79 GS550E front caliper question

[arturojgt]

Dears. My name is Arturo, Im from Argentina and I started to rebuild a 79 GS550E and I found that the motorcycle has some parts from another suzuki GS models.

Im right now reparing the front and rear calipers. The front caliper is not the same shown by Partzilla for my bike model, It has a front caliper "apparently" from an 81 GS550T but I'm not sure, it has rectangular brake pads.
The distance between the bolts to attach the caliper to the front suspension is 75mm.
I want to change this for a more common brake caliper like the original with a lot of spare parts, but I can't find spare parts for the one that I currently have.
I don't know the distance between the bolts in the original 79 GS550E front caliper.
Can you give me some advice about if the original caliper will fit in my front suspension?
IMG_4216.jpg

[Nessism]

Most likely yes. The bolt pattern is the same. In fact, the newer calipers are a popular upgrade from people with bikes like yours.

[arturojgt]

Thank you. Im the only one in my town with a GS550 so I dont know anyone to ask this kind of questions. I bought almost all the spare parts from EEUU so there is a chance to buy the wrong part.

[sacruickshank]

From Partzilla, it looks like the caliper mounting is the same between the '81 550T and '79 550E. Also, the 550T caliper is used on other Suzi's from that era, at least the '83 GS650L and I expect others.

I would bet the caliper from the 550T is more common (and therefore has more spare parts) than the original from the 550E.

Pic shows my calipers: original from 650L mounted and original from 550T in my hand. I have been able to find OEM replacement parts (pistons, seals, rubbers, etc.) for the rear caliper from those same bikes. Agreed that Partzilla doesn't have the front parts, but it does show the pads as available. I'm sure there are aftermarket pads as well.
PXL_20220219_133800511.jpg