CLUTCHES 101-Part 1: the 400/550/600s with pics

:idea: Hi all , It seem's from looking in the 550 workshop manual , and having stripped my clutch that there is no spring that goes in the middle of the clutch plates !! Is this UK spec or has mine been lost over time ???

 

In the USA-market bikes, there should be ONE. Some of the Euro-spec bikes had two, as in the diagram before I corrected it.

Look closely at your friction plates. There should be one with a slightly larger ID, which is where the spring was supposed to be. If not, it's possible that somebody has already replaced the stack with aftermarket parts and eliminated the spring and its special friction plate. More likely it got lost along the way.

How necessary is it? I honestly don't know. The bigger bikes don't have any, and their clutches work fine. I suspect it and the tabby plain plates are anti-rattle measures rather than function-improvers.

 

Fitz,
Great tutorial; thanks for posting. Not sure if I'm just seeing things, but in the early disassembly pics, it sure looks like the alignment dots on the hub and pressure plate were 180 degrees out. Were they? If so, did the clutch function properly? And if so, was the culprit the same guy who used the hardware store bolts? Thanks again for all your help here.

 

No, he had that right. By the time you see the dot in the disassembly pics, the hub had been rotated.

The clutch wasn't working correctly; but it was due to the hub being LOOSE (thank you Yamaha for the tab washer) and 30-year old plates.

 

So, i took on the job of replacing the friction plates on my maxim after going through this how-to and everything was going perfectly until...

I had one of the five pressure plate bolts break off!

I was using a star pattern to tighten everything evenly, a torque wrench so that i didn't go to far, and had not had any problems up to this point. Now, i've got half of the bolt stuck inside the whole it screws into with no idea how to get it out!

Does anyone know a way i can get myself out of this blunder!?

Any help would be greatly appreciated

 

Sure. Take it back apart and unscrew the broken-off piece. The screws don't bottom out, it should turn freely.

If it won't easily back out, hit it with a small reverse drill-type screw extractor. As soon as it gets a "bite" the screw will back right out.

Hindsight always being 20-20, this is why new bolts are recommended.

The type of extractor I'm referring to uses a reverse-drill bit: http://www.sears.com/craftsman-7-pc-dri ... 952157000P

 

Thanks! I'll give that a try! Guess i was a bit over zealous in getting to work on the friction plate replacement to wait again for new bolts. Now, i know better.

 

see i always wondered, cause when i replaced my friction plates and bolts, i actually got the bolts from the yamaha dealer for 1.75 each, even though the old ones looked brand new when i pulled them off. makes me come to remember how the old ones were bright zinc looking silver color and the new ones were black/dark brown colored.

 

Well, I got the bolt extractors and got the old bolt out. Came out without a problem! Once the new bolts and washers came in i put everything back in the way you described, oddly enough though i had the same thing happen with a brand new bolt from the yamaha dealership. Yep, that's right, for some reason the brand new bolt cracked. I do have a good accurate torque wrench and all of the other bolts tighted in a star pattern at the right force, but when it came to this same spot i felt the bolt start to break.

I was able to back it out before it broke completely, but just barely. I tried using another old bolt and had the same problem. It wasn't until the third bolt of the night that i had one go in, all be it at about 1 ft./lbs less than the recommended torque.

After the second bolt broke i took a light and examined the threads; they all seemed to be in good condition. So, needless to say, i am quite confused as to what caused this problem. I have everything put back together now, with a new gasket and oil back in place, but have not started it yet.

 

What spec where you tightening it to?

I noticed when doing my clutch for my turbo seca, chacal actually sells a higher grade bolt that what I pulled out of my bike (w/ 6k miles, it's safe to assume it was factory).

 

Are you sure the pressure plate is properly oriented to the clutch hub? There is a dot cast into the pressure plate that has to align with a dot cast into the clutch hub. If not properly aligned, you could be getting a side-load on that one bolt that is breaking it. The pressure plate will "fit" if incorrectly positioned; but it doesn't really fit right.

 

I'm putting these bolts in at 7.2 ft./lbs. everything is oriented correctly as far as I can tell. The dots are lined up and everything fit snugly back into place.

 

Good news, though those problems were present in the bolts going back on everything started and operated very well!

 

Thanks a ton, bigfitz. Great instructions and photos. This was my first clutch job ever and it worked perfectly on my first attempt. You are the man!

 

After tightening the 5 bolts on the pressure plate, should the pullrod with teeth still be loose and be able to turn freely inside the pressure plate? Thanks in advance

**EDIT: update 8pm. EST: To answer my own question, I think the pullrod should be loose beneath the pressure plate because the manual(s) as well as your How-To thread here doesn't refer to aligning the pullrod in the correct direction before tightening the pressure plate. So after dinner I finished re-assembling the clutch (entire different assembly) and now it rides & shifts smoothly. I'll update my own thread later this evening after I get the first ride of this season outta the way!!! **]

 

Not only should the pullrod be free to rotate, it should pretty much "flop about" in the pressure plate until it gets "picked up" (and guided by) the bore in the cover.

 

Bigfitz, what do you recomend for a torque wrench?

 

Adding-in my experience; my seca came w/ PO installed barnett clutch pack, which has no boss spring. they we VERY worn out when I got it. They used the original plain plates though, so maybe without the full set it needs the boss spring?? Anyhow I ordered one as my new clutches have the one larger ID friction plate. I think the vibration dampening sounds like a pretty logical theory for it's purpose, it's not very strong for much else...

Also I've seen many other bikes which all have similar springs, but usually between each set of plates (instead of just one or 2 in the middle) to help them evenly split up and lubricate at idle. Also the tabbed plates or similar mechanisms i've seen in other clutches to help spread the fluid and prevent overheating and glazing, to have them all unevenly spaced moves fluid around better.

Deep Thoughts.

 

So what if you can't get the clutch to engage at all? I haven't opened it up yet, but last time I ran the bike, I noticed a little bit of creep with the clutch engaged. Now when I try to go into first, it jumps forward and stalls as if I didn't have the clutch engaged at all. Did I manage to fuse the friction plate or something?

 

Hey man,,
how do you like this new forum.. I am digging it man !