Author Topic: Tranny issue (Read 8220 times) Tweet

tfracing · « **on:** July 13, 2003, 08:08:00 AM »

Bike won't shift between 3 and 4 while racing. Have to hit to shift button mutliple times. Replaced the drum and forks two weeks ago. The tranny was done last winter.
If I need to replace the gears which gears would be needed?

SJJBusa · « **Reply #1 on:** July 13, 2003, 10:50:00 AM »

If the trans is undercut, you need to send the drum to R&D for their NOS drum mod. Problem is the forks flexing/binding because the slots in the drum do not allow the forks to slide far enough to allow full gear engagement.

SJJBusa

tfracing · « **Reply #2 on:** July 13, 2003, 11:02:00 PM »

Thanks...
Opens room for questions. I have several buddies running stock trannys and they never have issues. Why would mine fail if it's cut?
Why just 3 to 4 shift?
Installed new forks, drum and billet shaft. Still no shift 3-4...
Want to take the next couple weeks off so I'm going to "disassemble #5" and have the work done or parts replaced. Just need the most probable fix.

Hey, I'll spend the money if it will fix the problem.
TFR

SJJBusa · « **Reply #3 on:** July 13, 2003, 11:34:00 PM »

On a non undercut trans, the gears final depth of engagement is controlled by the forks, which are controlled by the slot in the drum for the fork in question. (3 & 4 use the same fork/slot). However, on an undercut transmission, once the gears start to engage, they will attempt to pull themselves into 100% engagement depth. If the slot in the drum does not allow this to happen, the weak link is the fork, which will flex & bind, thus requiring multiple presses on the air shifter button to get it to first unflex, disengage, and then re-engage the next gear. In extreme cases, the forks and or shafts will be permanently bent. If you have any more questions on this topic, please use the search function, this topic has been covered on a few different occasions. R&D's mod to the drum is just a clearancing of the final engagement position of the slots, to allow the forks to come closer to the gears.

SJJBusa

DaveO · « **Reply #4 on:** July 13, 2003, 07:22:00 PM »

Been there, done that. Send it to R&D for the NOS mod as SJJ said. Wouldn't shift 4-5 either. Have them check your shafts too, mine was out ~.010

Dave

Holeshott · « **Reply #5 on:** July 14, 2003, 03:45:00 PM »

hi guys
I know i dont post much but work gets in the way. Im also having this problem with my bike. I have an 02 with a je 1397 kit. last year it shifted flawless, now after about 20 passes it wont shift. Ive even tried foot shifting it and nothing nada im crossing the line on the limiter. Now here's whats really got me ! I split the dam cases and nothing THE TRANS LOOKS BRAND NEW!! Like the day suzuki put it in!! So now im putting in new forks and billet shafts, but im not quite sure this is gonna fix it. any ideas?? By the way ive done all the usual checks bled the clutch again, new fibers and steels, and new springs. Help please this one has me stumped.

thnaks all
tony
p.s. could the mps kill box have anything to do with this??

King bu · « **Reply #6 on:** July 14, 2003, 04:10:00 PM »

If your clutch is slipping it will not shift in the upper gears. Do you have a lockup for your 1397?

stockbusaNOS · « **Reply #7 on:** July 14, 2003, 06:11:00 PM »

you need the solid shift shafts,shift fork
and the drum from r/d is only for 5th gear

SJJBusa · « **Reply #8 on:** July 14, 2003, 06:40:00 PM »

quote:
and the drum from r/d is only for 5th gear

That's news to me. When I spoke to Mark before sending my drum & trans there, he said they do all three slots, and they did

SJJBusa

Holeshott · « **Reply #9 on:** July 14, 2003, 08:05:00 PM »

First id like to say sorry to sjjbusa for stepping on your post. This problem is killing me and your the first one ive heard have this problem, and would like to get it sorted out.

No king bu no lockup yet(to many bills right now) but there is one in the VERY near future. Right now im running the brock lever adjuster and clutch spring setup. I removed the cusion and added 1 more thick fiber.

I do agree about the clutch slipping/no gear change combo, but what about 2nd to 3rd. if 3rd to 4th is slipping bad and wont let it shift, why wont it do it from the 2/3 shift? not bashing just trying to learn.
thanks again
T

tfracing · « **Reply #10 on:** July 14, 2003, 08:36:00 PM »

I'm not sure who this will help in this post but here I go...

First I posted to try to figure out why mine won't shift from 3 to 4 on a drag pass. It shifts fine during a ride but not under WOT.
One guy posted about having the drum modded and so I called to discuss this with Mark.
Mark said that they only cut the drum for 4 to 5 and 5 to 6. The other gears don't require the "drum mod". He said that if I changed the drum and have good forks and billet shafts it has to be the gears. Pretty much knew that but waqnted to hear it from him.

Now, there are many things I found that will cause the tranny to not shift under WOT.
1. loose chain
2. Kill wire detached from one of the coil sticks. Make sure they all show good continuity from the MPS box to the coil.
3. Worn gears
4. Bent shafts and or forks
5. worn drum
6. Not enough kill time. Every one thinks they can shorten the kill time to help ET. Well that works but also hurts the tranny.

Mine is probably a poor undercut job. Now I'll send it to the man...

Holeshott · « **Reply #11 on:** July 14, 2003, 08:44:00 PM »

man I meant to say sorry to you tfr.
thanks for the info.
I soldered my conections to the mps box so that connection im not so worried about, but what boout the box itself? could it be bad? is there any other companies besides mps I could try? or just swap out for a new box?
I know so many questions, but yet so much time

I just wsord that my motor wont be home for yet another week

thanks again
T

tfracing · « **Reply #12 on:** July 15, 2003, 01:46:00 PM »

I have a NLR box. So far so good with it...
Similar wiring hookup. Little better kill adjustment.

cstraubs1 · « **Reply #13 on:** July 15, 2003, 04:54:00 PM »

TFR what killtime u runnin'?? And who did the previous work on the tranny?

tfracing · « **Reply #14 on:** July 15, 2003, 07:35:00 PM »

I've run from 50ms to 90ms and I don't want to disclose the tranny cutter. Let's say it was a very reputable shop.

Chuck · « **Reply #15 on:** July 15, 2003, 10:26:00 PM »

If you get that tranny to R&D, your problems are over. Mark is an absolute genius/perfectionist when it comes to motorcycle trannys. He built the tranny in my TG Busa. I put over 100 passes on it last year without 1 missed shift. Over the winter I pulled it out, sent it down to him for a check-up and have put 55 passes on it this year so far without a single missed shift.

tfracing · « **Reply #16 on:** July 16, 2003, 02:15:00 PM »

Mark, has done all my tranny work until this time. He was too busy at the time.
Now he has it anyway...

fastby busa · « **Reply #17 on:** July 25, 2003, 08:36:00 PM »

WHATS R AND Ds WEB ADRESS OR PHONE # THANKS

SJJBusa · « **Reply #18 on:** July 25, 2003, 08:39:00 PM »

R&D's phone # is 727-447-4552

SJJBusa

juice · « **Reply #19 on:** July 26, 2003, 11:09:00 PM »

How long are yourlines? Mine where about 18" and then I moved the acuatorwithin 4" and that helped. I also had mine done by RnD. Had everything done to it. Works great now. Every shift!

tfracing · « **Reply #20 on:** July 26, 2003, 09:55:00 PM »

Just got my tranny back from R&D. Looks great.

Mark and I talked for a few minutes about the trany and what he found. He said the tranny wasn't cut properly and that he repaired it. He also did a clip mod on it. Not sure what that intails but will look to see tomorrow.

He is the man...

Commuta_Busa · « **Reply #21 on:** August 15, 2003, 09:20:00 AM »

just curious... where is this R&D shop located? Sounds like they may be my new source in regards to trans work....

News:

Author Topic: Tranny issue (Read 8220 times) Tweet