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01 yz250 crank bearings

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I'm a mechanic for a living but not a dirtbike mechanic, stuff goes hand and hand a little. I've done all work possible on a dirtbike over the years but never a crank. What should I look for/not do or watch out for! Is there a normal catch spot when splitting or when it opens will washers/gears fall out? Thanks

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nothing will fall out

use a proper case splitter and double check all the bolts are removed from around the case

just take a little extra time to split cases 

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Let's not mention this! I knew it 2 hrs after buying but it's cleaned up now and ready to weld. It did last though, it's been years

IMG_20170717_151300470.jpg

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1 minute ago, Smoking 2's said:

Let's not mention this! I knew it 2 hrs after buying but it's cleaned up now and ready to weld. It did last though, it's been years

IMG_20170717_151300470.jpg

 

Damn that is ugly. Looks like you could probably pull all the JB weld off and fix it right since you are splitting case and the JB goes right across the midle cases. 

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I knew one day this would happen, and here it is! My head's not down, it's more of a happy it's over kind of thing. I couldn't find my flywheel puller so things are on hold till Wednesday, then it's on! Thinking back that was a waste of alot of jb weld! Lol

IMG_20170717_160502652.jpg

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There is a great fix for that once you crack the case. You can weld and retap it. I'm looking for the thread, and maybe some else will find it sooner.

Edited by P84ONE

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Thanks fellow riders! I'm open to anything. I was a welder prior to turning to wrenches but I forget alot! Please inform me, magnesium is tougher to weld from what I remember but can't remember the protocol to it.

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On 5/18/2015 at 4:26 PM, Throttle5 said:

Yeah that's a chunk of epoxy LOL, po was a real winner. :bonk:   Found a nice round piece of aluminum to repair with, off to see the welder toorrow !

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5 minutes ago, Smoking 2's said:

Thanks fellow riders! I'm open to anything. I was a welder prior to turning to wrenches but I forget alot! Please inform me, magnesium is tougher to weld from what I remember but can't remember the protocol to it.

There you have it.

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See page 53 of What did you do to your YZ today?

Click the arrow thing on the top left of Throttle5 said.

Edited by P84ONE

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I had a stripped out drain plug repaired once. The shop bored out the case and welded in a 3/4" diameter slug, that was then tapped to the original size. looked better than factory.

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6 minutes ago, Smoking 2's said:

After thought, was that jb weld running down the cases

Yep, he had the same problem of JB weld for quick fix. I believe he had the best fix of them all. I even told throttle if I ever need a fix like that I am sending him the case. :thumbsup:

Just now, Ron W said:

I had a stripped out drain plug repaired once. The shop bored out the case and welded in a 3/4" diameter slug, that was then tapped to the original size. looked better than factory.

Got any photos of that Ron?

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I will just drill/tap a size over if needed, plenty of meat on the bone. Jb will not be on my bike anymore! Come Wednesday after 3pm east please be on your toes, I hope I have no questions but might!

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11 minutes ago, Smoking 2's said:

I will just drill/tap a size over if needed, plenty of meat on the bone. Jb will not be on my bike anymore! Come Wednesday after 3pm east please be on your toes, I hope I have no questions but might!

Your problem will be clearance Clarence. The hole goes strait into the shift drum and if the bolt makes contact, you will not be shifting gears. This was a problem with "some" magnetic drain bolts. I bought a bike for 800 because it didn't shift passed 3rd. After splitting the case and inspecting everything, that was the problem but not without consequence. It had bent shift forks and shift fork guide from the force of "trying" to get it to shift into 4th and 5th. So, keep that in the back of your mind when tapping etc. 

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Will do, if it's past the case by measuring I will cut it down. I replace the piston every year needed or not, however the magnet could be great but I'm not a pull cases apart for the check kind of guy, we're within 20 mile of the truck and I carry the 4 wheeler for a tow, it sucks but throw the front wheel up, strap down and off I go! I really do appreciate all ideals.

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Another question before tomorrow, the book shows separation of cases are done on the right side, but seems like every video I've seen was done on the left side. Does it matter?

Also the tool sold for separating has 3 pull points but the book shows just a standard T-bar type puller.

Here's a pic of what the book shows to do using those bolt holes in the pic.

IMG_20170718_101338076_HDR.jpg

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Either side for separation is fine. I prefer the three point, but you can make do with that slowly and use rubber dead blow hammer or mallet to help it along.

Good luck, take your time, youll get it. 

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