All 2st sachs pogo shock

midway through its last 2 rides my sachs shock has turned into a pogo stick-lost all compression damping and just bounces-for a few minutes and then comes good. no oil leaks everything looks ok but its like riding on a trampoline and dodgy as all hell! bikes a year old, is it just time for a shock service? its copped a bit of a hammering but old showa shock went 2 years and was still going strong(admittedly i push my wr300 much harder than old crf450x). what does a service entail-just oil and gas change?

I'm guessing you had the nitrogen leaked out.
I had a similar problem with an XR400, I just pumped it up with regular air (78% Nitrogen) all was fine after that. Find out how much pressure it should be.

Regards, Bart

is that what gas is in there originally-just compressed air? thought it would be some flash gas that will be expensive to replace. how long usually until you blokes get your suspension serviced for just basic trail riding and very occasional mx riding? didnt wanna touch my forks till i do a seal cos im cheap but still havnt had a leaking fork seal yet(run seal savers and they seem to be working). KYB lasting much better than old showa(3-4 seals in less than 2 years!)