Author Topic: Slipping Gear (Read 6956 times)

Vidrazor · « **on:** September 14, 2007, 11:35:54 AM »

My second gear is slipping once I get up ~6-8k. The guy at my shop says it would require more work than the bike's worth to fix, and that I should just "short shift" second. I usually skip shift to third instead. What exactly causes this? Thanks.

Red01 · « **Reply #1 on:** September 14, 2007, 11:43:45 AM »

You sure it's the gear that's slipping?
Clutches slip. Gears don't "slip" unless teeth aren't engaging... and that usually comes with a lot of noise.
M/C gearboxes will jump out of gear from bent shift forks or damaged dogs, but this sort of repair shouldn't cost more than the bike is wort unless it is a real beater of a rat bike.

interfuse · « **Reply #2 on:** September 14, 2007, 12:23:52 PM »

Start by adjusting the clutch as per the manual. I'd bet it'll fix the problem.

yuckhil · « **Reply #3 on:** September 15, 2007, 10:52:58 PM »

G'day all,
I'm not sure, but I may have a similar problem. When shifting up into second at 4,000+ rpm, I feel/hear gears crunching and feedback in the gear lever. This is while raising the gear lever with the clutch level fully in, not while releasing the clutch.
Since the first couple times, I've been short-shifting for several weeks now, except when I forget or my blood is up. She's due for the 18,000 service and the mechanic told me that clutch adjustment is included in the service and should fix the problem. That make sense?
Thanks.

Red01 · « **Reply #4 on:** September 16, 2007, 11:37:29 PM »

I'd think an out-of-adjustment clutch would be that way all the time, not just ~4K rpm...

interfuse · « **Reply #5 on:** September 16, 2007, 11:53:24 PM »

I'm not sure where 4k came from, but when my clutch was misadjusted i'd get slipping around 8k... thats when the 400 actually starts making power (I'd assume that under 8k the bike wasn't making enough power to slip the clutch???). It may not fix the problem, but start with the cheap stuff.

yuckhil · « **Reply #6 on:** September 17, 2007, 12:55:16 AM »

Thanks guys.
I meant anywhere over 4,000 rpm. Above 4,000 rpm it's just a slight feedback in the gear lever. If I change much higher, maybe over 8,000 rpm, then I hear and feel distinctive crunching. Ow. Even if I've rolled off the throttle.
Oh yes, I also had my first puncture yesterday. Bloody home renovation loons leave wood chips all over the apartment block!

CheerS!

EDIT: Hahaha, apologies for turning this thread into my issue!

Vidrazor · « **Reply #7 on:** September 17, 2007, 05:17:11 PM »

Yeah, dunno. I think if it was a simple clutch adjustment, the shop would do it instead of saying it ain't worth a tear-it-apart-and-repair job. The bike's got 33k on it, and I don't know if the previous owner raced it or not, a possibility.

The bike's generally been good except for clogged carbs from a rusted tank. Replaced the tank and had the carbs cleaned and it's been good (although recently it's been acting up again, stalling at low revs and turning over a lot if I stall it on takeoff).

So I'm not really sure where the 'ol bugger stands.

gsxr400 racer · « **Reply #8 on:** September 26, 2007, 12:02:28 PM »

Quote from: "Vidrazor"

Yeah, dunno. I think if it was a simple clutch adjustment, the shop would do it instead of saying it ain't worth a tear-it-apart-and-repair job. The bike's got 33k on it, and I don't know if the previous owner raced it or not, a possibility.

The bike's generally been good except for clogged carbs from a rusted tank. Replaced the tank and had the carbs cleaned and it's been good (although recently it's been acting up again, stalling at low revs and turning over a lot if I stall it on takeoff).

So I'm not really sure where the 'ol bugger stands.

change the clutch pack and go from there , sounds like a bad chain to me and if you don't have a fuel filter on it really doesn't matter that you changed tanks as all the bandit and many Suzuki tanks suffer from this rustiness only true way to fix is to kreem the tank.

Vidrazor · « **Reply #9 on:** September 27, 2007, 02:51:45 PM »

[[change the clutch pack and go from there]]

Why would the clutch only slip on 2?

[[sounds like a bad chain to me]]

Drive chain? Had new chain and sprockets put in some K's back (somewhere between 5 and 10k, methinks). Don't think I've run the shit out of 'em yet.

[[if you don't have a fuel filter on it really doesn't matter]]

No way I'd go without one after I replaced the tank, maybe it needs replacement. The tank's still clean. It's been giving me a hard time starting up for the first time of the day lately. If I should stall after running for a while, it intermittently can just spin 'round n 'round off the starter for a while, have to sit a few moments, and then finally decides to start.

Thief400 · « **Reply #10 on:** September 29, 2007, 10:47:03 AM »

If it is truely the clutch The problem would get worse not better in the higher gears. Sounds like you bent a shift fork which is common, and usually it's a miss adjusted clutch and trying to shift to fast that causes that to happen

yuckhil · « **Reply #11 on:** October 04, 2007, 06:29:05 AM »

Hello all!
Apologies again for squeezing my issue into this thread. Looks like it is not related to Vidrazor's issue.
Well, I got her back from the 18,000 service, silky smooth and all that, but even though they promised to look into it, the problem still exists.
Once I get above 4,000 RPM, the 1-2 shift is very uncomfortable. This gets worse the higher I shift 1-2 and is especially apparent when shifting 1-2 on a steep climb. Seems to me like the load. i.e up-slope, hard acceleration, etc. contributes to the problem. None of the other shifts are affected.
So I might take her back to the workshop this weekend, but I was hoping for some words of wisdom to go armed with! Thanks!
CheerS!

gsxr400 racer · « **Reply #12 on:** October 04, 2007, 10:13:26 AM »

Quote from: "yuckhil"

Hello all!
Apologies again for squeezing my issue into this thread. Looks like it is not related to Vidrazor's issue.
Well, I got her back from the 18,000 service, silky smooth and all that, but even though they promised to look into it, the problem still exists.
Once I get above 4,000 RPM, the 1-2 shift is very uncomfortable. This gets worse the higher I shift 1-2 and is especially apparent when shifting 1-2 on a steep climb. Seems to me like the load. i.e up-slope, hard acceleration, etc. contributes to the problem. None of the other shifts are affected.
So I might take her back to the workshop this weekend, but I was hoping for some words of wisdom to go armed with! Thanks!
CheerS!

sounds like bent shift fork or bad gear

Vidrazor · « **Reply #13 on:** October 05, 2007, 12:18:50 PM »

Interesting. I also get a grinding gear sound in first/second, but only when I'm coasting in neutral and I try to shift back into gear. If I'm over a certain speed, the gears grind and bitch to to all hell and give me the hardest time trying to finally fall in.

If I'm under a certain speed (I don't really know what the threshold speed actually is) the gear just drops in like normal, no drama.

If I'm at a complete halt, it's sometimes impossible to change gears (from or to first). The shifter is solidly locked. I have to throttle the bike a few inches in gear and then it switches like normal.

Are these all indicators of a bent shift fork? If so, is this a major project to correct?

pmackie · « **Reply #14 on:** October 05, 2007, 12:31:50 PM »

Hey Vidrazor

Quote

Are these all indicators of a bent shift fork? If so, is this a major project to correct?

No...this sounds pretty normal for the sliding dog type transmissions on motorcycles. Wear in the shift drum can make the shift to and from Nuetral, 1st & 2nd worse over time.

Going from Nuetral to 1st or 2nd while coasting is always going to be noisy, since your trying to force the dogs together while their speeds are different. You would need to "match" the correct engine rpm to the road speed in that gear to have a smooth shift.

However, if the transmission is "jumping" in and out of 2nd gear after you shifted, you either have a bent shift fork or damage to the dogs on the gears. This can be caused by or made worse by forcing the tranny into gear as you have described.

Generally, the tranny does not need to be "forced" to change gears, it should snick into the next gear without a lot of drama or noise.

Maybe you can descibe your "slipping" problem at high revs again?
a) if the clutch is "slipping", the revs will rise slowly without an increase in road speed, just like if you start pulling in the clutch lever while riding. Usually this is worse in higher gears, or when climbing hills.
b) if the transmission is acting up, you may get a jerky ride as if it is "jumping" out of gear, or if the shift fails, you will get a "missed" shift with the revs going to the moon, and you have to shift again.