Weird one; airlock when dropping my seatpost.
Just built up a 2nd hand Mojo frame and put in a reverb, on compressing it there’s noticeable resistance caused by the air in the frame, I can hear it escaping round the headset bearings.
The headset in it doesn’t fit snugly and I’m about to change it and I suspect any gaps will be closed or at least much reduced.
There are two bottle bosses in that unusable place under the downtube but I don’t particularly want to leave them open to the elements.
Anyone else had this issue and solved it?Posted 4 years agoAndy RSubscriber
I don’t have a Reverb, so I don’t know, but when it compresses does it bleed air to atmosphere? I would have thought it was a sealed unit but even if it’s not, I can’t see that the small amount of air displaced is going to be noticeable in the whole volume of the frame tubes.Posted 4 years agoSuperficialMember
Same happens with my Yeti ASR-5 / Reverb combination. It’s not a problem. Once I’d cycled the Reverb a few times it seems to stop (for me at least).
The Reverb isn’t completely sealed. The’re an empty area around the air spring shaft that’s open to the bottom of the post. I guess it’s 20-30ml which is displaced when the post is compressed.Posted 4 years agoNorthwindSubscriber
My KS isn’t sealed, and yep you can hear the air coming out past the headset when you drop it. It’s never been a problem, though. (the frame’s got a hole in the BB shell which you’d think would let the air out easily, but it seems like it’s enough air moved quickly for other exits to get some flow as well).Posted 4 years agotoys19Member
clubber – Member
As he said – the reverb is sealed. Are you sure it’s coming from the headset and not a sound from fork/shock compressing?
I dont think it is sealed, my reverb did this until I took the heli tabe off the drain hole of the BB on my covert. I had issues with the reverb getting graunchy with mud and crud getting in through the bottom and messing up the bushings.Posted 4 years agobigyinnMember
Are these Carbon frames?Posted 4 years ago
Im guessing they are, so they won’t have the little “blow holes” like they do in steel or ally frames near the tube ends. Meaning the frame is “sealed” once all the components are fitted.
You could either drill a holes in the BB area or a more elegant solution would be to fit a hollow bolt in place of one of the bottle boss bolts.
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