Front suspension input requested...

Haywood · 06-23-2004, 12:46 AM

Was out this weekend riding the 74 out by Palm Desert. The upper section of the 74 is older asphalt and has lots of seams perpendicular to the direction of traffic. It's the kind of pattern that creates a front-rear pitching effect.

In a couple of corners I noticed the front end had a tendancy to 'push' a bit. I've got static sag set and some basic setup from a reputable shop (Lee's), so I know I have a decent baseline setup. And I'm comfortable with that baseline setup, it's good.

I can't really tell if it was rebounding too fast, or if it was to slow. Any ideas/questions are welcome. I'd like to know if I can figure out what I need to take a look at at the front end. I also don't quite know what to expect from compression adjustments. Preload is set right, so I'm leaning towards either the rebound, or the compression (prolly wont touch it).

Ernie · 06-23-2004, 1:12 AM

Push as in chatter or push as in slide? Chatter is usually lack of rebound damping. Slide may be too much and fork packing down.

Dont forget the bike is big and heavy thus more prone to push the front. The only suggestion I would make is try one thing only. And dont be afraid to move the rebound several clicks, JUST KEEP TRACK IN WRITING so you know what you did.

Ernie

Haywood · 06-23-2004, 10:27 AM

Quote:

Originally Posted by Ernie

Push as in chatter or push as in slide? Chatter is usually lack of rebound damping. Slide may be too much and fork packing down.

Dont forget the bike is big and heavy thus more prone to push the front. The only suggestion I would make is try one thing only. And dont be afraid to move the rebound several clicks, JUST KEEP TRACK IN WRITING so you know what you did.

Ernie

It was defenitly more of a push than a slide. It felt like the fork was 'cavitating' on rebound. I'll start with a bit more rebound damping.

Thank you.

Ernie · 06-23-2004, 11:41 AM

Ok, if it is chattering, definitely more rebound.

Ernie

ccwilli3 · 06-23-2004, 11:46 AM

not enough high speed flow (too much high speed damping?) so it packs up?? dunno, just throwing it out there...

Ernie · 06-23-2004, 1:10 PM

Good call. The stock HMAS valves are not that great for high speed damping, they tend to almost lock up. So if the roadway has "high speed bumps" meaning bumps that accellerate the wheel up and down quickly, like a brick or a pothole, the high speed compression damping can not handle it and the fork almost locks up. The only thing you can do with that is revalve, external adjustments wont help.

Ernie

Haywood · 06-23-2004, 6:43 PM

Quote:

Originally Posted by Ernie

Good call. The stock HMAS valves are not that great for high speed damping, they tend to almost lock up. So if the roadway has "high speed bumps" meaning bumps that accellerate the wheel up and down quickly, like a brick or a pothole, the high speed compression damping can not handle it and the fork almost locks up. The only thing you can do with that is revalve, external adjustments wont help.

Ernie

Well, I'm going to start with the rebound damping. But the packing seems a little more accurate to the feeling I got.

If there's no change (or its worse) with the rebound, I guess it'd have to be the high-speed compression.

The corners were fairly quick with the seams seperated about every seven feet or so. I was suprised the rear felt as planted as it did, given that I only weigh in at about 140lbs or so. I was quite suprised at the rear. The front did much better than I expected, so I'm happy. Just want to try and iron out that chatter.

Thanks again for the info.