Help! Slipping clutch??

[TheJeepGuy]

The bike will take off fine, pulls... okay I guess considering I had been riding a 600 earlier today(can-am quad not streetbike). But the problem lies on the highway. Doing 70 today tucked in like a baby (it was raining) the 250, 2008, with 1300 miles was redlining just to maintain 70. Good thing I rode the bike out in the sticks, because anyone behind me would have run me down going that slow. The bike is in immaculate shape, only has 1300 miles, and is garage kept, so I'm not sure what the problem is other than maybe a slipping clutch or stretched cable. Please advise.
ALSO, cable screw was sticking out about... 3/8 inch of exposed threads. So theres something to consider.

[MrAtom]

Make sure its adjusted properly.

http://faq.ninja250.org/wiki/Adjusting_the_clutch_cable

Also, if not, its probably just your clutch springs. Replace em with EBC's. They're good stuff.

[TheJeepGuy]

Let me pose this question then, knowing multiple friends are excellent mechanics, would you buy a Ninjette with 1300 miles and this single issue? and assuming its clean clean chain, no grease etc. (no drop evidence) what would you say is a fair price?

[Alex]

100% sure you were in 6th gear?

[TheJeepGuy]

100% absolutely positive.

I often check when riding just because as a track guy, when you call on the power that's not in whatever gear.. its a let down.

[dcj13]

Any chance the clutch cable needs to be adjusted?

[TheJeepGuy]

It's a possibility. I only had a few min today. And I always go over a buy twice. You're always excited the first time. So I'll be back looking over it Saturday.

[Floki]

stock gearing?

[TheJeepGuy]

Bike is bone stock. Even the front tire is stock.

[Alex]

/moved to new-gen tech

[Ghostt]

Assuming the clutch cable is properly adjusted, it could be the wrong kind of oil causing the slippage, the bike uses a wet clutch, so if the oil is not the proper kind, could cause slippage.

Some oils contain additives that while work for car engines to be super slippery, are a no-no for wet clutch, any 10w-40 to 20w50 rated JASO-MA/MA2 oil will do just fine. Shell Rotella synthetic is safe, and popular choice.

Personally I'd change the clutch springs themselves now, as they are the weak link in the clutch set-up, the clutch itself is more than capable, Kawasaki used it on the bigger bikes like ZX1000 etc.. it's the springs you need to change, this should be on the list of must have IMHO.

Upgrading to performance clutch springs by Ghostt

Choosing Clutch Springs

Barnett aftermarket clutch springs for a 1985-1989 ZX-600, Part # 501-50-05055. You can view them online at the Barnett catalog, here: http://www.barnettclutches.com/produ...&clutch_cc=600 They can be ordered through your local dealership, or at a number of online sources. Here is one such online catalog: http://www.exoticsportbike.com/6001.htm

Another option is the EBC CSK10 (see http://www.ebcbrakes.com/motorcycle_..._springs.shtml). This kit isn't quite as stiff as the Barnett, but is better than stock and usually a little cheaper. The kit does include six springs, while the ninja 250 only uses four.

Category: Clutch & Transmission

Below you can see the difference between the stock(yellow stripe) vs hd springs(red stripe) themselves, they are thicker, and a little bit longer. And no need to worry about it making the clutch too stiff, remember the Ninjette only uses 4 not 6, even more of a reason to upgrade to better springs.

I have done this on both my EX500 and Ninjette bikes.

[TheJeepGuy]

Update:
Threaded the cable in about 2 turns and the rpms were stable and the bike managed to muster about 80 before I couldn't see anymore. Should have worn my goggles instead of my glasses. Lesson learned.

[cadd]

The cable should have a few mm of free play before feeling any tension. Is that how you adjusted it? I assume you rotated it clockwise (to loosen the cable a bit)?