swapping front rotors from 79 750 to 83 1100

[suzuki jim]

are the dimensions for the front rotors the same for a 1979 gs750 and a 1983 gs1100? the pattern [design] is different, yet the bolt pattern for the rotor mounting holes are the same. if anyone has experience with this question,it would be greatly appreciated. regards, suzuki jim

[John Kat]

I don't know for sure about the GS 750 rotors but I believe they are the same as the GS 1000 E non slotted rotors.
The rotors that came on the GS 1100 ( and the later GS 1000s) are slotted and while they can be mounted without any issue they require different calipers
The good news is that these calipers will fit the "older" forks.
It's a worthwhile improvement specially under wet conditions!

[suzuki jim]

thank you, john kat

i appreciate your rapid reply, sir. as you may know, the front calipers on this particular 1979 gs750 mount directly to the lower fork tubes mounting tabs, which are cast into the lower fork tubes. the 1983 front forks have the cast mounting tabs as well, however , the 83 1100 has a caliper mounting bracket which bolts to the cast mounting tabs. the caliper is installed into/onto the caliper mounting bracket,which is not an integral part on the 79 gs750.even though these two different models have different set ups for the caliper location, can anyone answer if the dimensions [height of rotor,outside diameter of rotor,brake pad area on rotor surface] are the same for these two different year/model gs rotors? thanks again, and your gs1000's are very sharp,very clean. i particularly dig the gold wheels on the red model. was that factory issued? nice! thanks a bunch. regards, suzuki jim.

[John Kat]

I don't own a std GS 1100 but here's a picture of the caliper that fits the later slotted disks.
The fork legs are from my 1100 Katana.

And here are the slotted disks mounted on a spoked GS 1000 wheel an a GS 1000 ST wheel ( gold was a std color)

[suzuki jim]

response to katana 1100 caliper photo

hey john kat,thanks for the images [love that gold rim]. bro,the rotor i am talking of can be seen on photo of the month for july 2012,a fine looking 1980 gs550et. however,it is sporting a caliper [with caliper mounting bracket] just like the one on your 1100 katana. the rotor i am talking of can also be viewed on the march and june 2012 photo of the month selections. these two bikes do not appear to have caliper mounting brackets, the calipers are just bolted to the tabs on the lower forks.perhaps my answer is on the photo of the month for july 2012. would like to thank you sincerely for your effort in finding an answer to my question and would dig talking to you someday, because i can talk a whole lot better than i can type.thanks again. regards,suzuki jim