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Broken Gear teeth....grrrrr

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So my son's CR85 wouldn't shift right last ride out at Bartow. I took the crankcase apart to see to pieces of metal wedged into the shift forks (I guess that's what there called?). Those pieces of metal (not just shavings but pieces the size of a tic tac) are gear teeth so now the bike needs a bottom end and God knows what's insie the case. grrrr, this was more than I wanted to bite off (I just started doing top-ends a couple of months ago) and the shop needs 1-2 weeks. Now what am I gonna do :thumbsup: without riding for over a week?

BTW, is this normal? His bike isn't even a year old?

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Have you split the cases yet to see what gears are damaged ? Is he shifting with out the clutch ? does he use 1st atall on the track, if he does maybe hes missing his shift up and then slaming into 2nd when he realizes it did not shift.

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Oh man that sucks!!!! I was hoping the issues you guys were having last weekend weren't too bad but it doesn't sound like it.

As for it being normal... to my knowledge, no. I have to agree with bubbyman in that it sounds a tad like abuse of the shifter without the clutch OR proper clutchless shifting techniques.

Hope you can get her up and running soon.

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He's not using the clutch to shift (I don't either, I didn't think anyone does when riding MX?) but he's not in first ever on the track. Even in the slowest turns he's still in 2nd. He's just recently moved up to C class so he's keeping a "decent" pace. But what is "proper clutchless technique"?

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Im not sure on the proper way to shift clutchless. I am not of fan of banging gears under the loads and rpms a motor has when on the track. Use the clutch more it will save you lots of time and money if your having these issues on that new of a bike.

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He's not using the clutch to shift (I don't either, I didn't think anyone does when riding MX?) but he's not in first ever on the track. Even in the slowest turns he's still in 2nd. He's just recently moved up to C class so he's keeping a "decent" pace. But what is "proper clutchless technique"?

The proper technique to "clutchless" upshift is right before you get ready to upshift, very briefly let up off the gas to unload the torque from the gears, then shift, then back on the gas. Its almost one fluid movement.

I would recommend using the clutch during down shifts just cause those are a little harder to synchronize and you aren't loosing anything by using the clutch if you are slowing down.

Banging the gears around without the clutch and under load will eventually cause problems, such as broken teeth or shift forks.

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well as most of you know, we're less than a year into MX, but I've always been taught to keep the gas pinned and shift when upshifting and to just down shift while while braking (never using the clutch in either scenario). But I guess riding like that puts you at risk for tearing up the transmission? But no one we ride with regurlarly has had this problem and they all ride that way too? I would just chalk it up to MX being tough but man with the time and money tied up in this repair I may have to rethink technique vs wear on the bike.

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Myself our my boys ever use the clutch to shift unless our bike is under a heavy load and just won't shift. We have never had any tranny problems. The kids burn out clutchs from slipping them but no tranny problems. One rode a cr80 for 2 years and it made it thru a lot of abuse. Changing tranny fluid regularly is a must. We have replaced shift forks and gears, bearings and shafts to keep anything from coming apart. I really doubt if his riding style caused the problem. Plus it a Honda and they are the best. Just ask Dono.

Dan

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Myself our my boys ever use the clutch to shift unless our bike is under a heavy load and just won't shift. We have never had any tranny problems. The kids burn out clutchs from slipping them but no tranny problems. One rode a cr80 for 2 years and it made it thru a lot of abuse. Changing tranny fluid regularly is a must. We have replaced shift forks and gears, bearings and shafts to keep anything from coming apart. I really doubt if his riding style caused the problem. Plus it a Honda and they are the best. Just ask Dono.

Dan

Did you replace the gears at some maintenance interval though? That's what he's broken.

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I never use the clutch to shift up or down unless your wide open in the deep sand and it just wont shift. good luck with your bottom end

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Yes we have replaced 2nd, 3rd and 2 shift forks thatlooked really bad. This was because the bottom end needed done so of course you get to go thru the trans anyway. I thought I was pretty smart and didn't think the gears looked bad. A close friend who is also a mechanic insisted they should be replaced. Once we got the new parts it was pretty obvious he is the mech. not me.

Dan

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