Clutch repair failure

You were right the first time. 90 inch-pounds = 7.5 foot-pounds.

Do you have any suggestions?

Nathanb wrote: Do you have any suggestions?

Regarding the clutch slippage or the bolt breakage?

I guess my first question overall would be what led you to replace the clutch cable and actuator in the first place? Were you experiencing some slippage symptoms?

I would like to say that's the best information I got yet on your profile page. I will do it for the seventh time thank you.

Yes I was experiencing some slippage and started messing around with that the bolts on the actuator arm and it's snowballed.

I guess I obviously need to know about the bolt breakage first . Any ideas? What could possibly cause the bolts to snap before three and a half ft lb. I snapped two bolts and replaced them with zinc bolts and I didn't even get 3 foot pounds. I would have four of the bolts and a right when I think it was about to click it would break. Now I am am afraid to tighten them anymore. I also need the proper bolts not zinc. I have no clue where to find them. Partzilla? I will look into that. Thank you for your time. I guess I am learning I hope. By the way things are going I guess if I find the bolts I'll order ten of them instead of five.

It's common, on the Kz550's, to experience some slippage if the oil level is even a little bit too high, especially right after an oil change.

Yes the adjustment procedure in some of the manuals might be backward. If the actuator has those three little ball bearings, then you should go by that graphic on my site.

In all the years of working on Kz550's, I have never seen any actual clutch wear on the plates. They pretty much are always within spec as long as they haven't been run out of adjustment... in which case they can be burnt looking or warped.

The springs, on the other hand do need to be replaced occasionally. There is a pressure/length spec in the manual.

I've found the stock friction disks and plates work better than any aftermarket options for a stock motor and stock springs, and give the best grip with a light clutch lever. 20 years ago I asked some speed shops which aftermarket clutches were best for Kz's and they said none. They were adamant that factory clutch disks were best and they were right,

As for the bolts breakage... make sure there is no oil at all in the bolt holes, They can cause a hydrostatic lock and the bolts will shear if not break the clutch basket. I use a little paper towel formed into a wick to absorb the oil out.

If you use a torque wrench make sure it's perfectly calibrated... but by now you probably have a better "feel" for it.

It uses plain steel bolts. Stainless is harder but not stronger. You probably don't want zinc in there.
It's far better for the bolt to break than for the threads to strip... be careful of that, so you probably don't want super strong or super hard bolts.

ebay might get you the bolts if you can find the part number. The factory bolts are porbably used on a ton of bikes so you can get the actual correct part. I recommend that and use "feel" until you can get a known calibrated inch-pound torque wrench.

That would make all too much sense. A friend of mine gave me the bike and the first thing I did was change the oil iand the spark plugs. The oil was like grey but did not smell burnt ,it was bad. The spark plugs weren't that bad but I still replaced them. After the oil change that's when everything went bad. So I thought the clutch plates were shot . So I replaced the clutch plates and springs. the originalclutch plates and springs looked better than the ones I bought but I still replace them and saved them. What do I do about the bolts? I don't want to ride worrying about the bolts. I want to do it right. And I don't want to do everything 10 times.

And yes I changed the filter also.

I do not see a mention of the oil you used. Is it motorcycle specific or diesel oil?
If it is automotive oil, the friction modifiers can cause clutch slippage, though not usually as severe as you have mentioned. It could be a contributor, though. An easy way to know if the oil is ok for wet clutch applications is to look for JASO-MA certification on the back of the bottle.

Alright, let's clear this up.

What are you using for a torque wrench? Is it 1/4", 3/8" or 1/2" drive?

There is no way that bolts should be breaking at a whopping 3 ft.-lb. of torque. Unless they are made from Mozzarella sticks. :laugh:

Post pics of the torque wrench and the settings on the dial.

What’s the torque rating on a McBolt?

Sorry no help but I laughed at mozzarella cheese stick bolts.

Continue

Highway Magician wrote: Alright, let's clear this up...........There is no way that bolts should be breaking at a whopping 3 ft.-lb. of torque. Unless they are made from Mozzarella sticks. :laugh: .

Exactly! Breaking bolts at 3 ft-lb doesn't make any sense at all. Obviously something is very wrong. 3 foot pounds is equal to 36 inch pounds and every 6mm bolt should be tightened to roughly double that! Ed