78 KZ750 w/ 03 Gsx-r Swingarm, Monoshock mounting questions (Pics)

Hello, I have been cruising silently around this forum for about 6 or 7 months.
Like my subject says, I have a 78 kz750. I am swapping in, the front and rear suspension off a 03 Gsx-r with 04 hyabusha wheels.
I have the front end mounted fine, but I am struggling with mounting the monoshock.

Here is where I am at now. I have the swingarm mounted. I made up adapters to use the KZ swingarm bolt in the Gsx swingarm. I made up some pieces to mount the lower shock mount. I am stuck here.

I dont know what angle for the lower shock mount is correct. I have searched the site and dont see anything addressing this. I found a few pics from different setups. I am not very familiar with the workings of a monoshock setup.

I do realize that under no rider weight, the swingarm will be at more of a angle. I just used whatever I had to hold the swing arm off the frame.

Does this look right?
Does the angle look right?
Does the spacing look right?
I do realize that under no rider weight, the swingarm will be at more of a angle. I just used whatever I had to hold the swing arm off the frame.






Post edited by: Jornum1, at: 2006/03/26 10:56

Post edited by: steell, at: 2006/10/19 18:15

Wow. I am absolutely jazzed about your bike.

Unfortunately, I don't have any scientific answers for you about the monoshock, but I do think it looks right. Actually, it looks awesome....

Also, I have a question: did the fork/tree go on without modification? You have the wheels spinning in my head....

It looks good to me but I wouldn't know if it was mounted upside down either, but do you know anyone with a gixxer? maybe get some measurements / angles off a bike that has that suspension originally.
Let us know how it works out , the wheels in my head are starting to turn also.

Grrrr.
Don't you know it's silly and a waste of time to do that to a 750 twin! Much better to spend your time and efforts on a 1000!!

Besides that, you are making my bike look bad and it's not even finished yet. I'm supposed to be the only one silly enough to do things like that to a 750 twin :laugh: :laugh: :laugh: :laugh:

It looks to me like the bike is setting at the proper loaded position, assembled and gassed with a rider on it. I think you should probably raise it at least two inches, since the shock will be at almost full extension under no load conditions.

If you are talking about the angle of the shock, looking at the linkage it appears to me that it should mount as close to vertical as possible.

Btw, I'm extremely jealous
Gsxr front and rear, sheesh

Post edited by: steell, at: 2006/03/26 12:17

Thanks everyone.
I have been trying to put a lot of thought and research into this before I ask questions. But I really want to make sure I get this right the first time.

I am sure thats how its supposed to sit, its not backwards. I have a parts skematic of the piece. here is also a pic of it still sitting in the original bike. Not to clear. But you can see it looks like a similar height and so forth.



I am mostly concerned with the angle and distance of that bottom mount. I think I might mount it about -40 degrees from level. Around where it is. I just cant find a pic of the linkage from below on the original bike. That would make me feel a lot better.

Oh and steell,
I know everyone tells me its a waste. But I am going for looks as well as performance. So I like the look of the twin, and its my first project like this. Plus it was cheap!
What have you done on yours?

Yep, for me cheap is good

77 750 frame with 83 GPz750 front and rear (monoshock), but I have a GPz750 to compare it to, so that made the mounting a little easier

I'm using GPz900 tank and bodywork, and the GPz900 fairing if I can find one cheap.

Basically I'm building a GPz750T (for twin)

I already had most of the parts, so I figured why not?

At the moment I'm working on the motor, 1 mm oversize pistons with a milled head, should be 9.5-10:1 compression (and kick start only) with EFI.

I think you should probably raise that lower mount, there won't be much movement of the swingarm before the linkage is maxed out at that angle.
The stock 750 twin has pretty slow steering, I think you should make the rear set higher than stock to quicken the steering a little.

Post edited by: steell, at: 2006/03/26 13:07

very nice, do you have any other pics of your rear suspension setup?

I am now also trying to decide what the best method would be to make the top support. I think I am going to start with a 2x2x1/2 plate. I need to see it to visualize how to support it.

I was thinking either 4 pieces of 1" frame tubing with a little bend going down to the plate from above. or If I should just box it in with angle for the battery to be right above it.

I dont really want to use a side cover. So I want to make it look nice and clean. But I do need a place for the battery and other electric goodies!

Oh and Biquetoast sorry missed your ?

I pressed out the pivot rod on the stock kz lower tree, and made a adapter to fit it in the gsxr lower tree. Then I had to bore the top tree to fit the larger rod. That was it. As long as you have access to a lathe/mill and a press , its easy.

Post edited by: Jornum1, at: 2006/03/26 13:14

Looking good! I think you know what you're doing. do the gixxer forks lower the front any? that should quicken the steering too right?
Scott

looks pretty good. if you want a softer ride. then mount the rear spring leaning slightly forward like two wheeled terror. if you would like a firmer ride. then mount it more straight up and down. that is what i did. i would recomend tilting it forward slightly.

mine is straight up and down. i have a swing arm off a 03 gixxer also.. i am mounting 2001 gixxer front forks on. but i like my ride stiffer than most people.

what size bearings did you use to mount your front forks on ? what numbers did you use and where did you get them from please.

Thanks. I was able to clean up the mounts and tack them up to day.
SBjones, do you have any pics of how you mounted your rear shock? I bought the bearing from Jeff at Z1 Engineering.

try a pic here.

like i mentioned. my shock is darn near straight up. so this gives me a firm to rough ride. it is really stiff.

but i have a really sticky tire is the rear (racing tire rear and front) so i like this set up for me. i would recomend tilting it forward a bit.