As above.

My rockshox Sektor solo air 2015 will only use 115mm of travel. Nothing seems to help. Even if I have only a few psi in the fork, it won’t compress to full travel. I am pretty sure it is not due to the lowers as I have just done a lower leg service, the problem was there before and is still there after. It isn’t a ‘bang’ harsh bottom out. It is what I would expect with an air fork, only I would expect it in the last cm or so of travel.

I have seen quite a few threads about this, but I couldn’t find one that went down a “first try this, then try that and if it still doesn’t solve it etc” line.

Is there anyone out there who can offer advice, please. I assume something has got past a seal or something is blocked.

Have you tried pressing the schrader valve inside the bottom of the air spring side inner rod (you’ll see it if you remove the air spring side lower bolt)?

Nope! Will try that now…..

There isn’t a valve in the bottom of the air shaft. I think it would be a dual air where there is a separate valve(?)

Anything else I should try?

How much travel is it supposed to have?

There’s no second chamber in a Sektor, so no addition valve or the like. Sounds like too much oil in the damper to me.

There should be a hidden valve tucked away at the bottom of the air shaft, which allows you to release any trapped air (at least there is on my Solo Air Rebas).

Too much oil in the damper is a good shout though. More likely to be that.

If not oil levels….

Does it feel notchy/crappy in compression?

My 2015 Reba’s were awful, not compressing well, sticky feeling and the culprit was a scratch in the air shaft. Replaced and it’s like a different fork.

When i was researching the issue with my forks this seemed to be a relatively common issue. It may not be yours but if you are getting other issues I it may be worth a strip down / send away for service to check.

If the fork is losing travel that’s another sign.

Thing is, it was achieving full travel when new. I have never opened the damper side. On a previous fork I took the damper out after a couple of years and the oil inside was as good as new, so have never really bothered about it.

Fork is lovely and smooth – replaced the wipers, foam rings and gave it a good clean. Reassembled with good amounts of Stendec fork grease and the right amounts of 15wt oil in the lowers.

It feels like a really nice, plush 115mm travel fork! It just won’t get to 140mm travel.

New grease.

Haven’t accidentally blocked or clogged the transfer port have you?

If you had you might find its not equalising properly and the negative spring pressure is gradually going up.

Do they extend to full stroke? I.e. is there circa 150mm of stanchion showing?

I’d take the lowers off, let air out of the spring side, remove top cap with the Schrader valve in, and and see if you’re getting full stroke on the air shaft with no air in.

Cycle the damper shaft and see if that goes full stroke.

Are you the first owner / have they always been like this?

Cheers cp.

Yes, they extend to full stroke fine.

I am the first owner – they came as part of a complete bike.

Thinking about it, when I serviced the lowers, the air side was still ‘springy’ even when supposedly empty. Because if I remember correctly, there can be a slight pain in the arse if you compress the fork before doing up the footnuts, because you can ‘lose’ the air shaft as it doesn’t push back out again when there is no air in it(?)

I definitely didn’t have this problem this time – the fork seemed to want to be a little bit springy, when they shouldn’t have been………

If the were ok before, does your rebound work much? If not you might find all the oil from your damper is now in the lower (which is also bad).

Update for anyone who might be interested.

I pretty much dismissed the ‘too much oil in the damper’ theory as I didn’t think it was the cause.

There was too much oil in the damper. I took it out following the ‘height’ recommendation on the rockshox oil chart (as opposed to the volume which gives the wrong height) and the fork has achieved full travel on this morning’s ride. The damper still works fine.

Thanks for the help STW.