BA
Pro
Posts: 1592
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posted May 09, 2002 09:24 PM
I have a Tranny / Shifting question......
Had a decent night at the track tonight......even though it was humid from raining all week, and about a 7-18mph headwind.
Ran a 9.45 and 9.40, both at exactly 147.06. (odd, eh?)
I find that I'm still missing 3rd gear sometimes though (!) and it's bugging the HELL out of me! I'm certain my chain is adjusted correctly, and a friend rode it down the track, and HE missed 3rd gear too! (neither of us use the clutch from 2nd-4th when drag racing.)
At the end of last year, when I had my best runs ever(those 9.3x's), I hadn't missed a shift in about 2 months. I had been zeroing in that shift lever adjustment for quite a while, and had finally gotten it to a 'sweet spot'.
A friend thought that my tranny might be out of adjustment, or messed up somehow. ie...shift forks or something.
I've never had a bike tranny apart, so I don't know shite from shinola.
I need advice! What do you guys think? Is it possible that a 7500 mile 12R, using synth. oil, and frequent oil changes would have a tranny problem or need adjustment?
PS. I race once a week, and get about 4-6 runs in.
Last year, we ended around early - mid November. This year, we just started up about 3-4 weeks ago.
Thanks for the advice!!
  
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ZRXDean
Needs a job
Posts: 2225
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posted May 09, 2002 11:29 PM
I had a similar problem, I would guess it's possible. In your exploits at the track, have you missed a fair number of shifts? As a result of repeated missed shifts, the shift forks and/or engagement dogs will become bent/rounded, and it will be more and more difficult to get smoothly into gear, thus leading to more missed shifts, and more abused parts, until you are so pissed off you can't see straight. An airshifter might make the problem disappear - although it would be easy to take a peak under the oil pan.
You're smokin' BA. What are your 60 foot times (stock-wheelbase right?) ?
Dean
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MadMike
Moderator
FEAR THE BLACK FLAG!!!!!!!!
Posts: 6579
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posted May 10, 2002 04:03 AM
I have had my motor apart 2 times and man those transmissions are built like a brick shit house.. Im sure something can happen.. but it will be easy to check and hard to fix... just drop your oilpan like Dean said and then you can see all of the transmission... and the dogs are right there so if they are bent or something you will be able to tell...
Mad Mike..
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Cowboy
Pro
Posts: 1061
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posted May 10, 2002 05:43 AM
I don't know if the air shifter will take it away because I have the muzy airshifter which i thought was bolt on and go and i'm missing shifts all the time.Doesn't seem to miss as many when i have less kill time but still misses at least once every time down the track.Going to try it again this weekend and then call muzzy if i can't get it to be reliable.
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RAC4IT
Needs a job
Bergie
Posts: 3009
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posted May 10, 2002 09:30 AM
quote:
I don't know if the air shifter will take it away because I have the muzy airshifter which i thought was bolt on and go and i'm missing shifts all the time.Doesn't seem to miss as many when i have less kill time but still misses at least once every time down the track.Going to try it again this weekend and then call muzzy if i can't get it to be reliable.
Did you add the shim that was supposed to fix this problem, it increases pressure. Muzzys sent out shims that you need to put in the regulator under the existing spring to add more pressure.
Also for those foot shifting and still having problems, try preloading the foot shiftlever some; twice even (lift up/release/liftup again before shifting).
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BA
Pro
Posts: 1592
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posted May 10, 2002 09:47 AM
Hey, that's good info guys. Thanks.
I'm kind of wary though, I mean, I can take off the pan, but how will I know if the 'fork' thing is "just ever so slightly bent"? Would it really be that noticeable? I was thinking it would have to be mic'd or measured or something. (put on flat surface, like glass or something?)
It's probably safe to say that I've missed a "fair" number of shifts, seeings as I race every week, and it's my street bike so my chain has periods of getting too loose.
Dean, thanks man. I think I can run consistent 9.35 - 9.42@149-150mph, but I'm still getting the cobwebs off for this new year.
You're right, the wheelbase is stock. My 60' times are usually 1.55 - 1.59 with 1.57 really being the common spot.
Last night I had what might be my best ever, it's a 1.529!
The launch style was different for me though, but I need to try to duplicate it consistently. I didn't slip the clutch as much, and was probably WOT at about 25-40' out. The engine gave a little bit of that "bog" sound as I was under-rpm'd but it also keep the wheelie factor down. (??) go figure. The bog, if you can call it that, actually seemed to help.
Put that same bog sound on a 9R or 6R and I would have lost 2 tenths in the quarter, easily.
So, back to the fork things, is it really that visible?
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ra12r
Zone Head
Posts: 919
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posted May 10, 2002 10:49 AM
Reverse your shift pattern. That will help i do strongly believe.
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BA
Pro
Posts: 1592
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posted May 10, 2002 11:21 AM
Shift pattern
Reversing would probably help, I agree, but I would still be intensely curious as to WHY this is happening, when I had two solid months of perfect shifts at the end of last year. Ya know?
Might be worth a try for a week or two though......
I'm still going to buy new springs anyway. 
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ZRXDean
Needs a job
Posts: 2225
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posted May 10, 2002 11:53 AM
Dude, 1.52 with the stock arm is excellent - you should race the 600s in Prostar, I bet you could make top 5 no sweat. I'm psyched with mid 1.50s (best 1.53), with 6" extra and a shootout tire. I know what you mean about the 'bog' - if I hit it just right I can pull myself out of the hole from mid-rpm, with no wheelies, and a fast time. Hard for me to duplicate though.
About the shift fork - you're right, you really need to remove it to judge if it's bent. I don't know how difficult it is to pull the shift drum on the 12, but I imagine it's pretty simple if you have a manual and a clean workspace. There is nothing worse than missing shifts - especially when you know you had a good launch, and your hitting your shiftpoints, then CLUNK, rev, chit, the run's over. Good luck.
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madmike
Moderator
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posted May 10, 2002 02:20 PM
From the way mine looks you have to split the cases to remove the forks, I will double check this weekend and let you know...
Mike
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BA
Pro
Posts: 1592
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posted May 10, 2002 02:59 PM
 Edited By: BA on 10 May 2002 16:01
Thanks Mike and Dean. Mike, buddy, I'll owe ya one if you get me a confirmation about what's involved with that....
You guys are being a big help. I appreciate it. It's also good to hear that someone else has experienced this mid-rpm bog that results in good 60's and 330's. That makes me "not as much" of a freak! hehe
Dean, I've come close to racing 600SS for the past 2 yrs, but things haven't really made it as easy as I'd like. I have kinda hoped/thought that I *could* make the top 10 anyway, so, thanks for the compliment.  Maybe 2003.
Who knows, one day you might see a big BA RACING on a bike or trailer, or maybe TEAM BDE/BA........
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Cowboy
Pro
Posts: 1061
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posted May 10, 2002 08:58 PM
quote:
quote:
I don't know if the air shifter will take it away because I have the muzy airshifter which i thought was bolt on and go and i'm missing shifts all the time.Doesn't seem to miss as many when i have less kill time but still misses at least once every time down the track.Going to try it again this weekend and then call muzzy if i can't get it to be reliable.
Did you add the shim that was supposed to fix this problem, it increases pressure. Muzzys sent out shims that you need to put in the regulator under the existing spring to add more pressure.
Also for those foot shifting and still having problems, try preloading the foot shiftlever some; twice even (lift up/release/liftup again before shifting).
I just bought mine a week ago.Do you think i still need the shim?It was not sent with the kit.
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krexken
Zone Head
Posts: 732
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posted May 10, 2002 09:28 PM
Anyone that can get wide open that quick in first gear with a stock wheelbased 12 is a bonafide freak in my book! Heck, wide open in frist gear at all! You're flat riding the snot outta that thing.
Good luck on the tranny.
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kcadby
Pro
Posts: 1733
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posted May 13, 2002 09:20 AM
BA you need to make sure your clutch is NOT slipping AT ALL...
Dean is right...after "too many missed shifts" the tranny does wear...the forks can get burnt and/or bent and the "dogs" on the gears get rounded off...
Once this happens???there is NOTHING to do but tear it dowm and repair the damage...
The GOOD news is...you have to damage the gears pretty bad before an "undercut" won't be good enough to repair the gear
As stated above...you should be able to see the gears good enough from below (pan off) to see if the "power side edges of the dogs" are rounded off or not...
GET A KILL BOX and hook it to your horn button!!!
I NEVER MISSED A SHIFT using the ignition kill and my foot to shift!!!
Get a shift light...when the light comes on...PUSH the shifter (GP shift patern) then the horn button...NEVER MISSED A SHIFT LIKE THIS!!!
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