Fork preload

[DieselTwitch]

I was told by my dealer to ramp up the preload on front forks as far as it will go. I did it, seams to work ok. just wondering if it was a good idea. I never rode it without. Does seam like it hits a little hard in the packed.

ideas?

 

[Jon Mutiger]

If your running stock springs on a 500, they are too soft.. You can add more oil so that you don't bottom out your forks on your clamps as often. Turning preload doesn't change the spring rate, only the initial force required to move the forks. What that means is a slight harshness. You won't notice a big difference on snow. You can go excessively stiff on snow and not ever really feel like you've gone too stiff.

I've found that what I like the best on snow is a SUPER stiff setup, I've got the 500XCW with .52kg/mm front springs, and I'm running a very high oil level so ensure I cannot physically bottom on my clamps as I have them up as far away from the axle as I can to get the most amount of bend resistance on the chrome.

 

[JimBridger]

You mean compression? Pre-load isn't adjustable. You can change to stiffer fork springs though. Firming up the compression damping is a good thing imo. I don't know about " all the way" but some more damping I think is a must.

 

[DieselTwitch]

You mean compression? Pre-load isn't adjustable. You can change to stiffer fork springs though. Firming up the compression damping is a good thing imo. I don't know about " all the way" but some more damping I think is a must.

Pre load is adjustable on a WP fork. Along with compression and rebound

 

[DieselTwitch]

If your running stock springs on a 500, they are too soft.. You can add more oil so that you don't bottom out your forks on your clamps as often. Turning preload doesn't change the spring rate, only the initial force required to move the forks. What that means is a slight harshness. You won't notice a big difference on snow. You can go excessively stiff on snow and not ever really feel like you've gone too stiff.

I've found that what I like the best on snow is a SUPER stiff setup, I've got the 500XCW with .52kg/mm front springs, and I'm running a very high oil level so ensure I cannot physically bottom on my clamps as I have them up as far away from the axle as I can to get the most amount of bend resistance on the chrome.

Do you mind me asking how much you weight? Im 185-190 w/o gear.

That seams like a good idea. I have not ever rebuilt the forks on this bike. Maybe I'll do that this christmas and add some more oil.

Can I ask why we want stuck a stiff setup? I was thinking the opposite. My train of thought was that the softer front end would allow the ski to pull up on the top of the snow easier.

 

[JimBridger]

Pre load is adjustable on a WP fork. Along with compression and rebound

I didn't know that.

 

[Jon Mutiger]

I think the harder the ground is the softer the suspension should be, and the opposite is also true. So snow is generally pretty soft and from my 6 years or so on snow, stiffer definitelysee seems better.

On the open chamber forks on the xcws the 21mm hex on the top of the forks does externally adjust preload. On the closed chamber forks it is not externally adjustable.


I'm slightly heavier, maybe 195 before gear.

Jon

 

[Hbmtr]

I have a cr500 with stock forks. How do I add oil, and how do I know how much to add?

thanks

get a service manuel ,it will give you min. and max oil levels for the forks and show you how to chg oil.any competent or good shop can service them also for probaly a hr worth of labor.

 

[WASnowBiker]

Stiffer springs a must

I replaced my stock Berg 570 springs with much stiffer setup after wallowing through dips and bottoming off jumps. Unless your bike came with firm MX suspension you can't fix what's needed with oil and preload alone. All the enduro KTMs I've ridden are way under sprung to start with. The Tsled fork leg clamps are also the weakest link in the entire setup - they should have used the existing brake attachment point and not screwed up that nice fork leg chrome. You also lose the bottoming cone in your suspension - and wait till you feel and hear how nasty it is to smash into your clamps.
And…you'd think that all that extra weight in the back would lighten the front end, but the opposite is true. That flat track won't roll through dips like a wheel so a lot more momentum gets leveraged to the front. Try lifting the front end of your bike with wheels on it, then try same bike with Tsled kit attached, uh huh.
Swap the springs and your steering rides up high where it's happy

 

[DieselTwitch]

I replaced my stock Berg 570 springs with much stiffer setup after wallowing through dips and bottoming off jumps. Unless your bike came with firm MX suspension you can't fix what's needed with oil and preload alone. All the enduro KTMs I've ridden are way under sprung to start with. The Tsled fork leg clamps are also the weakest link in the entire setup - they should have used the existing brake attachment point and not screwed up that nice fork leg chrome. You also lose the bottoming cone in your suspension - and wait till you feel and hear how nasty it is to smash into your clamps.
And…you'd think that all that extra weight in the back would lighten the front end, but the opposite is true. That flat track won't roll through dips like a wheel so a lot more momentum gets leveraged to the front. Try lifting the front end of your bike with wheels on it, then try same bike with Tsled kit attached, uh huh.
Swap the springs and your steering rides up high where it's happy

Thanks for the good info. I did notice that the front was really heavy. Any suggestions as to how to calculate what spring rates are needed? I'm 185-190 without gear.

 

[Rush44]

The stiffer the better...... your wife will agree.

 

[mnsnowhawk]

Probably .52 springs as stated above on another post.

Here is a vid to help with a spring change on your forks

https://www.youtube.com/watch?v=qZJ4N9Bou6o

 

[garafajon]

Probably .52 springs as stated above on another post.

Here is a vid to help with a spring change on your forks

https://www.youtube.com/watch?v=qZJ4N9Bou6o

I referenced that video when I changed the springs on two bikes. On the second though I saved a ton of time by not even removing the tubes! You just take the caps off both sides at the same time and then lift the wheel up (and use a tie down to hold in place) and the springs come popping out the top. Way faster job!