Shaving pounds to add performance, ? on component weight

[ozman]

sold right here by me !
just waiting on my magnesium guy to get back to me on the finished price
ill let you know once i have a price

XR69 style magnesium sprocket cover 600 grams
standard suzuki cover is 1.3 kilos
210 plus postage

[Chuck78]

Well I spent a whole lot of time in the EBC brakes catalog this evening, and I concluded that the smaller and lighter GS500 / 83-86 GS550 caliper only has pads available for shorter height (braking surface) rotors. If I used an 91-ish GSX1100G bracket, I could mount the caliper, but with the rotor I am basing my rear brakes on, the only pads available would only contact 32mm out of the 35mm of braking surface. The RF900RR pads maybe 33mm.

So beyond the larger stock calipers, the 81-83 GS650 style caliper that came on many other models after those years is the EASIEST option, and slightly narrower and lighter than the wider original, yet uses the same pads. These pads have a little more friction material than the rotor really uses, and the 88-93 GSX1100F Katana / 83-86 GSX1150E (GS1150E?) have a newer design caliper that uses the same width pads and look to be an exact fit of friction material for the 35mm of stock rear rotor or the front rotor off the same bike that I am planning on using in place of my stock rear rotor. The calipers are longer front to rear on the bike, but not a solid block of aluminim as the original older style big GS caliper appears.

Since they didn't use the GS650 style caliper on the later models of 1100-1150cc bikes (they did use the 650 type caliper on the shafty 1100's and 850's, as well as the 83 750E and others), and they used the newer (usually gold painted) Tokico caliper on two really serious bikes, the 83-86 GSX1150E and the 88-93 GSX1100F Katana, there must be some performance advantage to using that caliper. Does anyone have one of these they can compare weights on?







Also, the '00-03 VL1500 Suzuki uses those pads and a 276mm rear rotor, and a Tokico caliper like the GS500/83-86GS550E caliper I was trying to use (but fit with larger pads appropriate to this rotor), but a completely different style bracket. More bracket material, but the most minimal caliper that fits the pads that this rotor needs.

[wegs426]

Another note, good or bad maybe depending... BEWARE some GSXR calipers look practically identical to the Tokico caliper I am trying to use, but they have the bleeders upside-down and the brake stay mount on the opposite end for underslung placement of the caliper below the axle instead of the old school top placement. I don't really wanna relocate and re-weld the brake stay mount on my aluminum GS1100E alloy swinger, although a custom brake torque arm/stay that extended to the steel frame would be easy and keeping with the newer trends of modern sport bikes (and lowering the center of gravity with braking parts close to the ground). 90's GSXR calipers and even an 02 or 03 Hayabusa Tokico rear caliper looked like they'd be good candidates for this kind of setup.
And an underslung caliper on a 70's vintage looking bike sure would throw a few people off, especially since most of these parts still look fairly vintage! Buying a used caliper and chopping and extending my GS1100E brake stay wouldn't cost much at all though! Food for thought, someone else PLEASE do this mod! I may eventually, but if I can end up using this GS500 caliper with the GSX1100F hanger, that is the obvious immediate plan.

I suppose that's another option, although I literally JUST nabbed a Bandit 1200 brake stay for $13 shipped that has a nice offset to clear a massive tire and I hear is a nice fit on the GS1100E swing arm to work around having to bash the 1100E brake stay with a hammer to clear the tire.

Ask and you will receive.

I'm putting the final touches on the mod but it should be done this week.

[Chuck78]

Been a while since I posted on this thread. I ended up using the same front rotor 90-ish gsx1100f (?) and the 83-86 gs1150 caliper with new ebc organic pads. I had to shorten the standard gs750/gs1100 steel brake stay and chop the end and narrow it to fit the gs1150 caliper. Carb cleaner and a toothbrush stripped all the gold pai t off. I was going to paint it black, but it looked nice in bare aluminium and I was impatient, so I left it silver.

Braking is sufficient, and substantially lighter than the heavy and overpowering stock 295mm diameter 7mm thick rotor setup. I was more than happy to swap the 1100e alloy swinger and this brake setup along with an alloy DID 3.50x18 rim in order to drop a whole lot of unspring & rotational weight in order to make the bike handle & perform better and make up for a few pounds added from going from stock 110/90-18 (4.25x18?) Tire up to a wider low profile 140/70-18. The 140 really helped with handling, although I yjink a 130 rear and 100 front would probably have been sufficient.

[Chuck78]

Oh yeah, did I mention I GOT MY BIKE DOWN TO 500 LBS WITH A HALF TANK OF GAS!?!?!?

[Steve]

Oh yeah, did I mention I GOT MY BIKE DOWN TO 500 LBS WITH A HALF TANK OF GAS!?!?!?

Not bad, considering your goal in the first post was 468.

.

[Chuck78]

realistically, if I do the electric start and battery delete, I am looking at probably 25 pounds more savings with that and a couple other little mods like the trunk delete, detabbing frame, lighter/smaller gauges, deleting some extra unused wiring, aluminium handlebars, etc. I don't think I will remove the passenger footpeg frames and adding rear sets as I had originally planned, but it is still a possibility.I might still have my machinist friend make up some aluminum axle spacers, but he is so darn busy as Am I. If I pull my engine this winter to do the 920cc big bore upgrade and fix some oil leaks, I might end up getting some chromoly tubing and doing that frame bracing, which hopefully will only add about 4-5 lbs total with chromoly steel.

so about 480 with a half tank of gas is about where I will end up for now without going to the extremes. I'm actually really happy with the way to bike handles as is, dropping 45-ish lbs made a NICE difference in maneuverability :-)

[John Kat]

realistically, if I do the electric start and battery delete, I am looking at probably 25 pounds more savings with that and a couple other little mods like the trunk delete, detabbing frame, lighter/smaller gauges, deleting some extra unused wiring, aluminium handlebars, etc. I don't think I will remove the passenger footpeg frames and you rear sets as I had originally planned but it is still a possibility.I might still have my machinist friend make up some aluminum axle spacers, but he is so darn busy as Am I. If I pull my engine this winter to do the 920cc big bore upgrade and fix some oil leaks, I might end up getting some chromoly tubing and doing that frame bracing, which hopefully will only add about 4-5 lbs total with chromoly steel.

so about 480 with a half tank of gas is about where I will end up for now without going to the extremes. I'm actually really happy with the way to bike handles as is, dropping 45-ish lbs made a NICE difference in maneuverability :-)

You might be better off by fitting a GS 1000 engine in your frame as I believe it is lighter than the GS 750 powerplant?
Also, the GSXR 750/1100 first generation wheels are lighter than the spoked wheels

[Chuck78]

yes that is true, but my criteria were to have a classic looking bike with kickstart and spoked wheels. I really don't like the look of the modern sport bikes creeping into my vintage classic 1970's Suzuki via mid-1980's sport bike parts. I'm going for the lightest barebones vintage 70's looking bike with as many go-fast/brake/wheel/suspension parts on it as I can afford. It is true that the GS1000 engine is lighter than the GS750 engine primarily due to a much lighter crankshaft and kickstarter delete. But on a street driven engine, if I just delete the battery & electric start, now my bike is overall lighter than the GS1000 engine would have it - as the GS1000 has no provisions for a kickstarter, therefore you cannot delete the battery and starter motor and associated gears.

[John Kat]

yes that is true, but my criteria were to have a classic looking bike with kickstart and spoke wheels. I really don't like the look of the modern sport bikes going into my vintage classic 1970's Suzuki.it is true that the GS 1000 is lighter than the GS 750 engine primarily due to a much lighter crank shaft. But on a street driven engine, if I just delete the electric start, now my bike is overall lighter than the GS 1000 engine would have it.

I understand
The other day I saw a modern (?)Triumph 750 with spoked wheels.
I'm sure the rear wheel hub is much lighter than the one that came on the GS 750.
Of course the chain is on the wrong side but I suppose it could be turned around?

[wegs426]

Thanks for the great inspiration and ideas in this thread. My rear setup came out perfect.