Front Fork Spring options. 1986 and up

[Redline Junkie]

Any know of a good source for stiffer springs for 1986 and Up RZ350?

I have had mine on the track lately and it is scary soft, even after making some preload spacers. I think the progressive springs I see for sale are a different length then the newer bikes?

Thanks

[kpke]

Off Road may be able to help you out, eh? He's always messing around with fork springs.

[Darrell]

I bought Progressives for my 89 and they work great. It's been many years ago now, but MAYBE I still have the PN.

[85RZwade]

Race Tech probably could help

[Bare]

Stock spring are silly soft/useless. Spacers ?preload are a waste of time Only compensate for Overweight riders.
Don't help handling (Spring rate .. in the least) Easy solution is to cut 4 coils (minimum) from the oem springs.
Then fit pieces of PVC pipe as compensating spacers.
This Works

[brrrappp]

Stock spring are silly soft/useless. Spacers ?preload are a waste of time Only compensate for Overweight riders.
Don't help handling (Spring rate .. in the least) Easy solution is to cut 4 coils (minimum) from the oem springs.
Then fit pieces of PVC pipe as compensating spacers.
This Works

This is correct, a shorter spring will act as a stiffer spring to the point where coil-bind starts.
Also as another post mentioned, Race Tech has several different spring rates available, they are a great source and have some guidelines for rider weight and usage, racing v street.

[Srhiskx]

Check Sonic Spring. They offer 5 different weights for the RZ350. I went with an 80 weight straight wound spring for my RZ. Made a difference in my front end. I had progressives in it before and they were way too soft. Esp under braking.

[Redline Junkie]

Thanks Everyone!!

[kobra]

I went with .80's in my RZ and it is amazing

[Redline Junkie]

I went with .80's in my RZ and it is amazing

Kobra, did you go with Race Tech or Sonic springs?

[kobra]

I went with .80's in my RZ and it is amazing

Kobra, did you go with Race Tech or Sonic springs?

Sonic springs.

Also the MikesXS gold valves. I did a lil write up here about it.

viewtopic.php?f=5&t=15612&p=168872#p168872

[JonW]

Back in the day we rode the wheels off these bikes with the OEM suspension. You could always look for nos springs as well... I found a set for my OEM F2 build a while back, cheap too. At least you would be 100 sure they would fit, not all aftermarket suppliers get that these forks have different parts over the years.

[(F5)]

Stock spring are silly soft/useless. Spacers ?preload are a waste of time Only compensate for Overweight riders.
Don't help handling (Spring rate .. in the least) Easy solution is to cut 4 coils (minimum) from the oem springs.
Then fit pieces of PVC pipe as compensating spacers.
This Works

I did this back in the day, you take them off the tighter coiled end. Might have been a bit more greedy.

But.

You must then heat and bend last coil down carefully. Then grind the end square flat, else the spring will be forced like a wedge against the side. Make preload spacer to set for correct sag.

Geez they used to dive like a submarine on the brakes as std. But all yams were like this even my 1993 YZF750SP which was pretty stiff in the rear was too light in the front.

[vintagetz]

Stock springs are too soft, the mfg doesn't want to get dinged for a "harsh ride". If you get up to a good pace they will chatter you to the edge of the track if you don't get out of it or slow down.

The rule of preload is if you should NEVER have more than 20mm of preload, I don't run more than 10mm.

Traxxion Dynamics is a great source for springs.

I run .85 to .9 KG straight wound springs in my race forks with emulators (with the damper rods drilled out), and 20wt fork oil. I run 10mm or preload. Installing the Emulators is not hard, you just need a small pilot bit and a 5/16" or 8mm drill bit to open the compression holes up. it can be done with a hand drill and a vice if you are careful (protect the rod from the jaws)

I think the spring size is 27mm X330, The RZ has a longer fork than the RD400 Daytona or my TZ forks if a longer spring is available it will reduce the length of the pacer you will need. You might run as light as .8kg on the street depending on your weight. I would run the same springs I race with if I rode on the street.