Second gear slips when the bike is very hot

[jalingo]

hi Guys , greetings from south France

maybe this topic is already been discussed , but i don't know the right terms to explain my problem

here in France we say the "CLUTCHES SLIPPING" when you feel the acceleration is not homogenous

i hope you guys understand me .

The beast has 58K miles ans is a Gen2

last week i did a clutch purge with a Yamaha DOT4 , i put too much and felt the second gear slipping when the bike was hot

a friend told me to remove little bit of liquid and is what i did , then everything became normal ( is what i thought )

today i went to cruise in the mountain, did almost 200 kilometers ,

when arrived in town , bike was hot and when i start at the green light , i feel the first gear and the second gear slipping , but not all the time !!

but when i cruise in 3rd and 4th and 5th and i accelerate , nothing happen is smooth as usual

this happened only when i accelerate in 2nd gear most of the time

does the clutch discs are dead ?

2nd gear clutch can be at the gates of hell ?

or some air in the clutch system ? due to my purge ? and this making a slipping in the discs

thanks guys for the future answers

 

[Steve in Phx]

Did the clutch slip ever happen before you added the new fluid?

 

[gapiob]

Hey, hello gigi!

 

[jalingo]

Did the clutch slip ever happen before you added the new fluid?

Well !! i'm not sure !!

i felt it slipping a lot after the oil changing , but before i think no , or maybe little bit ,

but the problem in the beginning before the clutch oil job,was that i didn't do a good acceleration in second gear , i ride very very cool and not a fan of a big acceleration at the green light

so frankly i dont know !

before this problem i was very interested in a upgrading on the discs for having the smooth clutch command , i posted something about this upgrade as well

 

[rPGoatBoy]

Unfortunately, it sounds like you're the victim of your shift fork(s) being bent/2nd gear dog wear. Clutch slippage would be a smooth loss of power transfer while a slipping gear dog situation would be more like an abrupt fraction of a second loss of power to the rear wheel.

Does your situation sound like this?: https://www.youtube.com/watch?v=q9h0b-Sbn9u

Ignore the shitty cell phone camera quality of the video an pay attention to the sound at approximately 11 seconds.

I say unfortunately because the fix for this is pulling and splitting the motor to replace some transmission parts. There are instructional threads with pictures on this forum from members that have had to do it, myself included.

Good luck!

 

[TomInPA]

Did the clutch slip ever happen before you added the new fluid?

Well !! i'm not sure !!

i felt it slipping a lot after the oil changing , but before i think no , or maybe little bit ,

but the problem in the beginning before the clutch oil job,was that i didn't do a good acceleration in second gear , i ride very very cool and not a fan of a big acceleration at the green light

so frankly i dont know !

before this problem i was very interested in a upgrading on the discs for having the smooth clutch command , i posted something about this upgrade as well

What motor oil are you using? Energy conserving oil with friction modifiers can cause clutch plates to slip, especially when hot. As far as the clutch fluid goes, you should be able to see the meniscus of the fluid in the sight glass on the master cylinder. If you can't see the fluid surface, you may still be overfilled. The fluid will expand slightly as it heats, so the top of the master cylinder should have an air gap which prevents this. Remove fluid from the top of the clutch cylinder using a syringe to suck out just enough, then replace the seal and lid. Simply bleeding fluid through the brake caliper will not leave the air gap in the cylinder.