X fusion sweep problem

outtacontrol

outtacontrol

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Hi, my fork has stopped using full travel. It's set to 150mm but regardless of how much pressure it's running, cant use the last 30-40mm of travel.
It is very smooth in its action so didnt notice initially. Usually means oil is somewhere it's not supposed to be??

Haven't done much with forks internally before so any help appreciated.
 
Warp

Warp

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outtacontrol said:
Hi, my fork has stopped using full travel. It's set to 150mm but regardless of how much pressure it's running, cant use the last 30-40mm of travel.
It is very smooth in its action so didnt notice initially. Usually means oil is somewhere it's not supposed to be??

Haven't done much with forks internally before so any help appreciated.
Click to expand...
Have you tried to take out all of the air and measure travel? I'm assuming you had.

So, yeah... probably oil migrating from the damper to the lowers.

But first you could try by inserting a small zip tie between the wipers and the stanchion and see if you have some air in the lowers.
IF that doesn't work, they may need service/repair.

If under warranty contact DIYmtb.com.au
 
outtacontrol

outtacontrol

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So no one else has had this. I have heard of a couple losing their lockout and google tells of some on mtbr that had the top of the damper leg explode after a heavy hit. These guys all reported a loss of travel in the leadup so may be related?
 
outtacontrol

outtacontrol

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No warranty :-(

Turns out there was too much oil in the damper. Here's the catch, the damper has never been open???
I know it was delivered like this because loss of travel only started a week or two ago.

So the million dollar question is, Where did the oil come from??
 
outtacontrol

outtacontrol

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bikeyoulongtime said:
interesting! There is 15cc of oil in the lowers of each leg, maybe some migrated into the damper through a slightly busted seal.

Gonna pull my sweeps apart soon and replace seals (ready to sell... to fund a roughcut sweep :D ), I'll have a close look at what could have gone on. This thread is also pretty useful:

http://forums.mtbr.com/shocks-suspension/official-xfusion-rl2-fork-service-tuning-thread-910996.html
Click to expand...
Funny you should say that. Just found that thread, fast forward to page 5 onwards and every second post has the same issue as mine. Some even eventuated with the damper exploding after a big hit. All reported a loss of travel.

After reading all of this thread, X Fusion would have to be aware of this issue, so to get knocked back for warranty leaves me with a shitty taste in my mouth...

http://forums.mtbr.com/shocks-suspe...-rl2-fork-service-tuning-thread-910996-5.html
 
B

BKMad

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I've just noticed this happening to my sweep as well. Its only started to loose travel since I last did a lowers service. I'm guessing that this is a progressive thing in that it sucks up a bit of oil from the lowers, add more oil during a lowers service and it then sucks up a bit more. By the time its had a few lowers services, its got too much oil in the damper and its loosing travel. Its pretty easy to service the damper so that should fix it. I agree its not ideal though.

It not isolated to x fusion either: http://forums.mtbr.com/shocks-suspension/long-term-report-rockshox-pike-charger-damper-961615.html
 
D

DJR

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With the design of that damper it might be possible for oil to weep down the rebound shaft and past the seal if the bike is put upside down often. Or maybe from the top also. Not sure where that might happen. Seems pretty simple to open the cart up, I'm due for a cart service (going to change shimstack while there) and have the RSF to put back in.

Potentially you could get the top of the cart off syringe the extra oil out.
 
outtacontrol

outtacontrol

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Duncan from DIYMTB has been very helpful and through communications with X Fusion in the states it has become apparent that X Fusion are aware of the issue, alrhough seemingly unaware of the cause?
Big thumbs up for Duncan who has rectified under warranty.
 
Rhys_

Rhys_

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My old Mattoc had a similar issue, just nowhere near this bad. You could try running less oil in the damper side lower and/or try a thicker oil
 
D

DJR

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I did a damper service today and I reckon the problem is the way the damper seals inside the stanchion. There is just an o-ring separating the lowers from the cartridge. Add a little positive pressure from the lowers into the cart with the forks upside down and you will get a bit of oil coming across. Thats the most obvious way but there might be another way.

Technically you could pop the top off the damper side and pull up the cartridge a little to expose the fluid and then drain 10 or 15mL out with a syringe then screw the top cap back on correctly. But if you're gonna go to that trouble you might as well empty all the fluid and replace.

The method I thought would work to do a damper service without taking apart the air side and removing the lowers worked just fine too. While I was there I did the lower compression stack shim mod so I need to go ride it and test that out to see if it has helped with the small bump stiction
 
B

BKMad

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I did a damper service on mine over the weekend and I'm back to getting full travel on the bigger hits. When I unscrewed the top cap on the damper side there was a hiss of air so it had definitely sucked up some oil from the lowers and pressurised the damper. I got 3 lower services in before it started losing travel so it was probably due a damper service anyway. Like I said before, its not ideal, but it is an easy fix.
 
9

99_FGT

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Checked mine, don't appear to have the issue (thanks Darren). Mine have done very little work, but I'd been holding off putting them up for sale as I wasn't sure if mine had the issue or not.
Al..
 
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