Race tech fork valves?

[Bigbill]

Question??
Is this a 50% / 50% for it and against it?

I understand one change by installing the valves with no other changes may not show an improvement.

It's like putting a four barrel carb on a stock v8. It's a waste without a bigger cam and headers. Everything needs to be tweaked in.

 

[husqyhamm]

Its a given.
You can dial a husky front end in really damned sweet with them.

 

[silverstreakNZ]

So for the 82 500 forks would you buy gold valves or just drill some holes and tune with oil weight and height . Only gets ridden twice a year and on nice terrain

 

[slosh]

I recall Andy from HVA Factory modifying the 81 -86 damper rods to the later 87 fork spec rather than use the cartidge emulators.

 

[Kartwheel68]

I think the lower the performance of the original fork the better the RT valves will work. I also think it is highly unlikely that anyone will get the RT valves to work better than properly set up stock Husky forks, at best you will break even if you spend a lot of time dialing them in and have spent $125 to get back to stock performance.

 

[Picklito]

I feel the largest problem with the early 40mm fork is that the spring was all wrong. It's way soft, around .36, and is too long so it installs with way too much preload. Fix that and you might be surprised how well they work.

While I'm also not a big Race Tech fan, they are one of the last places selling a good spring for the 40's. I use their .44, and it's designed so you cut a spacer to install it with more modern preload theory. I use whatever spacer length provides 4mm of actual spring preload.

The other weakness is the plastic ring on the damper rod. The action of that ring is the only thing in the fork that provides rebound damping. When that ring gets worn, brittle, warped, or just plain breaks, the rebound damping goes out the window. That, and the super high spring preload of the stock spring is what makes these things rebound too quickly and clank at the top.

Run a single Japanese 40mm seal, 10-15wt oil at 6-6.5" from the top, springs out/forks collapsed.

 

[silverstreakNZ]

Yea I've planned to cut the springs and thus increase rate .
See what the maths ends up at .
The 430 is prolly going to end up with 5.2 springs in the front given my current gravity

 

[Picklito]

Cut and refinish is super easy on these. PVC spacer. Done. Just do the obvious checks... don't cut so much that the spring coil-binds before the 12" of travel.

 

[Picklito]

Another thought: Imagine how poorly an 18 Husky 300 would handle if it came with .36 forks springs? Installed with 1.5" of preload!

 

[Kartwheel68]

I feel the largest problem with the early 40mm fork is that the spring was all wrong. It's way soft, around .36, and is too long so it installs with way too much preload. Fix that and you might be surprised how well they work.

While I'm also not a big Race Tech fan, they are one of the last places selling a good spring for the 40's. I use their .44, and it's designed so you cut a spacer to install it with more modern preload theory. I use whatever spacer length provides 4mm of actual spring preload.

The other weakness is the plastic ring on the damper rod. The action of that ring is the only thing in the fork that provides rebound damping. When that ring gets worn, brittle, warped, or just plain breaks, the rebound damping goes out the window. That, and the super high spring preload of the stock spring is what makes these things rebound too quickly and clank at the top.

Run a single Japanese 40mm seal, 10-15wt oil at 6-6.5" from the top, springs out/forks collapsed.

This is a very good break down of how to properly set up Husky 40mm forks. On XC/CRs I get stiffer springs and set them up with less preload, but on WRs I cut them (which slightly increases spring rate) and use a spacer.

 

[silverstreakNZ]

Is the any reason not to just use air preload instead of cutting or replacing springs ?
Just did the maths . Can cut 10 coils off and use 123 mm spacer and still have 50 mm of spare room before coil bind at max compression . Of 57 active coils this would be 17%ish firmer spring rate ? So about .42 .
What's anyone got to say about these damper holes and is this plastic washer considered ineffective /needs replacement .
Cheers

 

[Picklito]

Those look like standard damping holes around '82 era. Not sure what your asking about using "air preload instead of cutting or replacing springs."

Also wanted to add that I hone the inside of the chrome tube where that plastic washer rides. The factory finish in there is terrible! Super rough, and bare steel that can rust easily. So, this is especially important if we are trying to resurrect a set of forks that haven't had oil in them for several years.

 

[86 400 XC]

Bad washer folds over a bit and the forks clunk on top out, l hate that clunk.

Air added just makes the seals puke faster.

 

[justintendo]

Bad washer folds over a bit and the forks clunk on top out, l hate that clunk.

Air added just makes the seals puke faster.

air seems to cause leaks sometimes is right! i think the main problem with air is it always seems to make things harsher and take away "feel"

 

[silverstreakNZ]

I found the plastic ring looked like that because they have expanded and no longer fit radially . Too greater circumference . So I cut 1mm out of the gap and put them back in . Way better . No more clunk . I'll try a bit of air then look at springs . I didn't mind the forks other than the clunk before
Lower oil height 7 to 8 inch from top and 10 psi worth of air might be a fair trade off between effort and performance

 

[suprize]

air in the husky forks just makes them harsh over the stutters. release all air at every opportunity.

 

[husqvarna-parts]

Air Valve was for letting built up air pressure out

 

[GaryM]

Race tech just uses the same dia holes on the damper rods that the 86 to 87 forks come std with. When you install the valves

Again with the help of Husky John racing my 430 at Unadilla we went way down to 5wt oil - 6 inches from top. Thats after draining the 10 wt
down to 6.5 from top first from 6. I like the feel of the 5wt oil

And with the help from race tech we added two more holes in rods. And drilled the other draining holes in the valve itself to drain the oil
back to bottom.

 

[husqvarna-parts]

Use up-graded, high quality Damping rod sealing washers, not to hard to find if you know where to look. The factory stock spindle washers are inferior to what is available now.