Great vid. Back in the day we used lead hammers. More mass, less damage. I have rebuilt H2R Kawasaki and Suzuki triples and they were challenging. Singles were a breeze.
Wait a minute.... Those two halves are ONLY held in by a slip fit!!!??? I did not know this!! How does that not move under engine load!? Wow that's good engineering! You're a master of your craft for sure!!!! I really didn't know this! I'm trying to polish my camshafts and came across this video and its super interesting! Wicked cool thanks for sharing!
Kent Moore had a crank rebuild gig that had spacers so you could press to exact crank web widths! 👍 They were special tools for start up Yamaha dealerships in the 80’s
Can you rebuild 77-78 xr75 , 79 up xr80 ,81 up xr100 cranks? I was told these are not rebuildable due to the tin (sheet metal) side...also i cant find 77-78 xr75 crank pin...Europe says they have them but the pin looks like one for a 73-76.
Shit after you get the press and the tooling to do this your spending way more than just getting a used or even new crank, would be useful for a shop that does cranks a lot though.
I'm currently rebuilding a little suzuki GP125 engine and am at the big end replacement stage. This little crank has 2 holes approximately 25mm diameter in each web half. I assumed that these were for alignment pins, to negate the need for the tureing in a lathe. Am I correct?
What’s the best way to clean up galling on the inner crank web surface? When the crank locked up the bearing race dug into the web and roughed the surface up.
Depends how bad it is. I’ve done it with a die stone many times. I’ve also cut it on the milling machine. If it’s that bad though I usually buy a new crank.
So my question is do you charge a flat rate when rebuilding a crank rather it takes 30 minutes or three hours or does the price change depending on how long it takes?
Hi, great video thanks very much. A few questions... what sort of hand press do you call that? The jig that the crank sits in, can you buy those or did you get it especially made. If so what sort of spec does it need to be? Thanks very much
All the jigs for crank building are custom made. For pressing them apart I have a bigger one & a smaller one for different sized cranks. The V-block setup I had made by a friend. If you want one I can refer you to him. I bet he has the CAD files still. The press is just a cheap 10 ton.
Hi... yeah that would be great. I'm in the UK so its probably to far to ship but if he has the CNC files might be able to build them. Thanks very much its for my kart racing engines
I haven’t come across a crank that is tight enough to crush the stuffers. Building cranks requires attention to detail though, and an understanding of the factors involved.
@@ChuckfromTrueTechalright good to know, so i should be good to make up a tool like that and press it apart? of course keeping an eye on things as well
Hello I have a question about the crank pin. Is it okay if the pin is offet to one direction by a small amount, like 0.1mm, or is that unacceptable? When I pressed my crank back together, the pin is slightly offset and is slightly above the crank web on one side, and slightly under on the other side. Is there any way to fix this without taking the whole crank apart again?
Of course it’s not ideal, but as long as the pin isn’t interfering with the case it should be ok. I would adjust it by putting it back in the disassembly jig, pressing the pin back slightly on the protruding side & then doing the final measurement on the opposite side again.
Plain language , clear and concise . Most excellent.
Great vid. Back in the day we used lead hammers. More mass, less damage. I have rebuilt H2R Kawasaki and Suzuki triples and they were challenging. Singles were a breeze.
Same here. Built lots of twin & triple sled cranks. The odd 4 cyl. Singles are nice.
Wow, what an amazing technician - absolutely spot on. Great show, Chuck! How can you not give a thumbs up...
🙏
Loving your content. I am learning a lot. I have a project bike and I am taking your little tips and tricks.
Very informative Chuck. Thank You for your experience & time & making this video 👍👍
Fantastic! What great videos you’re producing…
Thank you. Gained lots of insights for when I rebuild my yamaha ya6 1964 crankshaft. I hope it does well 😁😁
Good luck! Take your time. Measure everything. Step away if you need to.
Wait a minute.... Those two halves are ONLY held in by a slip fit!!!??? I did not know this!! How does that not move under engine load!? Wow that's good engineering! You're a master of your craft for sure!!!! I really didn't know this! I'm trying to polish my camshafts and came across this video and its super interesting! Wicked cool thanks for sharing!
If I remember correctly it’s the 4th gear on the YFZ450R that’s only held on by interference. That’s some crazy engineering.
Kent Moore had a crank rebuild gig that had spacers so you could press to exact crank web widths! 👍
They were special tools for start up Yamaha dealerships in the 80’s
That would be nice to have. I do all kinds of cranks, so tooling up might be expensive. I often use suspension shims.
Thank's for your channel and your time. Pure Gold👍👍
Great explanation....I'll be doing this shortly to a PW-80 crank
Can you rebuild 77-78 xr75 , 79 up xr80 ,81 up xr100 cranks? I was told these are not rebuildable due to the tin (sheet metal) side...also i cant find 77-78 xr75 crank pin...Europe says they have them but the pin looks like one for a 73-76.
Can’t say I’ve tried. I’ve done CR250s with the tin stuffers.
Beautifully explained :)
great video!
real men build their own cranks😮
Shit after you get the press and the tooling to do this your spending way more than just getting a used or even new crank, would be useful for a shop that does cranks a lot though.
I'm currently rebuilding a little suzuki GP125 engine and am at the big end replacement stage. This little crank has 2 holes approximately 25mm diameter in each web half. I assumed that these were for alignment pins, to negate the need for the tureing in a lathe. Am I correct?
No. Even if you could use then for alignment you’d still have to adjust it after pressing.
What’s the best way to clean up galling on the inner crank web surface? When the crank locked up the bearing race dug into the web and roughed the surface up.
Depends how bad it is. I’ve done it with a die stone many times. I’ve also cut it on the milling machine. If it’s that bad though I usually buy a new crank.
When the swing is out which web do you hit and where
You can hit either web. You just hit it so it moves into alignment. Like closing a rusted scissor.
Do you take any rebuild orders? I have a KTM 300 Crank I would like to rebuild
I’ll do it but if you’re not in Canada the border is gunna kill the economics.
So my question is do you charge a flat rate when rebuilding a crank rather it takes 30 minutes or three hours or does the price change depending on how long it takes?
Flat rate.
Hi, great video thanks very much. A few questions... what sort of hand press do you call that?
The jig that the crank sits in, can you buy those or did you get it especially made. If so what sort of spec does it need to be?
Thanks very much
All the jigs for crank building are custom made. For pressing them apart I have a bigger one & a smaller one for different sized cranks. The V-block setup I had made by a friend. If you want one I can refer you to him. I bet he has the CAD files still.
The press is just a cheap 10 ton.
Hi... yeah that would be great. I'm in the UK so its probably to far to ship but if he has the CNC files might be able to build them. Thanks very much its for my kart racing engines
Hi... I've found a press. I've got a few more jig questions. Are your resssed jigs 22mm mild steel plate?
The pair of raised jigs look like 25mm?
I have a older ktm 300 crank with larger plastic inserts on it, would using a special tool like that to press it apart crush these plastic inserts?
I haven’t come across a crank that is tight enough to crush the stuffers. Building cranks requires attention to detail though, and an understanding of the factors involved.
@@ChuckfromTrueTechalright good to know, so i should be good to make up a tool like that and press it apart? of course keeping an eye on things as well
Are you sure it's not just the Web flexing and pinching the pin... resulting in difficult removal?
Did you make that set of v blocks? Looking to get a set similar.
Had them built at a machine shop.
Do you do crank work or is there someone you would recommend sending one to? Thanks.
I do but if you have to ship it, it’s usually faster & the same price to get a crank assembly.
@@ChuckfromTrueTech not sure this crank assy can be purchased unfortunately.
Hello I have a question about the crank pin. Is it okay if the pin is offet to one direction by a small amount, like 0.1mm, or is that unacceptable? When I pressed my crank back together, the pin is slightly offset and is slightly above the crank web on one side, and slightly under on the other side. Is there any way to fix this without taking the whole crank apart again?
Of course it’s not ideal, but as long as the pin isn’t interfering with the case it should be ok. I would adjust it by putting it back in the disassembly jig, pressing the pin back slightly on the protruding side & then doing the final measurement on the opposite side again.
@@ChuckfromTrueTech Ill do that today, thanks
What kind/size press are you using?
Chinese 10 ton. It’s enough for any crank I’ve come across and I can feel what it’s doing.
nice!
Do you really need to true it or whatever
The clearance in the crank bearings is measured in hundredths of a mm. A wobbling crank easily exceeds that.
Can I send you a 2 stroke crank to work on?
You could but you could probably buy a new one for the same price by the time you factor in shipping.
Whats is the name of the tool please
Which tool?