Shock gas options

[swazi_matt]

There are no suspension guys anywhere near me and my shock needs a service (100+ hours since the last one so guess it is due!)

Anyway I watched it being serviced last time and think I might give it a go, the only hurdle is gassing the shock afterwards
How do you DIY guys do it?
I know some tyre shops offer nitrogen filling, but not sure if they can gas to the required pressure (+- 10 bar I think)

Anywhere else I can consider?

[Jakobi]

Tyre shops won't reach the pressures you need Matt.

Get yourself a lossless chuck and find a fridgey. Dry nitrogen is dry nitrogen. The other option is to simply use air (if you have a compressor that will run up to 10bar), or a shockpump (hand operated).

[webmaster]

"dry air" can be used in a pinch if nitrogen is not available. I bought a nitrogen tank, regulator and a motion pro shock guage/filler - haven't used them in many years. I have Les at LT-Racing do everything for me now...

For DIY - you will need a shock filler/guage (or something similar) along with a needle kit - you need the optional needle for sachs/ohlins.

motion pro parts for nitrogen filling :

http://www.motionpro.com/motorcycle/partno/08-0075

http://www.motionpro.com/motorcycle/partno/08-0072/

You could probably homebrew something together using a "plunger chuck", a gauge and a needle...

jeff

[cbutler]

Try a fire extinguisher service

[Jakobi]

The gauge is a good thing to have, however if your regulator is accurate it shouldn't neccessarily require a 2nd in line gauge. All the Sachs units I've seen use a schrader valve, but the Ohlins and Reigers do require the hyperdermic needle setup.

The other option you have is to contact some dealers (ktm/yamaha/etc) and see if any of them are equipped to regas a shock. Then you simply need to bleed it up yourself and pay them a small fee for the final N2 charge.

[hamilton]

Do yourself a favor and avoid using air. oxygen and oil under pressure = boom
You could buy all the needed tooling for about the same price as a shock service.
Any real dealer should have the equipment to charge the shock for a small fee.
Since I do it all the time, a heavy equipment dealer would have everything except the adapter to fit the shock.

[Jakobi]

I wouldn't consider 145psi high pressure, and air only contains 21% oxygen. While oil and oxygen at certain pressures can go boom, in this scenario very unlikely.

Don't forget, downhill mountain bikes have suspension setups that make our dirt bikes look like toys, and its not uncommon for them to use air in the reservoir at pressures between 125-200psi, and they also recommend using the pressure as a tuning variable.

[swazi_matt]

Thanks. We have fridge and fire extinguisher places here ... real bike dealers ... don't get me started on that!

Air might be a good option for now. I think I need a revalve but with it being so long since the last service whatever testing I do now is not really going to give accurate results. So maybe a service and air gas now, and then maybe take it across the border to South Africa for a nitrogen gas when I know everything is fine

What is the advantage of the no loss chuck? The manual says 150psi +- 25psi so if I use my bike pump that I use for my tubliss and get it close surely a bit here or there will not make a huge difference?

[Jakobi]

You don't need the no loss chuck, but you won't really be able to accurately gauge how much you've put in there. At the pressure and the volume of the ressie the small amount thats lost when uncoupling can be significant, as can the amount lost back into a gauge if you later try to measure it.

You can probably find one at a local store, however if not they can be found on ebay. The other option is to get a shock pump (http://www.chainreactioncycles.com/a...mp/rp-prod7355)

[n_green]

I use similar to what Jake linked to above, a MTB shock pump, comes with gauge and lossless chuck already.

And I used air in the Sachs shock for over 100 hrs and several re-valves, also had air in the Reiger for almost 30hrs now. The Reiger was running N2 after the tuner re-valved it but I opened it for a service and simply changed the oil then re-gassed. With air!

I'm no gun rider but I have a reasonable ability to pick if something is wrong/difference with my bike. No perceptible difference between air and nitrogen that I can tell. I also haven't exploded yet so that's a plus :roll eyes:

My tuner is only 25 mins away and will re-gas for $7, but I don't bother, so take that for what its worth.