Clutch question

[wolffie]

With the clutch cover, pressure plate, and pads (friction and metal) removed, is the basket supposed to have any sort of "play" or movement if tugged by hand? mine certaintly has about 2- 4mm of play.

Also, this is probably an obvious answer, but if my pressure plate has grooves in it from the clutch springs, is that a solid indication of necessary replacement? that probably isnt healthy haha.

I had a race over the weekend, and my clutch slipped bad, my machine lost power, and then my red light came on lol. i shut the quad off, and when i tried to shift back up to speed my clutch would not engage in any gear; it was as if i was in neutral the entire time. so basically, i understand that i am in need of some fixing lol. I havent torn the clutch apart past the removal of the plates but i am pretty sure im going to be replacing some stuff. what do you guys think based on this information? i am definitly feeling new plates, pads, and probably pressure plate but i havent fully torn the clutch apart either.

[daddio]

Is it a stock basket?

[wolffie]

yes, as of right now all clutch components are bone stock.

[daddio]

Take the basket assy off, and if you can hold the basket and move the gear (at all) by twisting it in opposite directions with your hands, then it's also time for a new basket assy.

FYI........ The springs (on the backside of the clutch basket), spring pan, spring keeper and primary gear, all have to be in good condition to put an aftermarket clutch basket on. I put a Hinson basket on a wore out assy, and one of the springs broke, causing catastrophic engine damage.

Before you get too carried away, measure your clutch friction plates, and see if they are in spec.

Are your metal plates still silver colored?

I've never seen a pressure plate with grooves in it from the springs. You may have other issues.

Can you post pictures?

[wolffie]

yep i can have pictures later today. Thank you daddio!

The pads look worn (they are stained dark brown and the fibers look smooth) but "eye balling " them to a new set of pads, they look to be of similiar thickness. The metal plates are not silver colored they are stained a dark brown. I would imagine both components are shot.

I had changed the clutch pads, plates, and calbe about 3 races ago, but i had NOT changed the springs in about a year; that includes about 6 races and alot of hard racing. i suspect the wearing springs may be the case of clutch failure.

I called my Yamaha mechanic (who is a very knowledgable guy), and he said that minimal grooves in the pressure plate are not uncommon, and some slight movement in the clutch basket is ok. He said more than likely i should put in all new fiber pads, plates, and stiffer springs and see what occurs from there. He also mentioned that too much cable freeplay could have been the case in this scenario, but i had sufficient freeplay so i dont think it was that.

I have only torn apart what i have mentioned in my first post, but i plan on tearing it down further through the clutch assembly.

[daddio]

Do you run an aftermarket case saver? Sometimes the lever on the clutch actuator is 1 serration off, and the lever hits on the case saver, and it won't allow the clutch to fully engauge, causing it to slip. We get 10-12 good hard races on a set of frictions, and we run a Rekluse, which is much harder on the clutches.

I agree with your mechanic, that a little movement is acceptable, but the amount your talking about, is not.

Take a good look at the springs on the backside of the clutch basket, and if you see any wear, on the springs or retainer, chuck it.

I had so many problems with the stupid springs, I switched to the '07 YZ clutch basket assy. (it uses rubber dampeners) Note: you also have to change the gear on the end of the crank and the washer inside the clutch basket.

[wolffie]

i will tear it down and inspect the springs to come up with some solutions. i dont run an aftermarket case saver, but i beat the living hell out of my clutch; i raise harescrambles and i am constantly clutching, more so than when i fan the clutch in corners for MX.

I'll let you know what i come up with! thank you very much for your help

[daddio]

Originally posted by wolffie
i will tear it down and inspect the springs to come up with some solutions. i dont run an aftermarket case saver, but i beat the living hell out of my clutch; i raise harescrambles and i am constantly clutching, more so than when i fan the clutch in corners for MX.

I'll let you know what i come up with! thank you very much for your help


With that in mind, if you have any play at all between the clutch basket and the gear that is rivited to it, you need to replace the whole clutch basket assy.
For reference, I have an '07 motor, torn apart in my shop right now, that threw a chain and broke the case. It has been ridden and raced mx for about a year and a half.............. The basket is still absolutely tight on the gear.

I've lost motors because the clutch dampening springs broke or came loose in the retainer, so I'm a little cautious.

[d kelley]

Daddio, let us know the part #'s your talking about. I came up with different #'s for the basket but not the washer or the primary gear. I have had the clutch basket springs come out too and it is not pretty or cheap when they come unglued inside the cases. BTW, are you WORCS #310?

[daddio]

5XD-16150-60-00 PRIMARY DRIVEN GEAR COMP.
2S2-16111-60-00 GEAR, PRIMARY DRIVE
5XD-16154-00-00 PLATE, THRUST 1

These are the parts I used to swap to the '08 YZ450F clutch basket assy on a 2006 YFZ.
All other stock or aftermarket YFZ parts work with the clutch. Inner hub, actuator parts, pressure plate, friction and metal disks, etc.
This will give you a little taller gearing to the transmission, but it seems to work better.
The stock YFZ thrust washer can be used, but the way the basket is made, you really should use the YZ one in the YZ basket. This washer controls how the oil is distrubited in the clutch assy.
I ran a YFZ washer at first, and it worked fine, but it left a rub mark on the backside of my inner hub.

d Kelly............ I'm WORCS # 192 in the open B class and my son is #191 in the Pro class. We don't race WORCS that much.

[d kelley]

Thanks, Daddio

[daddio]

Originally posted by d kelley
Thanks, Daddio

Your welcome............

I think #310 is Jeff M.