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A couple of rides ago, the front of my bike felt like it was sitting a little lower than usual. It felt like the forks weren't totally rebounding back up. I had the guy who serviced them check it out, and he thought they were ok. Well, Monday, myself, Andy and Jim(jeb) went riding, And the front end was all over the place! It was ok in some areas, but in bumpy, ripple like areas, it just went where ever it wanted to. Maybe its not rebounding fast enough? Could it be a rear shock problem that is affecting the front? I ordered all new swingarm parts, because when i went to check the chain tension, the arm had some lateral movement. More than it should, but i don't think this would be a big issue. I didn't change or do anything that i know of for this to happen. Maybe the oil needs changed already? Only five rides on it. Thanks for any help, Rick.

You have a heavy bike with very soft front suspension. Now that you guys are riding more the front end is getting more broken in. I changed the front springs in mine and they are much better. We have no rebound controls Even though they are stock USDs they are not exactly KX quality.

For those of you (us?) that have rebound clickers...it has become very evident that rebound control is huge when it comes to front end stability.

So...since you don't have those (I gather) what will most effect rebound action is the oil itself. An oil change is likely a good idea. You're talking about the 250 I presume? If you have five rides on it...then it's been ridden a whole lot before you. Who knows how well it's been serviced. Well...I don't know what '..the guy that serviced them..' means, either. What did he do? Oil used? Maybe it's related TO what he did??

If the swingarm is wonky, that's a good indication of lack of maintenance on 'stuff'..and probably applies to the fork hydraulics, too. A one-each fluid change in the forks doesn't get them cleaned inside well at all.

Yes. It could be a shock problem.

It doesn't take much of an 'error' in tire pressure to get the front end walking around too much, too.

What is 'lower than usual'? Do you have a static sag number?

Checked your steering head bearings lately?

Not knowing the history and/or the quality of that history..it could be a number of things.

Sorry.

Let's fix it!!

Well, the guy who did the forks runs his own shop, and has been doing it for a long time. When i got the bike, the fork seals were leaking, so i took them to him. He replaced the seals, wipers, and oil. He said everything looked good. He put a medium grade oil in it. Maybe i need a heavier grade? Ive kept the tire at 12psi, and its still there. I also went through the stem and wheel bearings this winter. They seem to be in good shape. And like i said, the front just seems to be sagging a little more than it did. Thanks, Rick PS, yeah its the 250.....

Other than the fact that NO ONE that I've paid to do work on a motorized vehicle has EVER done ANYthing correctly, I guess there is no reason to assume his work is the problem.

Any chance your head bearings are loose? You're familiar with the general tapered bearing seat/run procedure?

Stiction? These are USDs, right?

Who put the front wheel back on? Was it centered? There's a process for that.

Lower clamp torque? What is it?

I put the front wheel back on. Centered? Tell me more about Stiction please. Yep, USD'S.

I don't know exactly what your front-end looks like. I could look it up...but I'm time challenged.

THIS WRTEUPis so good, there's no sense in rewriting it. Look for ski's post..4th down.

And...it covers the fork install, too.


Stiction is the initial 'break force' required to get the forks tube to slip. Some seals are worse than others in this regard...some having more stiction than others. KTMs are famous for this, btw. There are some hi-falutin' products (sprays/liquids to make the fork tubes slick) made (like forkslyk) for the express purpose of reducing stiction. Inda sells some he likes. Used to anyway.

One of the biggest factors in stiction is the torque on the bottom triple. In the KX fork for example you can readily feel the difference in compliance of the front end with a simple change between 12 and 10ft/lbs. 10ft/lbs is sufficient. Some frontend specs call for torque in the range of 14ft/lbs. That is WAY too much.

Oh..in the case of a threaded axle the procedure is pretty much the same. Tighten the axle with everything else loose..then do the wheel spin/brake thing.

How's that?

Check to see if a fork spring is broken (you'll have to pull it out to tell).

I've had experience with broken fork springs, and the sag is a little more than before, and the front end wanders.

Thanks guys. Ill check it out. I have the forks off, and when i push down on them, the first couple of inches feels a little sticky. They both feel the same. Maybe it is the seals/ stiction?

New fork seals commonly have a 'break in' period during which they loosen up.

Given it turns out to be a seal stiction issue:

If the guy that worked on them is a friend of yours, it would be good for him to know that the seals he is using (at least in your application) are too tight. He would do well to use another brand if one was available.

Something you can try..even after they're together: Fullly extend them, give 'em a dose of Triflow (teflon), rub it 'in' with your hands, let sit for a bit, buff.

Or...ask Inda if he's still selling his fork slickery stuff.

Or...ride the pee-wah out of 'em. See if they loosen up.

Good luck!

Good advise! The only thing is, I rode on them two or three times, and they were great. Then, all of a sudden, it started doing this. Im leaning towards fork oil, springs, or some kind of check valve that might have gotten dirt in it. But, like I said, they both feel the same. Maybe it needs a little more oil in em? Maybe the oil he used sucked?

The 'worked before it quit' part lends some credence to the broken spring idea. If I was going to bet on a mechanical failure of that type or someone (mechanic or not) screwing something up, my money would generally be on the latter. That and..why are both of them the same?


When a leg is compressed, does it always expand to the same place? If, then, you pull it father apart from where it wants to stop on its own accord, what happens?

Loosen the bleed screw. What happens? Air in? Out? Does the fork act any different afterward?

Back to part of your original question...how IS the shock? I'm asking, does it work?

Yeah. They both come back to the top, although, the last two or three inches are slow. And when you push down on them, the first two or three inches feel useless.....Hince to me either springs or oil. But why the drastic change all of a sudden? Could both springs give at the same time? I doubt it!

Rick wrote:Yeah. They both come back to the top, although, the last two or three inches are slow. And when you push down on them, the first two or three inches feel useless.....Hince to me either springs or oil. But why the drastic change all of a sudden? Could both springs give at the same time? I doubt it!

Hey Rick, whatever's wrong, it could be in just one fork since it takes both of 'em to make things work (or not work depending on how you look at it). Think of it this way: if it were both springs, it'd be at least twice as bad (if a broken spring is what's causing your problem).

I had a experience with my YZ forks not too long after I installed them where something didn't seem "balanced" on compression - hard to describe but I lost some stability. I took them back apart and cleaned everything as best I could with brake cleaner (including taking apart the base valve shims and cleaning them well) and it cleared up. Not sure if it was the cleaning but I had read that it doesn't take much fouling to change how those shims work and thus the action. Since were talking rebound I had mentioned one of the check valves in the base valves not opening fully being a possible culprit but I'm not sure if that could impact the recent sagging you get as evidenced by the new wrinkle in your Seal Savers.

Are you sure it's not operater error

kdxandy wrote:Are you sure it's not operater error

See how he is! Teach him to ride. Give him a bike to ride. Help him fix his problems, and baam! He dont need me any more. I'll remember that ANDY!!! Damn Kids!!!

Out of the bike, the forks should fully extend..and quite easily. Part of the easy is quick.

Whatever 'check' is involved for rebound is more for keeping the return passages closed on compression. It's not a valving component in the way of restricting anything.

No big deal to take the base valves out to see what shape they're in. Maybe they're full of junk from the 'service'. Depends on how much taking apart there was at that time. If the insides weren't taken out there's going to be a lot of junk that was dislodged..and it's going to RElodge in the base valve.

The first couple inches doesn't usually offer much resistance. Figure they're 22in/lb springs just for fun. Go press your fist on a bathroom scale and you'll see it doesn't take a huge OOMMPH to push with 40# of force.

There's your couple inches....

The 'real slow' part of the last couple inches of extension doesn't sound right. Usually a fork will just 'boing' to the top. Your much more likely to think 'Gee..there is NO rebound control!' than the other way around.

Shims indeed should be squeaky clean...and they do wear out, too. That's not going to make the forks sit low or be slow on rebound.


Are you sure it's not operator error?

Alright, don't you start on me too! Well, me and my 'Mechanic" are gonna go through them again. I'm hoping we find something wrong. Take the guess work out of it. Ill let ya know. BTW, thanks for your assistance CC. You've been a big, big help. Your OK in my book! I don't care what the others say! I'm sure you don't either.... Thanks to everyone, Rick.

I would bet your rods have unscrewed from your cap on one fork or two.