RPM vs. speed differences....What's up with this? : KawiForums.com Kawasaki Forums: Kawasaki motorcycle forums

amad · 04-06-2008, 09:28 PM

So I was riding my 08 250 today for a couple hours. I noticed in 6th gear the rpm was different for the same speed at different times. When I first started riding 60 mph was turning about 7k rpm. Later in the ride 60 mph seemed like it was turning too fast, so I looked and it was turning about 9k rpm (yes it was it 6th gear. I checked and also counted down as I geared down to first.) Then later, after the bike had sat for a while, it was back down to about 7k rpm at 60. What would cause this? Anyone else notice this issue? Something with the bike being hot?

TheDuck · 04-06-2008, 09:55 PM

Maybe you miscounted the gears... I know I have.

But I'll just go out on a limb and throw this one:

Have you by any chance noticed your clutch slipping at all, maybe the clutch cable is adjusted a little too tight.

kkim · 04-06-2008, 10:02 PM

Check to see if you have sufficient play in the clutch cable at the lever.

lol... duck, you beat me to it.

amad · 04-06-2008, 10:16 PM

I don't think the clutch was slipping, because I gave it more gas and the revs didn't go up without the bike speed going up. I'm positive I was in 6th. I tried several times for a higher gear, but it wouldn't go. And I clicked down 5 times to 1st. I'll check the clutch freeplay tomorrow. I'll let you know. By the way, it's the first time I've noticed this and the bike has almost 300 miles on it.

amad · 04-09-2008, 09:31 PM

Well, I checked the clutch cable and I think that may have been the problem. It really had no free play at all. I adjusted it as far as it would go and now it has a little bit of free play in it. I think that maybe the clutch wasn't completely engaging (almost, but not completely). And that's why the bike still was pulling, but turning more rpms than it should. I'll keep an eye on it.

kkim · 04-09-2008, 09:35 PM

If you cannot get enough adjustment at the lever end, try looking at the other end of the cable where it enters the engine case. There is usually an adjustment there. The one at the case is used for coarse adjustments and the lever is for fine adjustments. Good to hear it was something relatively simple.

amad · 04-09-2008, 09:45 PM

Quote:

Originally Posted by kkim

If you cannot get enough adjustment at the lever end, try looking at the other end of the cable where it enters the engine case. There is usually an adjustment there. The one at the case is used for coarse adjustments and the lever is for fine adjustments. Good to hear it was something relatively simple.

Good to know. Thanks! I'll look at that next if I need more adjustments.

amad · 04-12-2008, 10:44 AM

IT'S STILL DOING IT!!!

I adjusted the lever to have (what I thought was) some freeplay. Went out riding and after about 30 minutes, the rpms were too high in 6th gear. When I got home, I wiggled the freeplay and watched where the clutch cable goes into the clutch. The cable down there still moved a little and maded a slight clicking sound. What that be engaging the clutch a little still? I might try to adjust it down where the clutch cable goes in.

Also, exactly what rpm should I be turning in sixth gear going 60 mph? Does anyone know exactly, so I can have a reference point. Mine has varied somewhere between 7k and 9k. I think the 7k is more what it is supposed to be.
If you're not sure, maybe sometime today while you are riding, make a quick check of rpm at 60 and let me know.
Thanks everyone.

HKr1 · 04-12-2008, 11:18 AM

Yeah thought 7000 -7200 was like 60.
So is it just the tach higher, or you can hear the rev's go higher. If you are, on/off the gas, they still stay at the higher rpm?

amad · 04-12-2008, 12:10 PM

The tach is correct, I think. When it does this, I can hear the revs higher than they should be. It only started doing this when I had about 270 miles on the bike. And it only seems to do it when it has been running for 30 minutes or so.