Clutch Slippage?

[Pungo]

Lately I've noticed a fair amount of clutch slippage in second gear when getting on it pretty good. I'm curious if others have experienced this and if it's normal or not. It only seems to happen in second gear. I'm not riding the clutch - just a clean shift from first to second under hard acceleration. BTW, it's an '01 750 with about 13K miles.

Any thoughts would be appreciated!

[professorman]

Maybe the clutch might be going out. The reason you probably dont feel it in first gear as well is beacause you probably havent gotten on it in 1st like how u do in 2nd. Does it slip at higher RPMs or does it slip right as you shift to 2nd?

[KRAZYKAT]

I DONT NO but ive heard dat changing da oil to a fully synthetic oil,sometimes results in slippage.has u , or anyone changed ur oil before this has happend?
i cant say from experience though.i changed my oil to dat fully syn. mobil one oil dat cyber poet recomended,and i didnt get any slippage. but i guess if u use da wrong one it will...

[The CyberPoet]

Although the stock clutch pads should be good for at least 20k miles in an urban environment (lots of shifting, stop-n-go traffic) according to Suzuki, there are a few things can cause slippage earlier. The big ones are glazing (from spinning the engine way up and dumping the clutch, such as trying to wheelie or burn-out), and/or using an API SJ/SL/SM rated motor oil (or any oil with the words "energy conserving" in the API oil-rating ring).

In the case of the oils mentioned, they contain special friction modifiers that can bind to the clutch plates/pads to keep them from gripping properly. This is a particularly annoying issue, as you have to get all the oil out of the system (a couple oil changes almost back-to-back, including dumping the cooler each time) AND replace the clutch parts normally (I haven't seen any chemicals that will wash off the energy conserving additives sucessfully out of the pores of the clutch pads, but there may be something out there that can).

In the case of glazing, you basically have burned the surface of the pad, which makes it far less grabby than it should be. Depending on how thick the pads still are, you may be able to get away with lightly sanding the surface with a very fine grit emory cloth to remove the glazing.

There is one other possibility that comes to mind if the problem only happens just as you shift into second (and won't repeat if you are in 2nd already & decelerate down close to idle then get on the gas), and that is that the 2nd gear sprocket isn't engaging correctly (so it's spinning over where it's supposed to mesh before catching). This is usually a result of bad shifting (or mechanical damages as a result of bad shifting habits) -- shifts should be done very quickly, with a hard clean snap, and without any positive throttle (i.e. - the throttle should be causing the RPM's to be falling when you physically engage the shifter for an upshift).

Good Luck!
=-= The CyberPoet

[Pungo]

That's for the help. It sounds like it may be the second situation you described. It's only slipping when going from first to second under hard acceleration. It sounds like I'm letting the clutch out very slowly although I've already fully released the clutch. No problems when already in gear or downshifting or in any gears other than second. I'm using the recommended non-synthetic Suzuki brand oil straight from the dealer and it was changed less than 1,000 miles ago. I don't think I've been overly hard on it - no wheelies or dumping the clutch or burn-outs) but I've had the bike less than a year and it's hard to say how it was riden in the past. I don't think it's a big deal right now but I'll keep an eye on it.

Thanks again!

[The CyberPoet]

I'm using the recommended non-synthetic Suzuki brand oil straight from the dealer and it was changed less than 1,000 miles ago.

If you still have a bottle of the stuff, check the API rating. Suzuki USA switched their "Suzuki brand oil" to an API SL rated oil as their standard oil about 15 months ago and most dealers didn't notice the change. I think it's actually their automotive oil being sold through the bike dealers now. The Kat is not designed to run on API SJ or later, and if you search KR, you'll find an interesting letter the API sent me specifically in response to that question.

Cheers,
=-= The CyberPoet