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YZ250 2 Missed Shifts. Rebuild soon?

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Had a GREAT weekend of racing, however I made a couple mistakes in my last moto...

There were 2 instances where I weakly shifted up to 3rd and the bike didn't hit 3rd, but it also didn't hit a false neutral, it still had power (2nd gear) with what felt like a bit of a grinding sensation. Both times I quickly shifted up into 3rd and continued. From then on out I made sure to be firm with my shifts and didn't have any problems.

So what's the chanceability I'm in for a tear down within my next race or 2? Just trying to get a feel for what people have dealt with. All of my searches brought up past issues of false neutrals, typically meaning a bent shift fork... Again, my bike still remained in gear in a way I would describe as "2.5" because I could tell it wasn't in the right place (grinding sensation).

Let's hear your experiences!

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30 minutes ago, Sullysully said:

I might have experience this once or twice and have attributed it to rider error.

Well yes, I made the error of being a weakling with my shifts late in the moto... Was just curious on the potential for already causing serious damage.

I guess whatever the case, I'll just keep riding it as is until something gets worse. Full tear down at end of year anyway if it makes it that far.

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10 hours ago, SoCalMX70 said:

Well yes, I made the error of being a weakling with my shifts late in the moto... Was just curious on the potential for already causing serious damage.

I guess whatever the case, I'll just keep riding it as is until something gets worse. Full tear down at end of year anyway if it makes it that far.

Really hard to say without being there but I have had many missed shifts on a YZ but always 1 to 2 only. My guess is a bent fork but not entirely sure. I will say though a small semi cheap trans problem now can turn into $5-600 real quick, those gears are damn expensive. 

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Did a couple hours of practice yesterday at Glen Helen. Zero issues. No funny noises, nothing.

I'm sure as long as I don't shift like a wuss everything will be fine... And I'll get a chance for a visual inspection when I split the cases for a bottom end rebuild this Winter. At that time I'll replace anything that seems worn/rounded.

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15 hours ago, SoCalMX70 said:

Did a couple hours of practice yesterday at Glen Helen. Zero issues. No funny noises, nothing.

I'm sure as long as I don't shift like a wuss everything will be fine... And I'll get a chance for a visual inspection when I split the cases for a bottom end rebuild this Winter. At that time I'll replace anything that seems worn/rounded.

Bent shift forks usually can’t be spotted by eye. They have very small tolerances 

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How many hours on your bike?  I usually see third gear drive gear dog start to wear around 80hrs and will cause it to spit it self back into 2nd under load.  After doing this for a while, you'll start getting a false neutral.  I've done quit a few YZ250 tranny rebuilds and third is usually the first to go as it's the most commonly used gear.  Also, if your YZ is pre'15, upgrade the shift index roller lever the he solid roller type ('15 and up).  The older lever had a ball bearing which was prone to shattering and would spread debris in the tranny, not to mention odd shifting symptoms.  

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6 hours ago, dshissam said:

How many hours on your bike?  I usually see third gear drive gear dog start to wear around 80hrs and will cause it to spit it self back into 2nd under load.  After doing this for a while, you'll start getting a false neutral.  I've done quit a few YZ250 tranny rebuilds and third is usually the first to go as it's the most commonly used gear.  Also, if your YZ is pre'15, upgrade the shift index roller lever the he solid roller type ('15 and up).  The older lever had a ball bearing which was prone to shattering and would spread debris in the tranny, not to mention odd shifting symptoms.  

'16 X converted to regular YZ transmission at about 25 hours. Has 118 hours on it now.

I'm sure I'll end up replacing 3rd, any of the adjacent gears, shift forks, and whatever small parts (circlips, etc) at the end of the year. Even if only slightly worn, just going to get it all out of the way while I have it in pieces. So I can get another 100+ out of it.

And yeah I'd say I'm in 3rd 70% of the time at any given track. 2nd in the corners, 4th on long straights.

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Don't forget to check the simple stuff.  That little bolt that tightens the shift lever on the shift shaft is made out of cheese.  When in stretches and gets lose, the slop in the lever can result is missed shifts and other weird issues.  Check that first, and if it comes loose, replace it with a hardened M6 cap screw (any hardware store will have them).  You can really crank those on tight, and they seldom need to be re-tightened.  

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