It's nice having it sprung heavier. The new valving is a trip. I have new valving in the forks but not the shock. I feel the bumps I already went over with the back wheel. I have to set my sag yet and play with the compression dampening in the front yet. Yesterday I went to the farm and rode for an hour or so. The front end got a little bouncy on me a few times. Once was when I was climbing up a 45 degree hillside over mossy rocks and I wasn't shifting my weight forward just far enough and I blipped the throttle a little more while going up over a 6" rock and I popped a wheelie and the front end went where it wanted to and bounced a few times and I stayed up but ended in the bushes. After that I did that hill 4 or 5 more times a little better prepared and it went fine.

On a side note, with my big, fat butt on it as a 250, I couldn't ride it hard enough. Now that it has an increase of displacement, lowered gearing, and other mods, it has enough torque now that I need to watch it a little in the tight stuff. I wasn't used to that. Very pleasant surprise.

Anyway, I found the front wheel responds to the ground great. It keeps its line and stays in control a LOT better than it did before with the OEM suspension. I went all over all kinds of stuff at all kinds of speeds and sure as hell is a lot different.

So what do you do about bounciness? Is that controlled with the fluid level?

 

That is what you fixed... Turn the bypass screws in all the way if you have to. If that is not enough you need to restack your valves.....

The glory of having those newfangled valves is you can tune them. I started out at 10 high speed and 10 low speed. Its fine for me with the bypass screw at 11 clicks. Could go in a few more in but its cold out right now and I am leaving it a little soft bot front and rear.

All I can say is the bumps that threw me or jarred my fame are now just uneventful including the 3 track crossing by work.

Once you get the front and rear matched, its a new world. Keep messing width the sag it makes a big difference.

David

I have been riding more too, Curbs and medians, I just drive right over them and the suspension does its job. When I screw up a wheelie and slam the front end down it does better too.

 

Wouldn't that be a rebound issue though? We control compression with the valving and the bypass screw. What do we do about rebound? I though that all we could do for that is manipulate fluid viscosity and level?

 

Yes, unfortunately we can't get into the rebound stack on the fork. Rick at Cogent Dynamics tore into his KLX fork and reshimmed and added an adjuster in the top cap for rebound...but alas...he works at a suspension designer/manufacturer and has a few more resources...LOL! Changing oil viscosity is the only tuning element we have on the fork. Fork oil level will only affect bottomout, so that's more of a compression/end-of-travel adjustment. That said, I've not had an issue with the rebound on my fork. It was nice in the rear shock, because you could revalve the rebound and compression, and of course there are two external adjusters. Too bad the fork didn't have it.

 

The screw is just a bypass. It bypasses for compression AND rebound. Its open both ways when you Unscrew it. SO it effects both compression and rebound.

Turn them all the way in and see if there is a difference.

Rebound valve is the same as compression. It has a one way valve for return. Having the bypass screw open allows flow both ways. Any oil be it compression or rebound will flow freely through the bypass screw regardless where its located. Do I make any sense at all?

And what HE said. Thicker oil will make it rebound less but will affect compression too.

ALSO I have found making adjustments on one end of the bike effect the other. Try your rear rebound at about 4 to 5 clicks from closed.

 

OK, I do not claim full knowledge on this, but I'm not so sure the rebound and compression in the fork are actually controlled by the bleed screw in the compression valve unit. I wish I'd paid more attention when I had mine apart to look more closely. The rebound circuit/valving is contained within the cylinder unit assembly that rides above the compression cylinder valve assembly...correct? I think that oil flow to the rebound circuit can flow into and around the push rod and through the rebound circuit independent of the flow of oil controlled by the compression valve bleed screw...doesn't it?

Rick at Cogent Dynamics mentioned nothing to me about an interaction between the compression valve bleed screw and the rebound circuit. He used an adjuster rod going from the top cap into his reshimmed rebound circuit to control the rebound. Like I said, if I knew there was going to be a test, I think I could have inspected the components more closely, but even looking at the pics in the service manual, I'm leaning toward the issue of the compression valve bleed screw only affecting the compression stack. Again, I don't claim this to be total fact at this point. It would be great to see a flow chart for the old 43mm KYB fork we have, but I don't know where that would exist. Some of you guys have had your forks apart much more recently than me, so you may know better.

 

Awesome! Thanks for the info!! I'll try that.

 

OK, leme try again.

The bleeder screw or compression screw is a bypass. Oil can flow in or out, back or forth etc. When the valve is open. Close the "compression" screw and NO oil flows. I tested this using the oral low pressure mode. I blew in it. Closed is closed. No oil bypass in either direction and open is open. Flow the same amount in either direction although limited to how far the screw is open.

For the REBOUND damper valve, it is basically the same as the compression valve except the oil flows the other way. One way it flows freely (compression) the other way (rebound) It MUST flow through the rebound valve which slows the flow down so you are not riding a pogo stick.

Back to the bleeder valve screw. IF its open all the way, oil can flow both ways. It can flow through the bleeder under rebound instead of through the rebound valve. Oil is also going to want to flow through this bleeder because the rebound valve is restricting the flow.

I think FD got it. Alfred you on board? Ya don't have to agree, but do you understand what the heck I am trying to say?

I think I figured this out when I had it apart. I THOUGHT the "compression adjuster" put tension on the shim pack or something. It does not, its just a bypass. It DOES work on compression. At 11 clicks I get a smoother ride than at 5 clicks from closed. The rougher ride could be from both compression and rebound.

David who should be working instead of screwing around on the puter.



EDIT sitting here thinking.......

When the forks are moving apart or spring is getting longer or .... The oil can flow through the compression valve freely through the one way or check valve part on top of the valve. SO if the screw is open it may not matter. Go ahead, smack me.

David

 

I called your boss, David, and he reminded me of Donald Trump when he said..."Ya fired!"

Yeah, I'm still not getting an absolutely clear picture here. I spent all my attention over a year ago on the compression valve, because the rebound circuit was inaccessible. I wish I had been more curious at the time. The rear shock is like a no-brainer. It's funny how people are usually more afraid of getting into the rear shock, but ours is a real simpleton to disassemble and work on...and to understand the precise function of everything.

 

I'll tinker with it when I get time. I got myself waist deep in another suspension project. I'm fitting 43mm KYB forks off a '91 KX500 on my '07 KLR. It almost bolted right on. I had to swap the spindles and make a few spacers. This is going to rock.

Then I'll need to do this adjustment tinkering with 2 bikes.