Washboard

[motrock93b]

I finally had a chance to test my CRF 250X fork revalve and am pleased they are working more to my liking. I've been trying to reduce harshness on square edges, and I'm pretty happy, but would like to make them smoother over tight, hardpacked washboard sections. I've softened the BV HS as well as the MV comp without changing float. Would increasing midvalve float help, say from .15 to .25 or so? Also, I know it's not popular, but what about a three stage stack to delay immediately blowing into the stiffer high speed base valve stack while hitting these shallow yet harsh sections? I'm not doing any moto with this bike, and am just trying to smooth trails and singletrack with no big jumping.

[mog]

It's most likely a rebound issue

[motrock93b]

Lighten the rebound?

[mog]

Yes

[motrock93b]

Thanks, Mog.

 

 

[GP]

Sometimes it's confusing between comp and rebound issues, especially if your just getting into tuning. Try using an iPhone or video camera on the side of the trail near the obstacle of interest and you will see exactly what the problem is.

[MetricMuscle]

Did you post your shim stack somewhere?

 

[nailit69]

Not that you might not have other issues but I run the tubliss setup and 10-15psi and untouched forks and can devour washboard and maintain excellent traction in excess of 75mph on my XR600.  Maybe your tire pressure is too high?

[motrock93b]

Not that you might not have other issues but I run the tubliss setup and 10-15psi and untouched forks and can devour washboard and maintain excellent traction in excess of 75mph on my XR600.  Maybe your tire pressure is too high?

I run 12-14 psi. Today's test with fully open rebound clickers seemed to improve things. I still may make some valving changes, and am definitely making these forks better for my needs.

[heart_of_darkness]

And have the fork compression clickers fully open too.  And adjust the shock to fully soft on both high and low speed compression, and the shock rebound sufficiently fast.

[motrock93b]

And have the fork compression clickers fully open too.  And adjust the shock to fully soft on both high and low speed compression, and the shock rebound sufficiently fast.

I have tested those settings, and noticed improvement. The bike works well, but I think it can be improved for my riding by further softening front and rear.

[numroe]

On 17/04/2017 at 10:34 AM, motrock93b said:

I've been trying to reduce harshness on square edges, and I'm pretty happy, but would like to make them smoother over tight, hardpacked washboard sections. I've softened the BV HS as well as the MV comp without changing float. Would increasing midvalve float help, say from .15 to .25 or so?

I don't know the sane range of mid comp float for the Showa forks, but in my experience with KYB CC forks, a wider float (like 0.2 vs 0.3mm) makes a huge difference to the amount of feedback over hard chattery bumps.

Imagine riding a clay track that was rotary disced when soft then baked rock hard in the hot sun for a few days. On that kind of dirt, tight mid float is a wrist jarring nightmare.

But for hitting sharp large bumps very fast, a tight float can work great. I think because the damping forces begin sooner.

[motrock93b]

I don't know the sane range of mid comp float for the Showa forks, but in my experience with KYB CC forks, a wider float (like 0.2 vs 0.3mm) makes a huge difference to the amount of feedback over hard chattery bumps.
Imagine riding a clay track that was rotary disced when soft then baked rock hard in the hot sun for a few days. On that kind of dirt, tight mid float is a wrist jarring nightmare.
But for hitting sharp large bumps very fast, a tight float can work great. I think because the damping forces begin sooner.

Thanks, Numroe, more float is on the menue for the next revalve.