Glottis

Hi,

I have a Giant Cypress which has a suspension fork. I want to make the suspension as stiff as possible. Please see attachment to see how it looks.

Am I right in thinking that it's possible to tune it? Do I need some special tool to do it?

Thank you!

bikinfool

All I can tell from your photo is that it's an SR Suntour fork, whose products at that end of the spectrum barely justifies the term "suspension", and it likely has little or no adjustability or available spare parts/springs (or even information available from Suntour, although you might look at SR Suntour's site for a manual...).

Glottis

Yes I know it's a low end fork. The difference between the right and left plastic caps (see attachment in 1st post) made me hope that some adjustment is possible.

dougtoma01

I just restored a GT mountain bike for my son. It had RoxShocks and under the caps was a hole that you could put in a inflation attachment for like a football and adjust air pressure to adjust stiffness. Not sure of yours has the same capability. Also, reading up on those type of air inflation systems, the valves go bad over time, so yours may not hold the pressure. In that case they would need to be rebuilt or replaced. Best regards, Doug

dedhed

Most likely that is not adjustable at all. Lower end unit. If it has an adjustable fork, I'd be surprised. Usually if adjustment is possible you'd see arrrows and +/- or something to indicate how to adjust. It's not an air fork.

Glottis

Thanks for the help. At least now I know I can do nothing about it.

I was thinking of blocking its movement with a clamp or something. Do you think it's safe to do that?

LarDasse74

It is very likely that there is a way to disassemble your fork. If this is the case, to make it completely rigid you need only replace the springs with similarly sized wooden dowel from the hardware store.

You may be able to use a clamp but this is likely to damage the fork and result in making your fork just work more crappily, not completely limiting its movement.

ALso, you can probably get a good quality rigid fork for ~$40 from the LBS, or find a $20 donor bike at a garage sale or something.

Stiffening a suspension fork is a good way to make a bike better for riding roads or smoother trails.

dabac

+1

Might be elastomer(= rubber cushions) instead of springs though. Otherwise far better than clamping.

+1

and worst case, you might crimp the legs, causing a failure.
If you really want to overdo it, you should try to set the fork somewhere closer to mid-travel than fully extended, which would require something more than only replacing suspension elements with wooden dowels.

One way of "rigidifying" a sus fork I'm a bit curious to try would be to open it up, clean it out, remove some internal components (if needed), and then simply pour something like polyester resin into it. It should, theoretically, let you set ride height as well as blocking out rebound in one go. It'd add some weight, but it sounds simple enough.

Or if you're really lucky, find a fork from someone who've gone from rigid to suspension.
Bear in mind though, that different sizes and build standards can make straight swaps more difficult than you'd first thought. Crude as it is, turning a sus fork rigid may be a preferable option due to this, on a low-end bike.


Indeed.