How to: Service 2008 Steering Damper (lots of pics)

[armourbl]

The stack is a compression/rebound stack. With the bars centered/wheel pointing straight ahead is the null position. Turn left or right and the shaft extends out of the cylinder (comp) and return the wheel to pointing staight the shaft enters the cylinder (reb). This occurs in both directions.

The reason the stacks are different is the input that causes the wheel to move from pointing straight (typically an input from the track/ground) is at a much higher frequency than the response (rider returning the bars to straight).

Great work with the write up.

That is a much better description of what I meant to say. Thanks. I wasn't talking about left to right necessarily, but away from center to return to center.

ben

[Doofosmitch]

Just did mine, i had about 10mm of oil in mine, HOW SAD!! Hopefully now it will actually do something. I put belray 5w in mine.

Thanks for the write-up. made my life easier ?

Any suggestions on how many clicks would be good for "sugar sand" (lots of breaking bumps and accel bumps)

[MRW]

Any suggestions on how many clicks would be good for "sugar sand" (lots of breaking bumps and accel bumps)

Ahhhhh, Bithlo:ride: ......see my avatar.

I have no idea about how many clicks though as I have an 05 crf450.

[jethro450]

Here's my update:

I followed this thread and revalved my damper back in January. I also put the heaviest oil I could find back in it - which happened to be Belray 80W two-stroke tranny oil. When I put it back on the bike, with the bike on a stand and no weight on the front end, the bars very slowly make their way to an end point. Before they would just flop either way, before there was hardly any oil in the damper too.

Well after months of snow snow snow and no riding (I did ride a converted snow bike, it was sweet!), I finally had a chance to go ride.

I rode out in the desert of Utah (Jericho) - fast paced whooped out sandy/gravelish trails. I gotta say, this revalve and thick oil made a huge difference! I have it adjusted right in the middle which is 10 clicks out.

It's still no SCOTTS, but it is enough of an improvement that I won't bother looking for a SCOTTS for a little while. Large hits can still knock you out of whack whereas a SCOTTS would hold you straight (I've ridden with a scotts damper before so I can compare).

In the whoops you may still get a little swap (no swap at all with a scotts) but it brings it back pretty quick.

So yes, it helps, and no, it's not a Scotts -but for me it will work for a while.

Oh ya, the biggest help would be to RIDE more than once every four months! I was so outta shape it was ridiculous. I used to race the pro class in the desert and have placed rather well a few times (top five), but that was back when I rode twice a week on the regular. Being in shape and able to muscle your way through whoops helps with the bar swap factor in a big way. Once you are tired, bar swap sets in, and if you don't have help from a damper your destiny will soon be ground-ski-air-ground-ski-ground-ski.... you get the point.

[armourbl]

Thanks for posting back on your results. I'm going to through a heavier oil in mine now. Been on the fence about getting a GPR because more and more I find myself in situations that I could benefit greatly from it on the track. My trail bike has one and it makes riding so much more enjoyable.

I'll tinker more with the stock unit until I can save up enough money for the GPR.

ben

[Thump3r450]

I wish I could add one to my 07.

[K-dogg]

I wish I could add one to my 07.

You can.

MXBONZ

[Thump3r450]

Thanks, does it stiffen it up quite a bit or does the damper need heavier oil?

[turboandy]

Thump3r450 sent you a pm

[turboandy]

I have a complete set of 08 clamps with the dampner, steering stem and lower bearing with the adapter to install them on a 05 thru 07. Pm me if interested.

[shawneemac]

im going to go try a rebuild right now!

[aedwards07]

Just got done rebuilding mine.Was bored today and read this so decided why not.I had mine redone at the same time I got my suspension revalved and the oil didnt look too too bad with 35 hours on it.It will dirty but not black.Threw some 5WT fork oil in it and called it good.Works better now for sure.

[shawneemac]

thanks for the post! this helped allot!

[kwoody51]

Did this rebuild last night, pretty straight forward.

Couple of questions though. It seems like there is positive pressure on the shaft and thus it wants to extend to full length. Did I put in too much oil or is this normal?

Also I removed the valve stack and in the process a little bit of the threads from the shaft turned up in removing the nut. I assume this is unavoidable as they peen the shaft to hold the nut in place?

Thanks!

[armourbl]

Sounds to me like you got it right. As long as the shaft if moving the full range without restriction, then you didn't put too much oil in. The peening is unavoidable, and it is light on these threads, so no harm. Most will grind of the peened area to prevent the thread turning. In your case, just sand the ends of the threads to knock off any jagged edges.

ben

[theDogger]

Ya you have to grid the peen off you are luck that you did not damage the post. If you were working on your fork you would have snapped the post off! Also you can't get too much oil in the body. It will correct itself when you are bleeding it to the proper level. I would worry if it doesn't extend all the way!

theDogger

[kwoody51]

Ya you have to grid the peen off you are luck that you did not damage the post. If you were working on your fork you would have snapped the post off! Also you can't get too much oil in the body. It will correct itself when you are bleeding it to the proper level. I would worry if it doesn't extend all the way!

theDogger

Yeah I vaguely remembered needing to file the peening off after I took the nut off. Guess this is notice to all the others pulling their valve stack.... file the peening prior to pulling the nut.

The shaft travels through it's entire motion no issues there. Just didn't notice the shaft wanting to extend itself out on it's own before I took it apart.

I figured that any excess oil would either come out, or flow back into the area that is under the springed piston.

[armourbl]

Yeah I vaguely remembered needing to file the peening off after I took the nut off. Guess this is notice to all the others pulling their valve stack.... file the peening prior to pulling the nut.

The shaft travels through it's entire motion no issues there. Just didn't notice the shaft wanting to extend itself out on it's own before I took it apart.

I figured that any excess oil would either come out, or flow back into the area that is under the springed piston.

Unfortunately, I doubt it was put together correctly at the factory. Mine barely had any oil at all in it stock.

ben

[Thumpy Thumperton]

Is there any way to shuffle the existing shim stack in a way that would add dampening to the HPSD? or is the heavier oil the way t o go?

[kwoody51]

Yeah I vaguely remembered needing to file the peening off after I took the nut off. Guess this is notice to all the others pulling their valve stack.... file the peening prior to pulling the nut.

The shaft travels through it's entire motion no issues there. Just didn't notice the shaft wanting to extend itself out on it's own before I took it apart.

I figured that any excess oil would either come out, or flow back into the area that is under the springed piston.

Just for future tinkers, you don't have to pull the small clip out if you just want to swap some of the oil or get at the shim stack. You can pull just the main clip around the shaft and take that out.

I put in some 15w 50, felt a little heavy so I pulled the shaft and shim stack sucked out some of the oil and put some 10w 30 in there. Feels about right now. I can run it full open and not feel it at all, or full hard and I it feels like it doing something.