My 2002 does the same thing, not as bad though. It's the Carb.
Slight Surging while Cruising around 4K and Jumpy Idle
So when I try to cruise at a constant speed (usually in 1st or 2nd gear), I notice slight surging in the power. I don't think it's the roads, although they are a little rough in Cincy. As far as the higher RPM's go, they are fine. Although there is a spot on the powerband that it just likes to add some extra kick. Also the idle seems a little jumpy. After a rev in neutral, it likes to slightly drop down (200RPM), then come back up. I adjusted the idle screw higher to around 13-14 RPM, but it still isn't staying consistent. It is hard to start out from a dead stop. The bike doesn't seem to like to start going from 0 MPH smoothly. Very twitchy. Low speeds are manuevers are very hard because of this. Any ideas???
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Mine IS a carb'd 2002. I wonder if I just need it jetted or rejetted since there is a Yoshimura Slip-On on it from the previous owner. He said he never had it jetted.
Yup. Your jetting is off. It sounds like its lean popping. Fatten her up!
Go get some dyno tuning time. Very much worth every penny.
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It's not backfiring, afterfiring, or popping though. Still richen?Yup. Your jetting is off. It sounds like its lean popping. Fatten her up!
If it was backfiring, it would be too fat.It's not backfiring, afterfiring, or popping though. Still richen?
What happens is when you open up the exhaust, more air flows through the engine. If more air is flowing, then you need more fuel to keep the engine stoch. Mine was doing the same thing, until i put a PCIII (i have an 07) on it. No more jumping or weird power loss at RPMs.
I was searching the service manual and couldn't find how to adjust the air/fuel mixture. Also searched the forum and couldn't find a detailed writeup (prefer pics). Anybody help?
How do I richen my mixture? Do I just remove my airbox to get to it? Which screws and how much?
IMO, when it comes to something like tuning your carbs, if you don't know what you're doing or how to do, you shouldn't. I'm all for everyone learning to work on their own bike, but this is one of those things where if you don't have the right tools, you're only going to make it worse. I'd recommend getting it professionally tuned. (I think there's a place near Tr-County that does dyno tunes)
I think I'm close to a place called Pro Stock on Harrison Ave. They Dyno Tune for racing as well. I just got done running a few rounds of Seafoam in the gas tank only. Didn't really do much for it, but I have learned that the surging likes to happen when the bike is fully warmed up. Usually in 1st or 2nd gear around 8K RPM using only 25-30% throttle. When I'm idiling at light and I go to rev it, the RPM's drop lower than idle, like it wants to stall. The other day I was going through some twisties in second gear 8K RPM's and it was bucking so bad it died out on me. Since then I've replaced the fuel filter, and no different. I'm thinking it might be a carb and float problem.
Well, took it in and the pilot jet was dirty. They cleaned and synced the carbs, along with richening the mixture and tuning on a dyno. It runs a hell of a lot better! The only thing I notice now is that the bike gets hotter quicker when in stop and go traffic. They left the rubber mat (heat shield) off. They said they do that on everyone's bike. That might be the reason.
Thanks for letting us know what the problem is. I've synced the carbs my self like 3 times, and that helped but it still bucks a little at part thorttle. So I think I'll get a Ivans jet kit, put that on then clean and sync the carbs.
I talked to my service guys about the jet kits, and they've told me that a lot of Ivan's stuff is unnecessary. He is basically a really good salesman that has generated a lot of buzz. After I got my jets cleaned and properly adjusted, I can't see myself needing a jet kit. Clean, sync, and dyno tune was all that wass needed. Only cost me $275 also!Thanks for letting us know what the problem is. I've synced the carbs my self like 3 times, and that helped but it still bucks a little at part thorttle. So I think I'll get a Ivans jet kit, put that on then clean and sync the carbs.
How do you adjust a jet? As far as i know, its just a little replaceable screw that restricts the flow of gas. Tightening or loosening doesnt do anything, you have to replace the whole thing to adjust the jetting.They probably just swapped the jets out on your bike.I talked to my service guys about the jet kits, and they've told me that a lot of Ivan's stuff is unnecessary. He is basically a really good salesman that has generated a lot of buzz. After I got my jets cleaned and properly adjusted, I can't see myself needing a jet kit. Clean, sync, and dyno tune was all that wass needed. Only cost me $275 also!
They cleaned and adjusted the air/fuel mixture.
Thanks thats nice to know about the jet kit. I know that Ivan's kits are on the expensive side.I talked to my service guys about the jet kits, and they've told me that a lot of Ivan's stuff is unnecessary. He is basically a really good salesman that has generated a lot of buzz. After I got my jets cleaned and properly adjusted, I can't see myself needing a jet kit. Clean, sync, and dyno tune was all that wass needed. Only cost me $275 also!
You got a hell of a deal for $275:nocontrol, I went to one shop not long after I got my bike and they said it would be $400 for 5 hours work, and thats just to clean and sync carbs, thats why I try to do as much work as I can to my bike.
Now I just need to find a place in Oklahoma to dyno tune my bike I'll be set.
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