Rear drum brake for GS1000

[wera racer]

I'd like to lose the stock cast wheel, disk and rotor on my 78 GS1000 race bike in favor of a drum spoked hub and aluminum rim to lose all the excess weight, especially since the rear brake isn't used in racing (or rarely).

Anyone know of a good swap for this? Thanks!

[tkent02]

Early GS 550s had a drum, I think the axles and things are the same size. It had a steel rim, so you would have to lace an alloy rim from an early GS 1000 to it.

[Big T]

Why not a GS 1000 spoke rear wheel with a smaller disc and caliper?

[Big Rich]

Depending on the width of the hub, look into the GT550 and GT750 wheels as well. 36 spoke with a 2.15"*18" steel wheel stock.

[sharpy]

And who says rear brakes arent used. Have you seen Haydens brake setup? Bigger than his teammates

[Nessism]

Trail braking while entering corners is a valid technique effecting chassis stability.

I think the lighter disc and caliper is a better idea. The stock disc could be thinned to lighten it some if nothing else.

[wera racer]

Haydens I'm not Just a middle-aged vintage racer in only his second year on the track.

Most of the guys I race with don't use the rear; some even just have what looks like a rear brake to pass tech but isn't. I like having a rear just in case...especially if I go off the track.

A drum is just simple and clean (and looks more period correct, especially with spoked rims), and provides just enough brake for trailing (if I ever get good enough to do that) and emergencies (like my very fast Road Atlanta T1 off-course excursion). Here's an example (not mine, by the way):



I'll look into the GT550 and 750 setups; no joy yet on the GS550 wheels on eBay.

Thanks!

[hampshirehog]

Easiest would be to fit the early 550 (or GT as above) drum. Axle size is smaller but just use 1000 wheel bearings to overcome this and it'll fit right in. You'll have to mod something for the brake stay / cable on the frame but pretty easy.

Rear drum isn't such a bad idea. The rear disc is a bit too powerful on the lighter bikes I think - too easy to be on full for a ham-footed rider like me. Drum 550s do have much more feel.

[SeanGSUK]

Laced wheels on a UK spec '78 GS550E

Just bought some GT550 wheels for my GS550, although it has a GS750 rear swing arm, wheel and axle.
I think the front is a straight swop though, I will update this when I am sure as I think other people would benefit from the info.
Now I just need the rear drum/shoes/cable and I'm there.
Does anyone know if the GT550 and GT750 rear drums are the same?
550 drums are like hen's teeth, yet 750 drums are plentiful. Would save me a whole heap on postage from the US if I can use a 750 drum.

[Big T]

If you go to a drum, you'll need a different mount on the swing arm for the brake stay as drums are generally on the bottom

[GregT]

I'd like to lose the stock cast wheel, disk and rotor on my 78 GS1000 race bike in favor of a drum spoked hub and aluminum rim to lose all the excess weight, especially since the rear brake isn't used in racing (or rarely).

Anyone know of a good swap for this? Thanks!

Okay, the others have given you ideas for the swap...now I'm going to try and deter you...lol.

The best period mod for these bikes was going to cast wheels. Wheel stiffness has a major effect on handling particularly with heavy bikes which have quite flexible frames and forks.
I get quite a buzz from watching the guy riding the GS1000 I look after back it into corners - he uses a combination of back brake and engine compression. He's also working the clutch once it's crossed up as it doesn't have a slipper. On some tracks it's really useful to be able to use th back brake to bring it around.
The modern "I don't use the back brake" attitude is most definitely not the fast way to ride these things.
If your regs permit using modern wheels I'd suggest fitting lighter ones and possibly a smaller/lighter rear disc and caliper. If they don't then thin and drill the std disc.
Don't know what rear you're currently using but the std 17 rear is not the way to go. The wider 18 from the 16V 1100 drops in and works better as the tyre sidewall is lower - hence stiffer.Modern 17's of course are better again.

[kochic]

Let me check, i may still have a gt750 rear wheel.
If i find it i have suzuki NOS brake shoes for it.
Marc

[Big T]

Haydens I'm not Just a middle-aged vintage racer in only his second year on the track.

Most of the guys I race with don't use the rear; some even just have what looks like a rear brake to pass tech but isn't. I like having a rear just in case...especially if I go off the track.

A drum is just simple and clean (and looks more period correct, especially with spoked rims), and provides just enough brake for trailing (if I ever get good enough to do that) and emergencies (like my very fast Road Atlanta T1 off-course excursion). Here's an example (not mine, by the way):



I'll look into the GT550 and 750 setups; no joy yet on the GS550 wheels on eBay.

Thanks!

Weraracer,

Just a thought, but your example here has about $1,200 or so tied up in wider rims, spokes and such before getting to the modified brakes

Do you think that's enough cubic dollars for what little you may gain?

Listen to Greg T, he's been racing these things for decades. If you want to go faster, spend your money on some training, like Doug Polen or some other racer

[salty_monk]

The stock GS Caliper can be used with a smaller rotor with a customised Hanger... also check-out Dee's (or maybe it's Billy's) 750, that uses a more modern "on top of the swinger" caliper.