth on biggest front chainring ?
Can you do this without the special tool? And, can you lube it up with a chain oil/lube? Thanks
Maybe... it seems to work fine with mine so I think it's fine just be careful with the oil going into your disc rotor / rim it'll cause it to be loud as heck or weaken the braking power
great video! do you have an alternative to Phils tenacious oil for re-lubing the freewheel?
Not really. This is what I use. This is what most shops use.
Fair enough...wonder if its the same over here in the UK. There is 3in1 oil but doesn't have the same consistency (thinner)
I have read chainsaw bar oil might work.
Jack Greenaway , yes ,,, definitely ,,, Valvoline , gear - oil
Just take a heat gun to it. Then add some oil. No removal of anything. No tools needed.
is marvel mystery oil good for free wheel's
No idea.
what's a good lube beside's phil's tenious oil
I use Phil Tenacious oil. I am sure other stuff will work, but you on your own with that.
ok guess i'll get some phil's tenious oil
My Freewheel is Completely Stuck.....it won't move a single millimeter!
I guess I'm going to have to let it Soak in a bucket of WD40?
Fantastic video and a real service for the vintage cycling community! A couple of additional suggestions:
1. Isopropyl alcohol 91% is a good cleaner and solvent of old grease. It also drains more easily than WD40. Even better is spray brake cleaner.
2. When reinstalling the freewheel, grease the hub threads so you can get it off in the future.
3. If you don't have a remover tool but it needs oil, place the bike on its left (non-derailleur) side and dribble Phil Wood Oil into the tiny gap between the outer shell and the body on the right side. It takes forever but you can get oil into the body that way.
Nice vid!! In automotives, when we use "gear oil" (thick, sticky oil for gears), we heat the container in a bucket or sink of hot water. Even the sun and a warm place against a reflective surface works great.
Then the lube will be runnier for pouring, installation, flowing thru a tube etc.
Stay gold.
Gear oil smells awful though! :-(
It's a quick fix but since you're removing the freewheel it's a good idea to remove the locknut and inspect the bearings, cups and palls. Stickiness is often an indication that the palls are gummed up from years of dirt and old grease. I've seen everything from caked up lithium grease to cracked or egged out bearings. So much depends on the age and use. If it's been years since it was last serviced and you're replacing the chain and derailleur pulleys it's best to do a complete overhaul and/or replacement if needed.
The point of this is to clear out the old grease. You don't always need to take them apart, if ever.
Great video! I was wondering why my road bike, while coasting, occasionally felt like something was stuck in the rear brake, and the top part of the chain was dropped down. Problem solved!
IT TOOK ME SOOOOO LONG TO FIND😂😂😂 I couldn’t make the buzz at a bike shop for a mechanic so they didn’t know what to do and neither did I
My new bicycle too had this problem and after watching your video, I am confirmed that problem is caused by the freewheel. Thanks!
If I pedal backwards my chain just goes limp.
Washing freewheel in diesel of gas fuel is much more efficient on old funky parts, not to mention faster. Just do it outside so fumes don't get to your head. I lubricated my freewheel with old stock 10w30. It works great and it was free. Simple solutions work best.
It is so great to get info and knowledge about freewheels, still so many bikes around with 7 speed freewheels!.
If you go to a modern shop today to consult something about a freewheel, often they will hardly know what to advice. Maybe the mechanic yes (but this one usually they keep him/her in the basement with no contact with customers), but definitely not the normal attendants, unless it is a very good shop.
Hold the wheel vertically with the freewheel away from you and the wrench horizontal and push down; you can't exert enough force pulling toward you or sideways as in the video, and it's not general practice; if it's stuck put the wheel with remover in a vice and rotate the wheel, you can generate sufficient torque that way.
What if some click sounds coming from free wheel or chain!, It can't be bottom bracket cause i replaced bearings and tighten everything at front side. Nd also my freewheel having same problems like this freewheel, it sometimes rotates the tyre backwards
I have a trek 820 free mtn bike. Can I swap the 3 chain ring set to a two ring set. Looking to turn into a hybrid/ road bike to loose weight for excel use to hop back on my early carbon fiber specialized road bike again
here we go. thats the issue i have. the thing is my hub and freewheel are suposed to be new as i got as replacement for the failed one. could this be also an issue just because its new, or they prob screwed up during assembly?the thing is to take the freehub a pat its so far impossible as i have to unscrew a 15mm boltt from the non DS and its tight as hell...so im thinking of even chaning the wheel for a easy to maintain one...cheers
Automotive brake cleaner works even better than WD-40. The old grease and dirt will just pour out the front of the freewheel body as you spray the brake cleaner in from the back.
I use CRC brand which you can get in any auto parts store.
My nick stopped back pedaling and the pedals stopped working sometimes they continue going after I take my foot off or the get stuck and don't move
Why would you do this vs opening the freewheel? I am seeing different opinions about opening a freewheel and would like to know why to and why not to.
oh thanks sir i have this prublum i chang wheel i west alot mony
I use automobile gear oil for free wheels and free hubs. Similar viscosity to Phil. Excellent lubricant. A lot cheaper.
Mark Holm , Valvoline ?
Don't use a breaker bar, the safest method is to put the tool in a vice and use the leverage of the wheel (and your entire upper-body) to undo it. I'd flush it out with disc brake cleaner, it's my go-to solvent for any dirty job.
You forgot to smear grease or anti-seize on the fw threads before screwing it back in the hub!
safe to say, if your bikes wheel doesnt spin easily then bike riding is alot more harder?
Thank you sir, my 13 year old neglected bike lives on!
If the axel is hold the wheel can not spin freely. what would be the reason?
That was so satisfying seeing the freewheel turning from that tight spot
Do i have a freewheel? I have a cassette and a hub. Whats a freewheel?
Aren’t there tiny bearing balls inside the cassette?
Man you have no idea how helpful this video was to me. I didn't know you could get lube into the sprocket like that. Mind you I used a mix of normal bike grease and WD40 to get the grease in. I had regreased the front and rear hub bearing and even my top bracket bearings. The "grease" they put in brand new bikes is an absolute travesty. It is honestly a safety hazard in many ways. I will apply the appropriate bearing lube/oil before too long. Huge thanks! This was a huge help!!!
Cool, but I think Phil Tenacious would work better.
@@RJTheBikeGuy Thank you, I will look into that immediately. I don't usually ever use WD40 but I am in a pinch at the moment. I also subbed to your channel. The only thing I need to do now is re-lace my rear rim after an accident left me with 4 broken spokes. XD Again, great info! Thanks! 👍 👍 👍
Mine won't spin with the pedal ..it's so hard
Thank you very much for the great video with explanation, thanks to the master who was explaining on the video
I tried NOT to get caight riding in the rain, I swear it!!🙈 Thanks again!A+!👌😮
that cassette is attached to the freewheel?
thanks
very useful hack bike hack
My touring trek bike was on the corner of my bedroom for 10 years withtout being used, now I tried to put on a trainer to do indoor exercise. After I set up on the trainer, the rear wheel does not spin when when I hit the pedal, then I removed the bike from the trainer, and walked the bike on the floor, and the wheels move, but when I use the pedal with my hands, the rear wheel moves slow, what could be? Before I did all this, I used dental brush to remove dust on and around this area, also I believe some build up of grease coming from kitchen affected the bike during 10 years. Does dust, dirty affects the wheel? What should I do, do I need to take to the store or I can use oil, which oil? how I can clean the whole thing. I am illiterate with bike, I don't even know how to change tire, I don't know why the air pin went inside the flat tire on my another bicycle. Note: I am female, I learned riding bike by myself when I was 42 years old, and enjoyed the rides, but then I had a very stress circumstance in my life during this 10 years, and I stopped the riding, and I want to resume the riding. What happened if I try to ride the bicycle,will the wheel spin normally, or the bike will fall with me?
Bike shop sold me a new wheel……ripped off! Thanks mate I think I can fix the real problem now! Wish I still had my old wheel!
That oil has a "stringy" appearance like bar and chain oil for chainsaw. Could bar and chain be used here?
Maybe.
What did you spray in free wheel
So, I'm gonna have to rip it off and flood it out. Can I use JB blaster and spray at it without having to take it off? I don't have any specialty tools.
I love your videos dude you’re very educational very insightful. Was just wondering if you had any experience with magnesium alloy wheels, or if you posted any videos on them.
Hello.
I use the same way of maintenance of the freewheel.
It is worth to heat the temperature of the freewheel, then the oil penetrates inside better.
I use the lubricant "IPONE SanadChain", after evaporation it is resistant to water, and quietens the work of freewheel.
I'm using a google translator, I'm sorry for mistakes.
Excellent.
Thanks.
Thanks mate
you did a great job man! im actually learning every videos you made thanks for these i got a lot of tricks from you!
He ia the best
Hey RJ, almost every time I change my tire, I ether struggle to remove or put it back on and after hard effort to find out the tube is accidently puncher and leak even I using nylon tire remover levers and have to do it all over again often, can you please make video of best way to change tire.
Nice video! I have a few kids bikes that seem to have a lot of dirt inside of them. Are they made the same as this?
A real nice and clear explanation and fix of a possible or just maintenance of your freewheel. Great job!
Hi mate not sure if my problem is the same but the casette (looks like the metal gears in this video) stick to the wheel while im free riding so the chain then slips. Need to ride it today so am a little bummed.
Great video - exactly my problem - thanks
That was so satisfying seeing the freewheel turning from that tight spot to full on beast 3:56
3:56 woohooooo!!!
There's a grinding/scraping sound in my freewheel could it be that the bearings need some oil ?
Try to clean and lube them like in this video. If they still grind then maybe replace or overhaul.
RJ The Bike Guy bike is a week old ,doubt it would need replacing already
Take it back to the shop and have them fix it.
Have almost same problem. But in my case, it was bent axle
To helpful after 6 years, thanks Sr.
This man is a genius with bikes. Thank you very much
nice video, thnx for that, will make my bike maintenance much more easier!
Hi, I have a freewheel UG doing strength given by old age and moisture that cycling has taken remaining still in a very damp garage. You advise me to completely disassemble the freewheel to clean and lubricate it with a Teflon grease or steps in this your video? I would use for the city. If I had to take it apart completely should I buy well as tools. Thank you very much for your videos.
+capitanon I am not sure what you are asking. You mention UG, Uniglide? That is a freehub/cassette and not a freewheel. Taking them apart is last resort. Generally these are considered disposable, they wear out, you replace them. But you can clean/lube them like in the video.
Turns out I forgot to remove the old gaskget to make room for the new one. :-)
Why did you not disassemble the freewheel? like in the video "Bicycle Freewheel Disassembly/Assembly"
In most cases, it doesn't need to be disassembled. Actually, I rarely do that.
Thanks for posting your videos. They're very helpful. Keep 'em coming
I would clean with something that doesn't leave residue that might interfere with the properties of the Tenacious Oil, something like isopropyl alcohol or automotive brake cleaner.
Do what you want, but this works fine. Not enough WD-40 residue is left to matter.
@@RJTheBikeGuy "Not enough WD-40 residue is left to matter."
That may be true, but e.g., isopropyl alcohol leaves no residue at all, so there isn't even a chance of it interfering with the oil. Plus, it's cheaper than WD-40. If you're not concerned about residue, just use gasoline. You can buy a whole gallon of it for a couple of dollars. That's cheap enough that you can submerge the freewheel in it and let it soak for a while, to make sure it's really clean.
Any ideas on how to remove stubborn freewheel? I have a tool,but the leverage is not enough
what if it does this with a cassette/freehub?
Is it a sticky freewheel if the sprockets rotate with the wheel when I stop pedaling, then I have to pedal about 1/2 revolution with zero resistance until it re-engages to where I can transmit torque?
Sounds like it could be.
@@RJTheBikeGuy thank you!
It's good to put some lubricant on the freewheel threads so You can get it better off of the hub from the hub. Otherwise a great informative video! Keep up the good job!
I use anti-seize copper grease..
Cheers man, super helpful
Thanks!
Thanks a mil man!
how did u loosen the freewheel without it spinning? usually ppl use a chain whip
Your bike doesn't seems like a freewheel you don't need a chain whip for a freewheel to be removed
your bike seems like it has a cassette you will need a chainwhip for that
Can I do this without removing the freewheel?
I don't have the tool to remove the freewheel.
Probably, but it will be messy as hell.
Muy buenos vídeos
Very good vídeo