Cannondale Headshok Fatty SL issue

[hossboss]

Heya y'all.

I picked up an SV2000 recently, and managed to unstick the Headshok after she was sitting for some time. The problem I'm having is when I add pressure to it, it seems to only get a fraction of what I'm putting in - 300psi feels like 30psi. Has anyone had this issue before?

 

[clubby]

The air isn’t going into the air chamber.
Either your shock pump is blocked or more likely the valve on the air chamber is blocked or corroded causing the pump just to pressurise the hose and gauge.
300 psi takes a lot of pumping on suspension units. Try replacing the shraeder core with a new one.
My old fork needed nowhere near those pressures. Does the fork move smoothly enough now it’s unstuck? Are you sure the fork fully extends? Otherwise you might not be filling only a fraction of the air chamber.

Lovely fork when they work. I was lucky, the one I picked up for £50 on eBay was mechanically perfect. If they don’t though …….

 

[Vesatoro]

I had the same issue. The piston was broken and the pressure leaked to the wrong side. There was a pressure of 200psi on both positive and negative sides, causing it to feel like no pressure at all.

 

[hossboss]

The air isn’t going into the air chamber.
Either your shock pump is blocked or more likely the valve on the air chamber is blocked or corroded causing the pump just to pressurise the hose and gauge.
300 psi takes a lot of pumping on suspension units. Try replacing the shraeder core with a new one.
My old fork needed nowhere near those pressures. Does the fork move smoothly enough now it’s unstuck? Are you sure the fork fully extends? Otherwise you might not be filling only a fraction of the air chamber.

Lovely fork when they work. I was lucky, the one I picked up for £50 on eBay was mechanically perfect. If they don’t though …….

The pressure doesn't ramp up as if it's blocked at the valve - I'm adding what feels like the correct pressure. I have a feeling Vesatoro is on the money. Yep, great forks when they work - I had a Super V900 years ago.

 

[hossboss]

I had the same issue. The piston was broken and the pressure leaked to the wrong side. There was a pressure of 200psi on both positive and negative sides, causing it to feel like no pressure at all.

I think this might be the issue! I'll dissect it and see what I find... I'm guessing you replaced the damper unit mate?

 

[clubby]

Bad luck if it is this, good parts aren’t easy to find anymore.

 

[Vesatoro]

Fortunately there a is reproduction part you can buy here https://www.improvepart.com/42/
Of course it can be also the air piston seals that are done...