Clutch Slippage

[kkent66]

I have a 2006 RSV with 54k miles. March of 2012 I upgrade my clutch spring with a PCW heay duty clutch spring. I did not upgarde my friction plates as the guy at PCW said those should be good for 75k miles. Here is a list of all mait I have done the past few months;

 

Flushed cooling system

Replaced Spark Plugs

Changed oil & filter

Changed final gear oil

New Rear brak pads

New Front brake pads

Flused front and rear brakes with might vac

Flused clutch with might vac

Installed HID ligt

Istalled a tune trapper antenna

installed a power amp and new polk speakers - front and rear

Sync carbs with my new morgan carb tune

Installed an iphone charger directly wired to battery with relay and on/off switch

My bike is running better than ever but I still get a little bit of slippage when I roll hard on the throttle. I am wondering if I need to replace friction plates?? No problems shifting and if I dont "floor" the accelerator no slipage.

 

Any thoughts would be greatly appreciated.

[TheKid]

What kind of Oil are you using? The different Oils can cause slippage as well. Did you check your friction plates when changing the spring? Did you do the upgrade to the last plate to make it a whole friction instead of a half?

[WildBill1]

Clutch slipping is often the result of using improper oil in these engines. They need m/c oil not automotive. Don't know if you were using auto oil with friction modifiers or not, just saying. Once the plates have slipped very much its best to just change them out.

 

Bill,

[SilvrT]

If you just replaced the spring and the clutch was slipping before that, then you should have either ...

 

a) removed all the plates and friction discs and scuffed them with emery

b) replaced the friction discs while at same time scuffed the plates.

 

Actually, this should have been done regardless if it was or wasn't slipping beforehand.

[Flyinfool]

Under normal conditions the friction plates may be good for 75K. Depending on how bad, long, and often the clutch was slipped before you replaced the spring can have a huge impact on the overall life of the clutch.

It is possible to wear out a set of disks in 1 day with a lot of slipping.

 

Also as mentioned, the choice of oil can have an impact on clutch slippage.

 

When I did my spring upgrade I did the day after the first sign of slip, The only way to tell if the plats have life left is to measure their thickness. New plates are 3mm (.118 inch) thick, the wear limit is 2.8mm (.110 inch) thick. My plates were at .117 thick at 40K miles so I put them back in. If you are in there measuring them I would replace at .113-.114 which is 50% of life.

 

The biggest things that will shorten clutch life are lots of parking lot driving in the friction zone, hard riding, and heavy loads like a big trailer.

[kkent66]

Should have put this in my original post - I use Mobil 1 racing 4T 10W-40.

 

I do ride 2 up most often but I do not pull a trailer!

[bongobobny]

There is a heavy duty clutch that Yamaha offers that is a good idea to install when you take everything apart to clean and check. It has more area and you discard that pesky retaining wire when you install.

 

Your choice of oil may be a part of the problem as well. As mentioned, any auto oil with friction modifiers will cause the clutch to slip. Motorcycles have "wet" clutches with oil circulating in them as opposed to a car clutch which is external to the motor and has no oil on it. I would do some research on the oil of choice and see if it contains any friction modifiers. If it does, change it immediately and change it again after a couple hundred miles or less prior to working on the clutch, and drain that oil too before you reassemble. You want to get rid of any traces of friction modifiers. You should use motorcycle oil, or if you want to save some money, diesel engine oil works excellent such as Delo, Rotella, etc.

[Flyinfool]

The oil you used, Mobil 1 racing 4T 10W-40, is a motorcycle oil that specifically states it is for use with a wet clutch. It "should" be fine. But I have heard of some people having issues with full synthetic motorcycle oils that "should" work.

 

It is possible that either you wore out the clutch back when it was slipping and or it got glazed while it was slipping. Remember there is only .008 inches of thickness between a new and a worn out friction disc. That is only .004 per side, about the thickness of a piece of paper. The only way is to measure each disc. Glazing is not always visible to the eye, a light sanding of all friction and steel surfaces will ensure no glazing.

 

Fortunately it is really easy to service the clutch on these bikes.

[bongobobny]

Well, there ya go! Jeff did the research for you!!