yz125 gear lever problems

[Yozzer]

My son has gone through his fourth gear lever in 3 months on his '07 yz125 (the original lasted him about 7 months and now 3 FX levers).

He's stripping the teeth on the lever - thankfully there's no damage to the shaft.

Is this is a case of being to heavy footed or is there an issue with this gearbox that can cause this to happen?

 

[rmc_olderthandirt]

There might be some damage to the teeth on the shaft. Having four levers twist out on the shaft would would certainly round off a bit of the splines.

I recommend making sure that you have the bolt tightened down as tight as possible to keep the lever tightly clamped. A phrase my dad used to say might apply here: "tighten it down until it breaks then back it off a 1/4 turn"

If the bolt is coming loose then you might do well to replace it with a longer bolt and put a jam nut on the other end. Make sure the bolt is a grade 5 or better, the cheap bolts will not take the torque that you will want to apply.

Rod

 

[Yozzer]

yz125

Thanks Rod - I'll check the shaft and change the bolt and see where we go.

I've gotten it as tight as possible previously but it just seems to come loose by the end of a 2hr Enduro.

Let's see how we go...

 

[fatboyslim]

try an MSR lever, the same thing happened to me and made it hard to shift into neutral then I got this MSR lever and it's been great.

 

[BSWIFT]

You might do a search on the transmission issues. Not sure if this included the 07 model but there was an issue. I would recommend an OEM lever available from the auction site, any YZ or YZF model will work. Tighten properly and check regularly.
I searched "yz 125 transmission" and here is one thread.
http://www.dirtrider.net/forums3/showthread.php?t=115906&highlight=yz+125+transmission

 

[atkken]

loctite (low strength) the bolt and tighten firmly
that cured mine

 

[tyler_43]

I had the identical problem on my yz125... tried msr shifters, sunline, stock... none of them worked, they all came loose by the end of a 20minute moto and sometimes stripped right off before I finished. Then I found a steel msr shift lever that was the same length and offset (it didn't have the upward bend though so I had to cut the front sprocket guard a little). I think the steel one was made for a yz85 I'm not sure. Anyways the steel one doesn't ever come loose on me... though if it did I'd be more worried as it might strip the shaft spline :|
If you're using aluminum levers try a steel one, and put a lock nut on the end as olderthandirt mentioned... you shouldn't have a problem then.