XJ550 Seca rear disk

Hey All,

Looked all over, but can't find a decent answer. My current setup is an 83XJ 550 Seca with FJ600 motor, GSXR 750 front, and some other goodies, but I would like to go to a disk in the back. I have an entire FJ600 rear end (swing arm, wheel, brakes, etc) and I'd like to swap the wheel and brake setup over. I do not plan on running the swing arm and going monoshock. Does anyone have any experience with this?

Thanks!

 

Not seen this done yet but I guess the first thing to do is measure the width at the rear spindle to check if the entire gubbins will even fit. Then you'll have to figure out caliper
mounts etc.. If my experience on this type of thing is anything to go by it will be at least twice as tricky as you think. Keep us posted

 

Luckily I'm friends with some really good bike builders, so fabricating a caliper mount wouldn't likely be that difficult. I do know that the FJ motor lined up with my XJ wheel with no issues when I swapped the motor. That being said, the swing arm and wheel could be wider on the FJ and the FJ motor output shaft aligning with the XJ wheel could be purely coincidental. I have loads of stopping power with the dual 3 pistons up front, but I would definitely like more back brake to balance it out.

 

The 600 motor is essentially a bored and stroked 550, that's why stuff lines up

 

I was told the Radian and FZ space the drive sprocket out to clear the wider rear wheels. The FJ has a skinny rear like the 550. I’ve never verified this. The Maxim is wide, who knows if it’s same as Seca?

 

I've got a Radian motor in my 550 - haven't noticed any line-up issues.

 

I put an FZ motor in a girlfriend’s FJ back in the 90’s and was told of the misalignment. I didn’t notice any either and she sold it shortly after. As I said I never verified this.

 

I just looked up the output shaft of the 84 FJ and the 86 FZ, they have the similar numbers 17402 but 4G0 prefix and 46X prefix, whatever that tells us I don’t know ?

 

This is a "kitchen sink" set up on a Xj550 Seca with a Suzuki GS rim, a CBR600rr F3 rotor, and a Suzuki Bandit under slung caliper hanging on a Xj600 Seca II swingarm. An R6 master cylinder with generic braided hoses makes everything work right. The caliper stay is scrap from the Boeing Surplus store. This isn't a bolt on arrangement.
You can scab anything together from a multitude of bikes and have it work correctly with some research and ingenuity. Very little will be just bolt on for this set up.
Many believe that its easier to be faithful and use only Yamaha parts, which is cool and I respect that. It does limit the possibilities,the parts available and probably ups the price.
Alignment issues, if minimal, can be addressed with offset sprockets or machined wheel spacers.

 

FZR600 rear set up? ⬆️

 

seca 550 runs same motor as the maxim 550 just has hotter cams and different carb jets. seca550 has 18 inch rear wheel to the maxims 16 inch wheel but you can swap the rear wheels.

there is an old thread of a person who was making kits to convert rear drum to disc.

 

It have a Katana rear 17," wheel GS500 hub, Early FZR600 swinger.

 

Very nice set up, indeed.

 

Bike already has a GSXR front end, so that's out the window. Thanks for the info everyone. I'll probably mess around with it this winter. I have to do some more work to the bike to get it to where I want it, but it's finally getting close. Now I just need to decide if I want to drop money on a disk rear setup, or a rack of flatslides to really open her up.

 

Thumbs up for the secas with gsxr front ends. I know that the XJ650 has a rear disk option though a company cognito Moto. I picked up my triple tree setup from them, and in the future will swap to spoked wheels and do the rear disk conversion.

 

If you've did the GSXR forks swap yourself the rear disc is about the same level of difficulty.
You got this....

 

Honestly, I have a full FJ600 parts bike and I may just go mono on the back. I'm not super great at welding, so I'd probably have to enlist some help with it, but I've got some friends that build some wicked bikes (These guys http://www.mantramoto.com/yamaha-xv750-virago/).

I did the GSXR front end myself. Honestly, it was super easy. The front end I sourced was a complete plug and play.