brake upgrade, twin disc.

[Tom550]

I am going to just do a single dual piston upgrade on my 1978 550 but am really wanting a twin disc. Can I use 750 forks to get the mounting tabs? Or are they different? I was reading that the gs550e's forks don't work? My 550 only has the left side mounting tabs, just wondering if it's possible. Of it's spokes if that makes a difference.

[Nessism]

Should work fine.

[Tom550]

Sweet! So 750 forks are the same? I'm going with homemade braided lines too. Thanks a bunch man.

[salty_monk]

GS650 ones should work too.... What you will find though is that the power of the 550's single brake with it's bigger rotor is just about the equivalent of the dual rotor setup with the smaller rotor (all duals are smaller..)

Your net gain would be approx zero...

You could do the Kawasaki mod to the new forks though...

[tkent02]

Your net gain would be approx zero...

)

The dual brakes stop a LOT better than the singles.

[Tom550]

Ah, all these brake things are driving me crazy! So since I realized I needed new forks to do the twinpot, I decided to go with the 550e's twin disc and am wondering if the rotor is different. I have a non E with a single disc and was going to get the right lower with tabs and the caliper and rotor. Is this possible? Do I need a smaller left side rotor? Or are the non E's single disc caliper mounting in a different location? Thanks guys for the help in advance.

[Big T]

The E forks are different, you'll have to buy a pair

The dual discs are smaller, the caliper mounts are lower down the tube and won't match with the single disc fork

If you're going to do the twinpot, you'll need:

1. E forks
2. Wire wheel disc rotors (1 more)
3. SMs adapter kit
4, Twinpot calipers
5. Hoses for calipers

This should work on your existing wire wheels. Pop off that plastic cap on the right side of the hub, where you think the rotor should bolt on, and see if the bolt holes exists and are tapped. Then, replace the cap.

I did the twinpot upgrade on my 78 1000, huge, huge difference in braking power

[Tom550]

Wait, so the e forks work with the twinpot upgrade? I was told I needed 650 forks to do this.

Okay, I'm now just trying to get a dual disc e setup for now. Money is tight. So what would I exactly need? I am about to buy forks and other items from members here and I don't want to buy the wrong part. So the tabs on the forks are the only change in the twin "e" setup? Rotors and calipers are the same?

I'm guessing I need:
both "e" forks, one caliper and one rotor. But that's if they are the same. Thanks.

[salty_monk]

The dual brakes stop a LOT better than the singles.

Not in my experience but you have ridden more of these than I have...

The 550 I had stopped better than even the stock 83-750ES that my friend had (ex-nessism) with braided lines.

To swap over to a dual brake setup you'll need:

1. A pair of forks from an E of the same diameter tube. If I remember rightly it's 35mm so a set from a 650 or a 750 would work. You may also need to use the triple trees - not sure on that.

2. The 264mm dia rotors from the dual disc setup.

3. At least one extra caliper possibly two.

One thing you may not have thought of is running your existing brake with 1 of the smaller ones on the other side - you need one fork leg, 1 rotor, 1 caliper then. BadBillyB did that on his 1000C from memory. Might save you some cash if money is tight...

[Tom550]

Ah I see, so even the 550e forks would work with your special brackets?

Yeah money is really tight as I'm eighteen. I bought the bike with my grad money and have been restoring it with a 50-70 dollar a week income ( I do yard work for my old teacher.)
Hopefully a job will pop up. It's driving me crazy having to compromise on what I want my bike to be. The problem is I don't even have a working brake. I was going to buy a rebuild kit but they are pretty pricey and don't even come with a piston! I guess I'll have to see how much the forks are going to be and how much the calipers are. I think I'm going to buy both forks and discs, brakes is something I really want working perfectly. The bike I learned to ride on was a 85 gs550l and it had a terrible brake which made me lay it down a few times when it locked up.. never want to deal with that again. Do it right the first time I suppose

[salty_monk]

Nobody has ever mounted it on the 550E twin rotor forks but I don't see why it wouldn't work.....

May be easier to hunt Ebay for a complete front end...

If you don't have a lot of money the cheapest way is probably to stay stock... the stock brakes are "adequate". It's nice to have the extra especially 2 up but you'll be ok if with the stockers if you ride with the brakes in mind.