Motorcycle bottom end rebuild part 2 (of 3) crank & bearings
How-to disassemble and rebuild the crank and transmission on a modern 2-stroke motocross motorcycle or ATV.
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You sure are confident knocking out that main bearing with a ball peen hammer.Why dont you put an extension on that socket so you dont hit the case.
I don’t know about “better”, but If you have lots of money and lack the confidence in doing it yourself, that philosophy is right on.
I have done this before on a 250r with no probs but it sure is better to just take it into an experienced race shop pay the money and be done with it.They got all the right tools too.
I’m actually kind of amazed at how big all this stuff is. I’m used to seeing Maico parts, which are rather on the small side by comparison, I suppose. The compact size of the cases can really be something to behold.
Oh, hello there Toby, what a coincidence.
*Includes both male and female M10×1.25mm and M12×1.25mm adaptors to attach to crank assembly.
The Tusk Crank Puller, what parts come with it to adapt it to the end of the crank? If it can go on my crank nut I guess it could work looks like you bolted something into the crank but if that bolt hole doesnt exist or is worn out you cant do that. Just checking I was thinking of maybe using it on an older bike if it would work before rigging up my own.
can i split a case with out that tusk case spilter?
can i put a motorcycle transmission on a bicycle hehe
You don’t want to pack the bearings with grease inside the motor. They are lubricated buy the premix (main bearings on a 2-stroke) and by the transmission oil in the transmission.
You greased the inside surface of the bearings so you could slide the crank shaft in. I’ve seen some people grease the inside of all the bearings where the balls are. Would you say that this is necessary?
Sorry the water you were throwing on the case to see if it was at boiling temperature totally just went over my head. Haha. I see know what your mean. But thanks for educating me.
Great Vid.
i suppose you could warp it if you applied a lot of heat. You are only heating the case to around 200 degrees Fahrenheit (to water boiling point). This isn’t near hot enough to damage the aluminum or cause it to warp. However, the oven heating method works good too, but be prepared for your wife to be angry at the smell in the kitchen!
Correct me if im wrong. But i heard direct heat like that torch you used can warp your case. And cause premature bearing wear and oil leaks ect. ect. I was told to stick the case half your working on in a oven so it equally heats up your case, so there is less probability of warp-age. I myself use the torch for stubborn bolts and everything else but,im not sure about the cases like this one. Have you ever had any problems with using a torch on a case? I am assuming not since your doing a video.
does ne one no how to remove the clutch off a 110 pit bike?
ive got a 110 pit bike i want to know how to take the clutch off it any ne know?
Some manufacturers sell the case halves together and some sell them individually. Suzuki sells them together and when I had to change the left half for the same reason I had the same question. I measured the new half and comared it to the old — no difference. so I ran only the new left. It worked fine. no problems. Just double check by measuring.
I had a crack in my main case on the clutch side, so i bought a whole new case. Do you think that I can just replace the case half that is cracked, or do you think that the 2 case halfs are milled to be together? Thanks for you help in advance.
oh thanx alot!!! will do
The new top end won’t cause additional stress. if the bottom end is in good shape you will have no problems. Check your main bearings by grabbing the flywheel and try moving it up and down. it should have no up and down movement either.
great vid!! I have a 2003 honda cr125 which I am in the process of getting fixed. Im getting a new barrel due to damage and Im thinking a refreshed bottom end would be needed because of the stress of having a new top end. My con-rod has no up and down movement. Would the stress of the new top end require to refresh the bottom end???
Don’t lose sleep over it. Greasing any seal helps it go in easier and helps it come out easier years down the road. It certainly won’t hurt anything.
But why is this grease used on the outer surface of the seal? I mean, all other seals are installed only using grease on the inner lip but not on the outer surface. Why is this seal different? In my manual, it also says to grease the outer surface but only this left crank seal, I just can’t understand.
I have yet to see one slip out of place.
At 5:50 you grease the outer diameter of the seal. Is it necessary? I think that the seal will not hold tight enough and might slip out of it’s place, doesn’t it?
Hondabond 4 is similar. It should work fine.