What disc brake will fit GS400?

[spots25]

I've got a '78 GS400 that came with a front drum. I bought a pair of GS450 mag wheels off ebay. I've got the wheels mounted, and noticed that the front wheel is an inch bigger. Oh well, i'll just run fenderless... Anyways, what front disc brake setup will fit on this bike? GS450 should fit, is the GS550 the same? GS650?

Also, with the larger diameter front wheel, my speedo is gonna be a little off, right? Is there a way to calibrate it?

[spots25]

I don't mean to be a prick, but I need an answer to the above question ASAP 8)

please?

[IanFrancisco]

No disk brake will fit if you don't have the caliper mounts on your left fork leg. You musta got rims from an L model they run 19in. front and 17in. rear. No way to recalibrate the speedo. They lie anyway so running a larger front will make it more accurate. My '80 GS450S has 18in. front and rear. Checking www.bikebandit.com for the parts fiche shows a '78 GS400C model with a front disk and a '78 GS400XC with a front drum. Both models show caliper mounts on the left fork leg so you should be able to run a disk brake with no problem.

If you need answers fast try doing a little research on your own. Google is an amazing tool...

[spots25]

for some reason, suzuki gave me caliper mounts, but put the forks on backwards... so, I switched them around... I just bought a GS550 front brake off ebay, so I hope it fits 8)

[IanFrancisco]

Here's a '82 GS450 caliper on eBay for $20. Item# 4553822588

Ends Jun-08-05 14:30:10 PDT

The same seller might have the master cylinder too but I didn't see it listed.

[spots25]

turns out a 1980 GS550 front brake works perfectly on the '78 GS400 with '80 GS450 wheels. The FRANKENBIKE LIVES!!