MOOSE SHOCK SEALHEAD(lowered the bike.)

[moto9]

I got my sachs shock back together after getting the top eye repaired.

I had a new Moose seal head (parts unlimited #1314-0266) that I wanted to

try which is almost 1/2" taller.

This lowered the bike about an inch, I slid the forks higher in the clamps

to level the bike out....still need seat time to see if I like the changes.

Just wanted to share that this is an alternative way for those that want to

lower the bike some.

 

[Synergy-Seals]

You will notice that your shock will feel spikier sooner in the stroke.....you removed "area" in the shock.

 

[moto9]

I revalved it and I'll have to get some rides in to see if I like the changes.
If I don't I'll switch it back.

 

[PEB]

Does that mean you could raise it with a shorter one? I'd love to raise the bike about an inch.

 

[moto9]

Does that mean you could raise it with a shorter one? I'd love to raise the bike about an inch.

I don't think you'd be able to get a full inch because the linkage would lockout.

 

[twowheels]

The Sachs shocks have at various times in the past used a clevis with an oval insert to locate the lower shock bolt. You can run the bolt in the top location to effectively make the shock shorter, or flip it around and make the ride height taller. None of this affects shock travel, which unfortunately an internal spacer does.

 

[webmaster]

You will notice that your shock will feel spikier sooner in the stroke.....you removed "area" in the shock.

This isn't correct. Removing "volume" from the shock won't make it "spikier sooner in the stroke. Given a properly set piston depth, the nitrogen volume will be the same. You will have a little less fluid in the shock and that's it.. And, as the shock goes through the stroke, the change in nitrogen volume (pressure) will be identical to what it was before the seal head change.

Jeff

 

[webmaster]

Does that mean you could raise it with a shorter one? I'd love to raise the bike about an inch.

Les at LTR used to make shorter links (dog bones) for the quad. These will raise the back end. Check with him as he might still have some lying around.

jeff

 

[GMP]

If the shock is shorter, the linkage starts out its movement at a more progressive point on the curve (higher shaft speed). This is why you have to revalve them when shortened and what I suspect moto9 did. Like Jeff said though the shock volume has nothing to do with it.

 

[moto9]

This isn't correct. Removing "volume" from the shock won't make it "spikier sooner in the stroke. Given a properly set piston depth, the nitrogen volume will be the same. You will have a little less fluid in the shock and that's it.. And, as the shock goes through the stroke, the change in nitrogen volume (pressure) will be identical to what it was before the seal head change.

Jeff

Did I mention I converted the shock over to a bladder.

 

[webmaster]

Did I mention I converted the shock over to a bladder.

Piston or bladder - the concept is the same - you have a little less oil in your shock - no big deal....

jeff

 

[moto9]

Just an update
Got the bike out for a good 4 hour run thru the usual nasty Hawaii single track.

Actually the trails was a pretty good mix of wet/mucky and dry/tacky areas.

There were some good and some bad results.

I'll start with the good
Easier to foot dab, the bike turned quicker and tighter in the tight stuff, overall handling was good.

The bad,
The shock was harsher, I think is was ramping up much quicker, specially on the bigger roots and holes.
The shock also seemed to fade quicker.
I noticed the missing 1'' of ground clearence crossing over logs.

Overall it was a bust, I plan to change the sealhead back to stock, I had the bike working pretty good before so I'll leave it there.

 

[STM Suspension]

I'm a little late, but maybe I'd add a little...

Usually the simple way I lower a bike is to add a spacer inside- easy, cheap, and easily undone. So usually I'll put in a 1 cm spacer just under the seal head and it works great. Make sure you change your preload after this- otherwise you're likely to end up with an extra cm of preload- harsh for sure.

Nitrogen volume is something to note. And for sure you are already a little deeper in the stroke, so getting more into the progressive part.

I have to say that I've lowered a few bikes (my old personal 04 KX250 trail bike among them) and had no issues with a spiky, rough, harsh behavior. For sure I had the proper spring, and for sure I revalved it to suit. But it worked just fine.

There are lots of things that go into tuning a shock- the original poster mentioned that he changed to a bladder set up- and he mentioned it faded quickly. The bladder can make it feel different. As was pointed out, perhaps the bladder has a smaller nitrogen volume then the previous floating piston- And I have to ask why it's fading quickly with fresh fluid in it...

We use something like a 2.5 in rear dirt shocks- changes viscosity less when it gets hot. But fresh fluid shouldn't be fading anytime shortly after a rebuild.