GS1000 twin disc upgrade, problem! Solution?

[Billyboy]

I bought a right fork and caliper to make my GS1000C a twin disc up front.
I got the parts a while ago and got them prepared. Put the progressive spring in, oil, preload, polished. Took apart both calipers. Checked them all out. Good

Polished up my spoked wheel, bolted up my spare disc, changed over a new front tire. Awesome...

Yesterday I tried to mount the wheel on the forks. It went on the forks just fine, but when I tried to mount the calipers, I found that THE DISC IS TOO BIG!!!. (Imagine my frustration)

Upon investigation I saw that the right (E model) fork caliper mounts are about 1/2 inch lower than the left (C model) caliper mounts!!!

Would I be correct in assuming that Suzuki used a bigger disc on the C model single disc, and smaller diameter discs on the twin disc E model?

If this is the case, would I be able to simply used my spare rear 280mm disc on te right side?[-o<
I know it might look wonky, but it'd take a discerning eye to notice it.

[Tom MLC]

I bought a right fork and caliper to make my GS1000C a twin disc up front.
I got the parts a while ago and got them prepared. Put the progressive spring in, oil, preload, polished. Took apart both calipers. Checked them all out. Good

Polished up my spoked wheel, bolted up my spare disc, changed over a new front tire. Awesome...

Yesterday I tried to mount the wheel on the forks. It went on the forks just fine, but when I tried to mount the calipers, I found that THE DISC IS TOO BIG!!!. (Imagine my frustration)

Upon investigation I saw that the right (E model) fork caliper mounts are about 1/2 inch lower than the left (C model) caliper mounts!!!

Would I be correct in assuming that Suzuki used a bigger disc on the C model single disc, and smaller diameter discs on the twin disc E model?

If this is the case, would I be able to simply used my spare rear 280mm disc on te right side?[-o<
I know it might look wonky, but it'd take a discerning eye to notice it.

Wow Billy, I never would have expected that!

I do know that when I put '83 GS1100 wheels & rotors on my '78, the calipers were hitting the spider web pattern on the inside of the rotor. That's 'cuz the '78 rotor surface area is wider. 295mm, I think. Anyway, the solution to my dilema was to find '80 GS1000E calipers. They bolted right up to my forks, and fit well with the '83 rotors.

Your situation sounds different, I know. If you try the 280mm rotors, look closely at the surface contact. You may not be biting the whole rotor.

[Billyboy]

I'll giv it a try tonight.

[Billyboy]

Anybody else have any idea about this?

[SqDancerLynn1]

Single disk - the disk is thicker & larger . Dual disks are thinner. USE THE thinner proper disks

[Billyboy]

Single disk - the disk is thicker & larger . Dual disks are thinner. USE THE thinner proper disks

But the left fork and caliper fit the single larger disc and the right fork and caliper fit the smaller disc.

I've got one fork for the big one and one fork for the small one.

[8trackmind]

I've got one fork for the big one and one fork for the small one.

Correct. Single disk bikes use a larger rotor.
You need both lowers from an E model for a dual brake conversion.