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Discussion Starter · #1 ·
Ah, my little R6 that keeps on giving... in problems. Found, or should I say felt a new one this morning.

Riding home from work this morning the bike was riding normal and everything felt fine at normal speeds, but at one point I went to accelerate to pass a slow moving car in front of me and I noticed that at high RPMS it felt like I was riding over small bumps/potholes. It was very rhythmic too, like every other beat it felt Like I was driving over a bump. Of course there wasn't any bumps in the road, it was something my bike was doing. The bumps didn't effect my handling at all, other than a quick moment of surprise since I wasn't expecting to feel it. The bike didn't feel like it was going to lose control or anything, and I was able to accelerate and decelerate fine, it just felt... bumpy?

Now it was very early in the morning (I work overnights so I leave work around 6ish). It was cold out (high 40's / low 50's), the road was wet and cold and my tires were cold so at first I just thought it was something to do with that, but later on when I started downshifting to slow down at a turn, I noticed it doing it at high RPMS will decelerating in 2nd. But then just a few moments later, I put it into 1st and accelerated all the way up to redline (albeit slowly, but still) and didn't feel it.

Not quite sure what it could be. Loose chain? I was inspecting my chain the other day and thought it looked kind of loose (it seemed like it had a lot of slack in it), but I've only owned the bike recently and haven't looked into chain specs or anything yet. Could it just be as simple as it being cold? Its certainly the coldest I've ridden the bike in so far, although I rode my old bike in cold weather and never experienced this. Slipping clutch? Tranny problems? It didn't feel like the bike was losing or surging power at all, like the acceleration felt normal, just with a rhythmic bump to it. Very weird.

Any and all help/suggestions are appreciated!
 

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2008 Yellow Flame R6R
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When’s the last time you checked your tire pressures, especially in the front?
 

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Discussion Starter · #3 ·
When’s the last time you checked your tire pressures, especially in the front?
Haven't yet, just got the bike about a month or 2 ago and haven't been able to ride it as much as I would've liked this summer and as a result have been lacking on checking up on its maintenance (which I really should get ontop of since I believe I have a coil going bad, something the previous owner said he had checked up on). I do know for a fact that the rear tire was changed last year and the front tire needs changing soon as its treads are low. I was going to ride it out for the rest of this season and change it either this year before putting it away for the winter or next year after taking it in the spring.
 

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Yeah you will feel something like your describing, quite possibly it’s your front tire. When I first got my bike the previous owner put on a new tire. One time I went for a ride a found the wheel weights had flew off. Later when I would accelerate at high speeds I would feel somewhat of a sensation like you mentioned. I neglected it for a few more months and after I broke my hand from a head shake, I found my front tire pressure to be at 28. Since the incident I check the pressure very often, especially if there has been a large swing in temperatures outside or if I haven’t rode it in awhile. So check the basics and get the tire replaced and balanced.
 

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Unlikely as you say its at high revs - but If the chain is loose (more than approx 45 mm slack) then adjust and check for a tight link that may be causing an issue especially on the the front sprocket
 

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Discussion Starter · #6 ·
Yeah you will feel something like your describing, quite possibly it’s your front tire. When I first got my bike the previous owner put on a new tire. One time I went for a ride a found the wheel weights had flew off. Later when I would accelerate at high speeds I would feel somewhat of a sensation like you mentioned. I neglected it for a few more months and after I broke my hand from a head shake, I found my front tire pressure to be at 28. Since the incident I check the pressure very often, especially if there has been a large swing in temperatures outside or if I haven’t rode it in awhile. So check the basics and get the tire replaced and balanced.
Thank you for the suggestion, ill check it out. It was warmer today so i took it for a quick ride and didnt feel anything unusual even at speed so im thinking it either had something to do with the cold or it was just a weird one-off event. Either way ill check out my pressures and check the tension on my chain while im at it.
 

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I would agree with the chain. I had an R1 awhile back that had 2 tight spots in the chain, and I would get about that same feeling when riding around. It was more prevalent since there were 2 spots, but definitely not normal. New chain and she rode happy again.

You mentioned it happened at higher RPM. Have you noticed the speed when you start to feel it? Try putting it in higher gears to hit the same ground speed? Just to check to see if the feeling is engine speed dependent or tire speed.
 

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Discussion Starter · #8 ·
I would agree with the chain. I had an R1 awhile back that had 2 tight spots in the chain, and I would get about that same feeling when riding around. It was more prevalent since there were 2 spots, but definitely not normal. New chain and she rode happy again.

You mentioned it happened at higher RPM. Have you noticed the speed when you start to feel it? Try putting it in higher gears to hit the same ground speed? Just to check to see if the feeling is engine speed dependent or tire speed.
I believe its engine speed dependent as i can cruise at like 70mph perfectly fine, but if i rapidly accelerate from say 50-70 then i feel it as im accelerating, but only if im accelerating hard. Like if i just gradually accelerate as if im driving normally then it feels fine, but if i pin the throttle and accelerate rapidly i start to feel it after id say 10k rpm. Also, to be more specific, it feels like its coming from the rear of the bike.

I havent had time to take a look at the bike in the past couple days due to work but hopefully i can soon. Im hoping that its something as simple as a chain or as a new tire as someone else suggested
 

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Discussion Starter · #9 ·
Unlikely as you say its at high revs - but If the chain is loose (more than approx 45 mm slack) then adjust and check for a tight link that may be causing an issue especially on the the front sprocket
Will check. No idea when the chain was last changed or even tended to so ill check up on it. I saw a gixxer forum post about someone with a similar issue and it ended up being bad gears. Crossing my fingers that i dont have the same issue, although i feel like if i had some messed up gears id feel it throughout the rev range and not just up top.
 
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