Slipper clutch conversion project

[ashdricky]

I am very interested in fitting a slipper clutch to a 78 gs550 crankcase, my thought was to take the clutch basket from my 78 parts bike, and use the clutch from a 2007 GSXR. my goal it to find some way to make a 'hybrid clutch'. I have access to Tig welding equipment as well as a local machinist who has loads of spare time. What issues will immediately need to be overcome? I haven't ordered the gsxr clutch yet so I dont know it's proportions compared to the gs clutch.

I should also say that my projects usually move at a slower pace, and my frequency of updates reflects that.

thanks-Rob

 

[Guest]

I'm not sure what you are going to run into . But sounds like it would be a neat project. Although I don't think you need 2 posts on the same subject. The people on the forum will answer a single post if they have your answer. 2 posts are not going to get you a quicker answer.

 

[ashdricky]

sorry for the double post, I thought maybe people would look in the performance threads rather than drivetrain, wont happen again
dose anyone know if the baskets are similar in dimension? is there an outside company that manufactures the clutches for Suzuki? or are the created within the firm?

 

[GregT]

I'm assuming here that by slipper clutch you mean a back torque limiting clutch - as the late GSXR1000 has standard.
To the best of my knowledge the slipper workings are all in the clutch hub - not the basket. If the mainshaft splines are the same and the GSXR hub will fit you can do it easily IMO. If the splines are not the same, it's gonna be a hard job - and possibly quite expensive too even if you have machining capacity.
Currently, I'm waiting for a friend who maintains a front running GSXR1000 here in NZ to do some clutch maintenance. At which time I'm going to check out the splines for myself.....

 

[ashdricky]

I'm assuming here that by slipper clutch you mean a back torque limiting clutch - as the late GSXR1000 has standard.
To the best of my knowledge the slipper workings are all in the clutch hub - not the basket. If the mainshaft splines are the same and the GSXR hub will fit you can do it easily IMO. If the splines are not the same, it's gonna be a hard job - and possibly quite expensive too even if you have machining capacity.
Currently, I'm waiting for a friend who maintains a front running GSXR1000 here in NZ to do some clutch maintenance. At which time I'm going to check out the splines for myself.....

Yes back torque limiting clutch is what I meant, If the splines are the same then all that would have to be machined is the helical gear that meshes with the crank gear right?

 

[GregT]

Yes back torque limiting clutch is what I meant, If the splines are the same then all that would have to be machined is the helical gear that meshes with the crank gear right?

Wrong...the basket and primary gear would be unchanged. The hub which is the piece which carries the springs and pressure plate is a two piece construction. When it sees back torque, balls or rollers ride up a ramp between the pieces. As the clutch spring pressure keeps the two pieces clamped together and driving, separating the two pieces releases spring pressure and the clutch slips.

There are aftermarket slipper clutches available for several Suzuki models - the 650 and 1000 V twins as well as the current big fours. It's possible that one of these may have the right spline. Or if your buget is big enough, the makers will do custom applicatons.

 

[ashdricky]

I did try to do a search for gs1000 back torque limiting clutch and gs1000 slipper clutch with no results, but i will continue the search. We I am funded by a part time job and student loans right now, so I don't think that a custom order is possible. do you have a link to one of these clutches? did suzuki use the same clutch in all their 4cyl bikes?

 

[ashdricky]

So I just ordered the clutch assembly from an 07 gsxr 600. As soon as I get it I will report back with measurements and if anyone has a spare 550 clutch lying around that they would sell I will happily take it off of your hands

 

[salty_monk]

I believe the VX 800 has a slipper clutch, that might be a fit too....

 

[ashdricky]

thank you Monk, Im searching for the vx800 and can't find many parts for it, was it only sold overseas?
EDIT: Just checked ebay.de and I find many more results, Is it possible that this might bolt right in?

 

[bwringer]

I'm sort of wondering why in the world you feel a wee 550cc four cylinder engine needs a slipper clutch in the first place.

 

[bwringer]

thank you Monk, Im searching for the vx800 and can't find many parts for it, was it only sold overseas?

The VX800 was sold in the US in 1990-92.

I know because I had two of them, both sold.

There are very, very few in the US. It was a fantastic bike, but sold very poorly. It was too elegant for the tacky '90s -- anything that wasn't swathed in hideous cracking cheap plastic with neon graffiti stickers all over it didn't stand a chance at the time.



Anyway, the VX800 did indeed have a slipper clutch. No idea whether any of the parts would be in any way compatible with a GS550, or exactly how you'd get the thing to activate with teacup size pistons.

Again, back-torque is the very least of the 550's problems, so I have no idea why you want to do this.

 

[ashdricky]

The VX800 was sold in the US in 1990-92.

I know because I had two of them, both sold.

There are very, very few in the US. It was a fantastic bike, but sold very poorly. It was too elegant for the tacky '90s -- anything that wasn't swathed in hideous cracking cheap plastic with neon graffiti stickers all over it didn't stand a chance at the time.



Anyway, the VX800 did indeed have a slipper clutch. No idea whether any of the parts would be in any way compatible with a GS550, or exactly how you'd get the thing to activate with teacup size pistons.

Again, back-torque is the very least of the 550's problems, so I have no idea why you want to do this.

hahah! I was just reading how the vx was indeed sold in the us, I need the BTL clutch so I can use a quickshifter on the downshifts as well as the upshifts. although they are still teacup sized my 550 now has 650 cylinders. Do you think there might not be enough rotational force to engage the clutch? and if so would installing lighter springs for the torque limiting mechanism solve such an issue?

 

[ashdricky]

The 2007 GSX-R Clutch arrived today, and I am taking photos to document my effort. I will upload pics as soon as possible.

 

[Toasty]

This is definitely going to be an interesting project!

 

[JEEPRUSTY]

What a grand project.
Pics are an awesome thing so keep em coming.

 

[ashdricky]

Here is the GSXR clutch next to the Transmission out of a 78 GS550.

And here is the actual Back Torque limiting mechanism,

The splines match perfectly....

 

[ashdricky]

By Friday we will have another 550 clutch and then I can match up the baskets and sort out the possibilities.

 

[ashdricky]

the 550 clutch is here now and within a few hours I should have photos up for comparison, anyone have any direction or place to start now that i have both? My bike is in storage temporarily so I cant test fitment yet, but i figure that the 550 clutch should give an accurate perspective

 

[GregT]

Did the center hub fit the splines of the 550 mainshaft ? Looking at one of your pics it would seem so...
Don't change the basket/primary gear just run the slipper center in the 550 basket. Use 550 steel plates and the GSXR fibers.

Looks like it's all feasible. I was half expecting the GSXR center to have fine splines like the air/oil cooled motors.