6 speed in GPz 750 questions

I have a 6 speed from a GPz550. I am putting it into my GPz750. (I read about this on a GPz site.)
I have cracked the cases and examined the gear shafts. I have slipped the 6 speed output shaft into the case. It appears to be an exact fit, which pleasantly suprised me.
My questions:
Has anyone else done this or seen it done?
Are there any things I need to be aware of?
It appears that the sprocket will have the same alignment with the rear sprocket as the 5 speed I am removing. Is this correct?
I have noticed that at least 2 of the gears are not as wide as the 5 speed. Will I have any problems with the power of the 750, which will have a Wiseco 810 kit, shaved head, K&N pods, and a V&H 4-1 header?
Thanks in advance, kk

i dont know anything about this. so i might be wrong. but it seems that the gears on the 6speed wont be as wide b/c theres 1 more gear than the 5 speed

Post edited by: rollingstock, at: 2005/10/24 22:08

Hi koolaid_kid.
I can't answer your questions, but I AM looking forward to your results. I have a 2001 ZR-7S (GPZ750-type engine) and heard that I could replace my 5-speed tranny with that of a GPZ550.
Good luck, and keep us posted on the outcome.
Jim

I suggest you do a search here in the "archive" section. I vaguely remember this being discussed long ago. If I recall correctly, as compared to the 5 speed transmission, the 6 speed from the 550 does not add any to the overall gear range, top to bottom. Instead, it narrows the range of the gearing in the middle gears, and adds an additional middle gear. So, for example, if you are trying to maintain great first gear acceleration, and have less "buzz" when you are crusing on the highway in the top gear, this swap will not do that. It will give you a larger choice of gears to use when zipping through the curves on the road course.

Thanks, apeman. I checked the archives, someone named Mark Bell was not successful in putting a 6 speed into a 650, apparently due to the kickstarter issue.

I did check the gear ratios, they are as follows:
550
1st 2.57
2nd 1.78
3rd 1.38
4th 1.13
5th 0.96
6th 0.85

750
1st 2.33
2nd 1.63
3rd 1.27
4th 1.04
5th 0.88

It has a lower first gear, kind of mixed in the middle gears, and a slightly higher 6th gear. The overall spread is wider, but geared to the lesser power of a 550.
Since the bike will primarily a canyon carver, this is ideal for me. When chain replacement time comes, I will probably play with the sprocket ratios a bit to make it more ideal for the added power of a 750.

That's the post I was talking about. The good news is that you probably can do this, since the GPZ does not have a kickstarter to worry about, right? Also, contrary to my missinformation, you will get at least a slightly greater range of gearing. Let us know how this works for you. If it is not too hard, I may consider this for one of my bikes. This would be especially flexible if I swap the 630 chain and sprockets for 530's.

Correct, the GPz has no kickstarter, just as your 750E. I am sure that something will come up; it always does.
I will have to wait until it is running to determine what to do about the slightly wider spread and lower first gear; I really do not want nor need a wheelie machine.
I would love to move to a 530 set when I change the chain, but I have been told that the offset of the countershaft sprocket is a problem with the 750 engines (at least on my GPz). Would you know of a solution to this issue?

Maybe as soon as I get my lathe and mill installed we'll have a solution
But that will be next spring when I build an addition onto my garage

steell wrote:

Maybe as soon as I get my lathe and mill installed we'll have a solution
But that will be next spring when I build an addition onto my garage

Woohoo!! :laugh:
I mean, dang!! :blink:
That's O.K., the GPz will take that long to get going.
I hope to have an initial answer to the forum by this time next week. I will fit both shafts, forks, and drum and check it out on the bench. Since the kickstarter is a non-issue, I feel pretty good about my chances.

I will also be posting a related issue over in the bodywork forum...

Sprocket availability for the GPz550's are 15, 16, and 17 front, and 38, 42 for the rear.

I can e-mail you a gear chart you can play with for your sprocket choice. I can't post a link here.

Post edited by: CoreyClough, at: 2005/10/25 21:57

got it.

thanks, kk

Post edited by: koolaid_kid, at: 2005/10/26 17:55

koolaid_kid wrote:

Since the bike will primarily a canyon carver, this is ideal for me.

Man!
You're gonna have to tell me where you ride in Indiana!