07 RMZ 250 Worn gears. PICS!

So, I'm in the process of doing a complete top and bottom end rebuild for a friend of mine, and while we are waiting on head work and a valve job, I have been looking at the transmisison. I have been looking at many threads of people complaining about the weak transmission of the 07-08 rmz250's, so I figure it should be addressed before we put it back together. There is clearly some wear on the gears where the dogs engage. From the pics I have shown, does this look like they need to be replaced? Keep in mind these gears are approx $75 each. To the people who are also having shifting problems and false neutrals, did your gears look like this? I also found a small spot where there is a "dent" on the shift drum. I know if it was a pro bike/rider there would be no question to replace, but this is for a "d"-ish level rider who will ride more woods than moto. WWYD?

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ive had similar wear in the transmission of a few of my last bikes. unfortunately, the suzukis are more prone to hittin false neutral while shifting, which can cause premature wear of the shift dogs... unfortunately, the drum, gears and thrust washers on the secondary (driven) shaft is what i would personally replace as a minimum. i cannot recommend anything less of this...

they def have some wear but dont look tooooo bad, you can def get some more hours out of em, id personally run em as is unless its a race bike or he rides super hard.

Thanks for the input guys. I really do appreciate it. If I do as funkinalive suggests, the gears alone are going to be about $420. I don't think its in the budget. I just wonder how bad it will be. Based upon the wear you see, do you think it will hit false neutral while shifting, or jump out of gear...or both? I feel bad for this kid as he has already bought a new crank, bearings, jug, piston, valves, head work, etc.

i guess the point im trying to get across is if he's already put a crank,bearings, jug, and piston in it, then the kid will be verry dissappointed to find out later that the tranny is garbage. you only showed a few gears. are they all damaged like that? or just the ones in the pics? replace just the ones in the pics if they are the worst and at least consider getting the drum maybe even second hand... it would be an even greater shame if he's invested so much so far, only to have it let him down sooner rather than later. as is, and under moderate riding/racing conditions i would say that there is a strong chance that it would drop out of gear.

EDIT: actually looking again at your drum it doesnt seem TOO bad. other than that dent (who knows what that was caused by) inspect the peaks and valleys of the grooves for excess wear, i cant tell by the pic if they are worn

i guess the point im trying to get across is if he's already put a crank,bearings, jug, and piston in it, then the kid will be verry dissappointed to find out later that the tranny is garbage. you only showed a few gears. are they all damaged like that? or just the ones in the pics? replace just the ones in the pics if they are the worst and at least consider getting the drum maybe even second hand... it would be an even greater shame if he's invested so much so far, only to have it let him down sooner rather than later. as is, and under moderate riding/racing conditions i would say that there is a strong chance that it would drop out of gear.

I completely understand your point. Honestly, I want to replace them so that I can sleep better at night knowing that I didnt return him a time bomb. I think I'll explain to him the risks and let him make the decision. After all, it is his money. The two gears I showed in the pics are the worst. Some of the other driven gears show similar wear, but nowhere near as bad. I agree that the MINIMAL replacement should be those 2 gears if he is on a tight budget.

EDIT: actually looking again at your drum it doesnt seem TOO bad. other than that dent (who knows what that was caused by) inspect the peaks and valleys of the grooves for excess wear, i cant tell by the pic if they are worn

Aside from the weird dent, the shift drum looks fine. I dont see any grooves and only minimal wear.

I think I'll explain to him the risks and let him make the decision.

well said... for what its worth i dont think it will grenade his engine, i just think that if he's gonna do moto that he understands that it can drop out of gear on him, which can cause some dangerous situations. im guessing that those gears are 3rd and 4th on the driven side, and i do think that he can get away with replacing those. i would also recomend the 450 detent spring for more positive shifting, its cheap assurance.

I completely understand your point. Honestly, I want to replace them so that I can sleep better at night knowing that I didnt return him a time bomb. I think I'll explain to him the risks and let him make the decision. After all, it is his money. The two gears I showed in the pics are the worst. Some of the other driven gears show similar wear, but nowhere near as bad. I agree that the MINIMAL replacement should be those 2 gears if he is on a tight budget.

Aside from the weird dent, the shift drum looks fine. I dont see any grooves and only minimal wear.

that's all you can do. ultimately it's his decision

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