fork trouble

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fork trouble

Postby brutusobrien84 » Mon Oct 21, 2013 8:32 pm

hi everyone. iv noticed a bit of a problem with my front fork. its a rock shox recon and its about 18 months old. its been used quite regularly 2to4 times a week. i really look after the bike, clean it after every ride and always clean and lube the stanchions. but lately iv noticed that when i apply pressure first the fork sticks, i have to give it a good bounce before it works, then it works fine until its been idle for a little bit.
so im wondering has anyone else had this problem? or is it something that i shouldnt be that worried about. thanks !
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by BNA » Mon Oct 21, 2013 8:58 pm

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Re: fork trouble

Postby Duck! » Mon Oct 21, 2013 8:58 pm

Air or coil spring?
I had a thought, but it got run over as it crossed my mind.
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Re: fork trouble

Postby brutusobrien84 » Tue Oct 22, 2013 5:13 am

Coil spring.
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Re: fork trouble

Postby FuzzyDropbear » Tue Oct 22, 2013 10:25 am

How long since the bottoms have been serviced?

Sounds to me like there's no, or little grease in the bottoms, causing the seal to stick a bit. That's what happens to my coil forks after a while anyway. The grease is gradually used up as the forks are compressed and rebound again (think the lube you wipe off the stanchions), so it needs a top up every so many hours (the service manual for your forks should give you this info).

Not a huge job as long as you have a few basic tools and some grease.
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Re: fork trouble

Postby Duck! » Tue Oct 22, 2013 12:47 pm

Ensure you use a non-lithium-based grease, otherwise you run the risk of an electrolytic reaction with the magnesium lower casting.

While you're pulling it all apart it's worth giving the rebound/lockout side a service too, replacing the internal seals & oil.
I had a thought, but it got run over as it crossed my mind.
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Re: fork trouble

Postby brutusobrien84 » Tue Oct 22, 2013 1:19 pm

It had a full service last Xmas. So if that is grease is the problem it's well dry. Ok sounds good. Thanks for your replies!!
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Re: fork trouble

Postby brutusobrien84 » Tue Oct 22, 2013 8:24 pm

by the way. is there a particular brand of non lithium grease? is it something i can get in my lbs? also will i need oil for the forks? i gave it quick google and a look on srams fork guide and it seems i need oil for the bottoms.
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Re: fork trouble

Postby Mulger bill » Tue Oct 22, 2013 8:50 pm

I've always been happy with Slick Honey so haven't researched alternatives, I'm sure there's some out there.
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Re: fork trouble

Postby Duck! » Tue Oct 22, 2013 9:14 pm

Any automotive shop should have a non-lithium grease in the range somewhere. You'll also be able to find fork oil there too.

If you're only servicing the spring side you won't need oil, but you definitely will if you dig into the rebound/lockout side. You'll need two "weights" (densities) of oil, 15wt (heavier & stickier) for lubricating the o-rings, and 5wt (lighter & better-flowing) for the oil bath that does the rebound damping & compression locking.
I had a thought, but it got run over as it crossed my mind.
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Re: fork trouble

Postby brutusobrien84 » Tue Nov 05, 2013 7:52 pm

hi again. i finally got the time time to service the forks. there was barely any oil left in them. i followed srams instructions to a tee and all went well. until i was refilling it with oil and the tip of the syringe broke. it was still ok to measure oil, but harder to get the oil in the fork.i probably did spill a bit but i didn't think it was much. the thing is when i put the forks back together, they still stick. if anything even worse than they did before hand… would this be because of that little bit oil that was spilled??
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Re: fork trouble

Postby Duck! » Tue Nov 05, 2013 8:04 pm

Here's a thought.... Is your lockout functioning correctly? I came across a Recon a few years ago where the lockout wasn't working, but the fork wasn't compressing freely either. What had happened was there was breakage in the damper cartridge, resulting in limited oil flow. The compression damper/lockout cartridge has a rod down the guts of it to connect the dial (or remote atachment if applicable) at the top to a "tap" at the base, which shuts off oil flow when in the locked position. On top of the tap is a vane which fits into a slot in the end of the twist rod; this had broken on the fork I encountered, so the tap was stuck in a partially-open position. The restricted oil flow slowed the compression rate of the fork, but would not allow it to fully lock either.

Could be worth a look.
I had a thought, but it got run over as it crossed my mind.
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Re: fork trouble

Postby DarrylH » Wed Nov 06, 2013 7:03 pm

I've also had problems with the lockout not functioning correctly but it was because the lockout mechanism had partly unscrewed from the cap. If I remember correctly, the cap screws into the fork clockwise but the lockout screws anticlockwise into the cap. As the lockout was fairly tight in the fork, as I screwed the cap in, it was unscrewing the lockout.
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