Topic: Track day bike suspension?

[DavePhipps]

I'm wanting my son and I to do some track days next year. However I do have concerns about suspension and brakes.
First suspension: is there a fully adjustable rear shock set for these old bikes. I've gotten a bit spoiled with adjustable rebound and compression damping on My modified FZR. It does make a world of difference.
Fork springs: progressive or straight wind? Does anyone make a range of these for the old CB?
Brakes: I've got stainless lines, EBC pads and shoes. Any more I can do to make these better?

I  want to make this as safe as I can for my wannabe racer son.
 

[turboguzzi]

I'm wanting my son and I to do some track days next year. However I do have concerns about suspension and brakes.
First suspension: is there a fully adjustable rear shock set for these old bikes. I've gotten a bit spoiled with adjustable rebound and compression damping on My modified FZR. It does make a world of difference.
Fork springs: progressive or straight wind? Does anyone make a range of these for the old CB?
Brakes: I've got stainless lines, EBC pads and shoes. Any more I can do to make these better?

I  want to make this as safe as I can for my wannabe racer son.
 

you might want to check the rules and class you want to race at. stock based classes will allow less mods.
shocks: was quite happy with adjustable koni (now Ikon)at the back of my 500/4 racer, there's also race tech, YSS, etc. and of course ohlins made to measure if you want to burn some $$$
i am all for straight rate in the front, you'd want around 0.8-0.9 kg/mm according to weight. front runners fit CBR cartridges in classic racers, for my level i am quite happy with stock dampers with the rebound holes shut off.
main issue i see is stock brakes. dont think EBC make any race compound pads for the stock calipers. i tried ferodo platinum pads from vibntage brakes initially and they kinda helped. But eventually you'll see the stock discs and flag calipers are a pretty weak setup and youll want to go with bigger discs and lockheed or bembo calipers. quite a bit of work involved.

[DavePhipps]

Not racing, just track days and spirited road riding. If he's inspired by the track days we may go vintage racing. My FZR is still setup for safety wiring and have the race glass in the shed so it's there if he wants it. It's funny Both the FZR and the old CB are considered vintage by WERA.

My son and I are about the same weight 178 pounds. I  really want to be able to set sag with alternate springs front and back. Does Ikon have those and is there and damping adjustment out back?

[turboguzzi]

i apply the same principles for both my street rides and racers

for sag upfront, just cut cheap PVC tubing to the right length.

ikons have SOME damping adjustment (no separate circuits), you can ask them to recommended the spring rates for you. preload adjustment is on a rotating collar with bumps. dont expect the same tune-ability as in your fzr (that's part of the charm)

just check their site for more info

[calj737]

You can also check out cognitomoto.com and the new Fox shocks he's carrying. Possibly less expensive than Ikons and every bit as adjustable.

[DavePhipps]

Thanks guys. Looking everything up now.
TG, I thought about using PVC pipe for preload adjustment but was afraid of the plastic shattering in the tube. What type of plastic tubing do you use?

I did find exactly the shock that I want but can't afford it.
http://www.yssusa.com/series-g.html

G-362 TRWL Twin — Gas Twin Shock Absorber

 I need to get out of school and get a real job, so I can afford  this stuff.

[scottly]

Do you already have dual front brakes? That's probably the best upgrade. If you want to stay with a single, a larger 750 rotor with matching caliper will bolt right on to a 550.

[Retro Rocket]

Do you already have dual front brakes? That's probably the best upgrade. If you want to stay with a single, a larger 750 rotor with matching caliper will bolt right on to a 550.

And add a sh1t load of weight....

[scottly]

Added weight or not, duals are worth it, IMHO.  Lighter rotors are also an option.

[Retro Rocket]

Added weight or not, duals are worth it, IMHO.  Lighter rotors are also an option.

For sure, not knocking the duals, doesn't Godfrey or one of the members do lightened rotors...?

[DavePhipps]

I'm looking into lockheed or grimeca calipers and alternate disc setup. I'll probably be going through many race build threads to find more info on fitting these.

[scottly]

It's not easy to fit other calipers to the CB forks...

[DavePhipps]

Bwaller and Tuboguzzi both have found or made brackets to fit brembo calipers on these bikes. With a bit of searching some PMS and a lot of reading I should be able to find some good info.

[scottly]

I said it was not easy. I didn't say it was impossible.

[Retro Rocket]

Bwaller and Tuboguzzi both have found or made brackets to fit brembo calipers on these bikes. With a bit of searching some PMS and a lot of reading I should be able to find some good info.

Leave PMS out of it for christs sake Dave.   

[calj737]

Pretentious Motorcycle Syndrome? I agree. We don't need to be pretentious here.

Strongly encourage a fork brace and a stabilizer. Imagine both Retro and bwaller would concur.

[turboguzzi]

Bwaller and Tuboguzzi both have found or made brackets to fit brembo calipers on these bikes. With a bit of searching some PMS and a lot of reading I should be able to find some good info.

Actually mounting Brembo's is not hard to do once you know what to do can send you my file for the caliper hangers if you need.
A relatively cheap disc upgrade is 80's suzuki discs. much lighter and not that much work to fit on the honda hub.

see both here
http://forums.sohc4.net/index.php?topic=44616.msg470555#msg470555

[DavePhipps]

PMS? Arghh.... NO!
On a serious note. TG I would love that file. What format is it in?
Also would you please tell me what type of tubing you use for preload adjustment?

On Suspension I know what I want but will end up with what I need due to money.

[turboguzzi]

Ju

PMS? Arghh.... NO!
On a serious note. TG I would love that file. What format is it in?
Also would you please tell me what type of tubing you use for preload adjustment?

On Suspension I know what I want but will end up with what I need due to money.

just normal gray drain pipe PVC, choose the largest diameter that will fit and put a large washer between the spring and tube.

i have the file as adobe illustrator but can export pdf, dxf, or whatever format really. just print the pdf, spray tack it and make first a 5/16" plywood template to check fit. you could easily modify it to any other caliper but the small F05 brembos are cheap and easy to find.
pm me your email address.

[DavePhipps]

I can read any format, so it's up to you. Either attach to the thread or send it in a PM.

[turboguzzi]

pm sent

[DavePhipps]

Email sent.
Also a few more questions. What master cylinder size would you use with the brembos?
Now for a new question. I despise steel rims for spirited riding, so alloy wheels will be in the future. What rim/tire sizes would you guys recommend for uses with the standard hubs?

TG I know it's not period, but at a casual glance it looks like my spare 92 FZR600 discs might fit the CB front hub. I'll do a trial fitment this weekend.   

[bwaller]

I bought a brand new 12mm Brembo master and the feel is perfect with twin F05's. It was $100 a few years ago. I use a WM3 front, WM4 rear rim. I recently switched from a 90/90/18 front Avon to a 110/80. Rear is 130/65. I doubt the FZR rotors bolt up, but as TG mentioned earlier Suzuki rotors from the 80's fit with a little help, have the same offset, are thinner & lighter.

[DavePhipps]

Thanks Brent, that was some great info.
I'll probably have the CB rolling in a month and then start collecting and fabbing parts for a winter build.
I'll have to do this slowly as my funding is very slim. I think it will be worth it in the end.
I'll feel better knowing that my son will actually have adequate brakes on his first track outing next year. 

[turboguzzi]

I have completed the build of the 500/4 racer with very little budget, think most expenisve part was the megacycle cam.

if you dont go into the engine, then you can upgrade the cycle part for track worthiness with not that much money, a set of used konis (can be rebuilt) would be your main expense.

stock rims will simply limit your choice of rubber, try to see if you can re-cycle off-road rims in the right dimensions, many MXers have 18" rears in all kind of widths