Issues with Fox rear shock

Sev101

I have a feeling I know the answer to this already but just in case am missing something obvious!

I have a fox float r on a marin rift zone 06 and I am hitting the bottom of the travel on the rear shock when I sit on the bike. I posted a few days ago and nicklouse kindly gave me some tips to make sure I had everything set correctly. I have tried increasing the amount of air in the rear shock and managed to get it up to 200 psi but when I sat on it the travel went straight down to the bottom and when I reattached the pump it read 150 psi again which is what it said before I started this malarky!

Basic question is do I need new seals in the shock and if so where do I get them from?

Cheers ears!

nicklouse

add more air!

yes the air drops when you attach the pump.

attach the shock pump and pump to 200 psi. disconect. Now reconnect. what does the pressure now read? 150? pump to 200 disconect and reattach what does it read 150? this in NORMAL.

If 200 is causing the bike to bottom out then you need more air in the can.

Sev101

thanks will give it a go - I was struggling to get it to pump up to the 200 mark - it only once allowed me to do this other than that it would not take more air into it or at least it did not read any different when the pump was connected.

I wil try it agian later and let you know how I get on

Thanks for the advice

nicklouse

you do have a shock pump dont you. 300psi is easy with the correct pump.

Sev101

yes I do which will do up to 300 psi wil try again tonight

zippyd

I'm having problems with my Fox Rear Shock too, that sound not disimilar!

To get even 50% sag on my Float R (Marin Rift Zone 2007), I've had to pump the shock up to 300PSI! Having tried other Marins in store, it should have required 150 - 180 PSI max for my weight and height.

I felt this wasn't right and took the bike back to Edinburgh BC in Newcastle, who stripped the shock out and sent it back to Mojo for a Factory Service as it's less than 6 months old.

Got the bike back today, with a repair note saying Mojo had replaced the seals and factory serviced it and it should be working fine.

However, I get the bike home and thought it would be a good idea to check it., Check the shock pressure, 170PSI, sling my leg over and sit on the seat gently and it settles down to approx 70% sag, not the recommended 30%!!!!!

This gets me thinking have Mojo actually done anything, as if anything it seems worse than before! Guess I'll be back to EBC on Saturday, after a phone call tomorrow.

However, this got me to thinking, is this a common problem with Fox Rear Shocks?

Rockhopper

It won't loose 50psi simply by unplugging the shock pump will it? Mine certainly doesnt. It drops by about 5 psi if that.

toasty

No, but attaching the shock pump next time will lose the 50psi. The chamber is very small, adding the pump to the top makes the chamber bigger, hence lower pressure.

You shouldn't lose anything disconnecting, it might make a sound like it is, this is just the pressure inside the top of the pump emptying out. Not the air in the shock (assuming you're using the shock pump correctly).

nicklouse

zippyd
so what is your weight? and what is the stroke of the shock?

skyliner

Have you got a shock pump with a long fixing for the Schraeder valve?
It could be a Manitou specific pump, and it'll lose a lot of pressure as you remove it.
Trek AKA Wrench Force pumps tend to do this.

Thewaylander

Personally i'd get teh shock checked out, there is known issues on some fox shocks for there seals from factory.. house mates rear float actually inverted and sucked up all his travel and didnt give it back, that was after a week

nicklouse

Thewaylander
that is the lock down issue that is know about.

Thewaylander

coolio Nick, been a few months since it poped, couldnt rememeber exactl how it happened was to a friends Kona.

still get it checked out though. not worth trashing a shock if summat is wrong if you can get fixed easy enough

zippyd

Stroke legnth, Hmmm? It's a standard factory specced 2007 Float R, so I guess 2", and I weigh about 97 Kg.

Weather has been s**t here today and I've been at work, so I've not had time to play around with the shock, trying increased pressures and the like to see what effect this has.

However, as I said initially, having tried a similar 2008 Marin with the 2008 version of the shock to see what sort of sag was occurring, at 170 PSI it was pretty much spot on at 30-35%, so I'm thinking mine should be the same (allowing for slight differences between individual shocks).

zippyd

Well, having had the bike back to my LBS (Edinburgh BC in Newcastle), they agree that after the shock being factory serviced by Mojo if it still ain't fixed, something ain't right.

They've taken it up with Marin, who have agreed to replace the shock under warranty (yipee) The old shock is coming out tomorrow and the new one fitted when it comes from Marin (hopefully not too long as knowing my luck, we'll have lovely warm weekend whilst the bikes out of action and I'll get it back when it statrts to rain again).

In the meantime it's back to my old school, steel Marin Bear Valley.

I'll let you know how it goes!