Road experience:

[WWJD]

My paranoia all started with some guy posting something about a lawsuit for SUZ to fix some weird "Neutral Glitch" in his tranny - he was gathering info about people who's bike popped out and back in to gear under high stress conditions. I've never had that problem but everything I read here stays lodged in my cranium for later access as needed.

Here's the deal: over the past 4 weeks or so I've noticed a potentially weird thing occur. Or at least I THINK I noticed something odd.

What caught my eye and ear is while WOT in 1st, 2nd or 3rd, once or twice a ride, I would hear, feel and see the RPMS drop DOWN 1000 or so, somewhere tween the 7 - 10k range, just for a second.

I am familiar with what happens when you are literlly flying over bumps: rear lifts enough, or is in the air and the revs rise quickly... you land and the bike lurches forward faster due to the power and spinning tire, and you SEE the rpms spike UP for a second... but what I experienced above was sort of the opposite - like the engine cuts, revs drop, bike slows and then kicks in again. And it never seems to happen with anything less than FULLY PEGGED, wide open throttle, which I do a lot of in 1st - 4th gears when conditions permit.

Actually now that I type this all out, it does seem that something is up. It feels like I let off throttle for a sec, but that is not the case. And it is not a bump causing me to lay off the throttle, cuz I don't allow that. I'm used to the unstoppable rocketsled feel even with a bump in the road. Also, I think I noticed the droppage because they happened in flat spots - If it was launching over a bump I doubt I'd think twice about bike reactions.

Any input?

I forgot to mention it's an 03 Busa with about 27k miles on it [well maintenanced], seems to only happen above 6-7k, when riding like that I am shifting around 10 - 11k - but it happens BEFORE the rev limiter - I know the limiter well and am used to IT



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[justintime2]

WWJD,
This sounds exactly like the the problem the other guy was having and the same one I had. It feels like the bike lurches by dropping a 1000rpm and then coming back on. Creats kind of a jumping feeling.

It happens under WOT usually around 7k RPM or higher but will start to happen at lower and lower RPM's as time goes by and it gets worse. I had to have the transmission replace in mine for this reason and it turned out to be worn gear and shift fork. Shift fork could be bent too. An expensive fix so PM me for some tips if you end up needing it done and it turns out to be this problem. And it sure sounds like it is.

 

[JINKSTER]

"What caught my eye and ear is while WOT in 1st, 2nd or 3rd, once or twice a ride, I would hear, feel and see the RPMS drop DOWN 1000 or so, somewhere tween the 7 - 10k range,"

damn....that's exactly what I feel when my rear tire finally hooks up.

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[Charlesbusa]

Could be clutch also, how old is your clutch? My problem was very similiar. Hard to tell if I was spinning the rear, clutch going out or problem with tranny.

I had 31k miles on my stock clutch, went to my first trackday, and now I have replaced it at 33k miles.

I wanted to give it some break-in time, as advised by others, I have yet to see if the problem is cured.

 

[WWJD]

Interesting. JT, I'm hoping it lasts until I can trade for an 07, if it's "all that"

I might PM you soon on this.

Jinx, I dont hear or feel any spinnin... I know how that sounds/feels. This seems like the limiter is kickign in for a sec much lower... or something

Charles, stock clutch, 27k miles or so on it. about 6 track days, plenty of "spirited" riding. I shift clutchless a lot too, but am pretty smooth about it, cept on the track. I'll have them check it when I take it in

 

[Charlesbusa]

When I did my clutch the fiber discs still had meat on them. The springs must have gotten weak.

But I still have to test it out before I know that the problem is fixed.

 

[The Big Red One]

My paranoia all started with some guy posting something about a lawsuit for SUZ to fix some weird "Neutral Glitch" in his tranny - he was gathering info about people who's bike popped out and back in to gear under high stress conditions.  I've never had that problem but everything I read here stays lodged in my cranium for later access as needed.

Here's the deal:  over the past 4 weeks or so I've noticed a potentially weird thing occur.  Or at least I THINK I noticed something odd.

What caught my eye and ear is while WOT in 1st, 2nd or 3rd, once or twice a ride, I would hear, feel and see the RPMS  drop DOWN 1000 or so, somewhere tween the 7 - 10k range, just for a second.

I am familiar with what happens when you are literlly flying over  bumps:  rear lifts enough, or is in the air and the revs rise quickly... you land and the bike lurches forward faster due to the power and spinning tire, and you SEE the rpms spike UP for a second...  but what I experienced above was sort of the opposite - like the engine cuts, revs drop, bike slows and then kicks in again.  And it never seems to happen with anything less than FULLY PEGGED, wide open throttle, which I do a lot of in 1st - 4th gears when conditions permit.

Actually now that I type this all out, it does seem that something is up.  It feels like I let off throttle for a sec, but that is not the case.  And it is not a bump causing me to lay off the throttle, cuz I don't allow that.  I'm used to the unstoppable rocketsled feel even with a bump in the road.  Also, I think I noticed the droppage because they happened in flat spots - If it was launching over a bump I doubt I'd think twice about bike reactions.

Any input?

I forgot to mention it's an 03 Busa with about 27k miles on it [well maintenanced], seems to only happen above 6-7k, when riding like that I am shifting around 10 - 11k - but it happens BEFORE the rev limiter - I know the limiter well and am used to IT  

Wd you'd know if you had a tranny prob...they're very unmistakable. And it only happens in the bad gear...not all of 'em. And the rpms will jump up and down very radically, but never just down. Same with a clutch, chain or sprocket prob...you get a jump up in rpms...not down. Since you said you don't have any spike in rpms before the drop, it sounds like your losing power for a sec. A plug change might not hurt if its been awhile...and maybe a new fuel filter as well if you have the older style fuel pump set-up. Or you could possibly be developing an injection prob of some kind. Hope this helps

 

[WWJD]

more good info. thanks. I did wonder why it only seem to happen under higher revs and hard pulling conditions, more i think about it, it seems like power cuts rather than mechanical. I look forward to taking her out and making lots of high speed test runs... in teh name of science and diagnostics, of course

 

[Charlesbusa]

Just finished testing the new clutch kit, all good!!!!

No slipping at all

Also, your rpms may seem to drop, but you might not have noticed them spool up. Then when they settled back down and stopped slipping, you notice the drop.

Just a possiblitity.

 

[riironman]

sounds like my bike...I am waiting for a used fuel pump now. I have trouble after 7000 RPM. I changed the plugs and the clutch. So I am thinking under load Its not getting enough fuel. After that I am Lost. Today i was riding with 3 ZX-10's anf My brother Gsxr 1000....I hated not being able to keep up.