Weird Clutch Issue On 08 Yz450f

[yz125ohioracer44]

Ight, so my bike is giving me an issue that I've never dealt with nor heard about ever hah, so bare with me trying to explain this. So lets say I get to the track and I just start up my bike, the play in the clutch lever is set to how it should be(nickle width of play/space between the inside ends of the lever and perch). I let the bike warm up and go onto the track, as I do a moto(about 5 laps) I begin to notice the play in the clutch lever grows more and more as the motor warms up and then the play stops growing and stays where it's at(aprox. 6 times more than the play I started with). So I pull off to the side and re-adjust the play back to the nickle width of play and the bike is fine. I'll pull off and take a break for about 10-15 mins and let the bike cool down. After the break, I get back on the bike and there's no more play in the clutch, so if I go out and try riding it the clutch slips and I have to pull over and adjust it again and then after another moto I have to repeat the process. The bike has a new clutch in it and I just can't think of what it could be. I was thinking maybe the clutch basket is worn out but I'm not sure. Any help is appreciated :]

[grayracer513]

The clutch is getting hot, expanding, and moving the pressure plate away from the push rods, creating more play. When it cools down, the play goes away. You are either using your clutch too much, or have replaced your stock plates with a set of aftermarket parts.

[yz125ohioracer44]

So you recommend buying an oem clutch kit? I don't think I use the clutch too much...

[grayracer513]

OEM is a lot tougher than many of the available aftermarket kits, yes.

[yz125ohioracer44]

Do you think it can only be the clutch plates, not the basket or anything else? Thanks for the help btw.

[fastyz250]

i have a barnett clutch in my 06 and i love it, heat does not seem to affect it too much and it feels great. i have used barnett clutches in the past with great results

[i_wheelie_longer]

I had the same problem on my 08, but never had this problem on my old 06. I believe the 08 has one fewer clutch plate than the 06 to make for an easier clutch pull, but consequently more clutch fade. I'm almost positive you can switch out your 08 clutch set-up for the 06 style, but I am not positive on all of the parts you would need for the conversion. Anyone care to fill in?

But yes, I would first start off by installing OEM friction and steel plates and see if that solves your problem. OEM is certainly the way to go for clutches.

[grayracer513]

Yes, it's the plates causing it, and yes, the '07+ clutch is more subject to it because it's short a plate.

To convert to an '06 clutch:

https://www.thumpertalk.com/forum/showthread.php?p=7261940#post7261940

[todds924]

OEM is a lot tougher than many of the available aftermarket kits, yes.

Gray, That was a problem with my 08 also. The cure was to replace everything with an 06 set-up.

I got tired of the stock 08 set-up.

That was also a problem with my 2010 until I put the linger 2011 clutch arm.

[grayracer513]

That was also a problem with my 2010 until I put the linger 2011 clutch arm.

Did you also add a plate to the '10, or did you get it working well with 8 plates?

[todds924]

Did you also add a plate to the '10, or did you get it working well with 8 plates?

No I actually got the 10 working well with just changing the clutch pull arm to the longer 2011 part.

[yz125ohioracer44]

Thanks Gray, Is it worth going to an 06' setup instead of buying oem clutch plates and basket for an 08'?

[grayracer513]

The '06 is a more robust clutch, there's no question. The OEM plates, or premium replacements like Hinson, work better in either case, so don't think you can cut corners and get away with a cheap clutch kit by going to an '06.

If you need a basket, you need one, whichever setup you go with. In your bike you'd use the '08 basket either way.