1978 GS750 - Single Front Disc Upgrades?

[Anonymous]

Hi,

My first bike was a '78 GS750, and I haven't ridden it for about three years (a '92 Ducati 900SS took its place). I just started riding the '78 again and have found that the front disc performance is APPALLING (granted, I'm not expecting it to be as good as the dual brembo's on the Ducati). Most of the stopping power is provided by the rear disc.

I've done some searching through the forums, and it sounds like converting to a dual-disc front is not just a simple bolt-on upgrade (i.e. requires new triple tree, forks, wheel, rotors, calipers). So, I'm thinking of just upgrading the single-disc setup.

Does anyone know of any manufacturers that sell new bolt-on performance rotors, calipers, pads, brake lines, and master cylinders that will fit the '78?

Thanks for your help,

Erik

[SqDancerLynn1]

Theirs not much to upgrade with the single disk, Need a dual disk set up
Need to change the master,forks & add a 2 th disk you can use the original wheel ??

[Hotblack]

The single undrilled disk will never put you over the bars, especially in the rain, but it should DEFINITELY provide much more stopping power than the rear disc. Sounds like something is up there.

[gsBert]

does your caliper have opposed pistons or is it the sliding type?
if its the sliding type, take it apart, clean, buff and regrease the slider pins.
sounds liek you're braking on only one side of the disk. common with those types of calipers if you haent ridden in a while, my kz400 did that a lot

[Kaptain Ketchup]

I have a front end off a 78 GS750 is you want any pieces ewlotter. If this is the route you wanna take I have:

Upper and lower triples, both forks, calipers, wheel, both rotors, axle, speedo drive, etc.

Let me know. Its just sitting in my garage. Was on the road last year.

Mark

[humhead]

I've done some searching through the forums, and it sounds like converting to a dual-disc front is not just a simple bolt-on upgrade (i.e. requires new triple tree, forks, wheel, rotors, calipers). So, I'm thinking of just upgrading the single-disc setup.

Don't panic. It's not as bad as you think. You need fork lowers,a dual disc master cylinder, both rotors & calipers & a brake line. (this would be a good time to upgrade to stainless steel lines) Your wheel is pre drilled for dual discs. Look under the plastic cover on the right side of your hub & you'll see what I mean. The triple tree is the same on both models. Don't believe me?
See for yourself here: http://www.alpha-sports.com/suzuki_parts.htm

I just upgraded my 78 1000 to dual discs. I didn't have to change the triple tree. If you can get the parts, you can make the change in an afternoon's time. well woth the effort if you ask me!

Terry

[gsBert]

before messing with wahts on your bike and may be perfectly serviceable, make sure your caliper slides along the guide pins properly if it's not an opposed piston caliper, and if it is, make sure the pistons move freely, in other words, fix your caliper.

[mcycle-nut]

Before you start messing with all that, why don't you try putting on braided steel lines? I did that to mine, and it's like night and day! 8)

[gsBert]

again, let me repeat myself:
make sure you find what the problem is before you try fixing other stuff.

erik: the most likely cause of your bad braking is a piston in the caliper not sliding freely or of you dont have an opposed piston system (and i'm pretty sure you dont), the guide pins the caliper slides on are seized.

on a sliding caliper the piston presses on one side of the disk only. this causes the caliper to slide on the pins and applies pressure on the other brake pad. if these pins dont allow the caliper to slide your braking will be indeed more effective with the rear brake than the front, as you'll only be applying at best 50% of the brake.

steel braided lines are a decent idea if you do a lot of heavy braking but they will not compensate for the problem i'm describing (which is exactly the problem your 78 gs has according to your description).

now take that caliper off, hammer the guide pins out, buff them and re-grease them with bearing grease. while you have the caliper out, make sure you can move the piston relatively easily, you should. if not you may need to rebuild your caliper or get another one if you dont know how. you dont need an aftermarket performance caliper, you just need one that works

[gspaul]

Bert is dead right on most point's, you have to strip everything down , inspect , clean, replace.
S/S lines are great ,and the 750 should never have had just one disc, it was never enough!