Doub-entres aside, I thought I’d follow this up.
The packer rod arrived earlier in the week and I’ve spent part of today on general bike up keep including the inserts.
First up, the packer rod foam is less dense than the Huck Norris foam. A 2m section weights 110g, so cut in half to mirror a Cushcore insert would reduce this to 55g. THats 4-5x less dense. It’s not sufficiently dense IMO to successfully mitigate against impacts if cut in half to be like cushcore.
At this point, I decided to put the entire packer rod in un-cut, which is more akin to the banger insert from Mr. Wolf.
I measured up and cut the extra length needed for my 29er wheels and attached it together with two cable ties looping through both ends.
Putting the insert in was a bit more involved than regular tubeless, but un-eventful and not excessively long. maybe an additional 5-10 minutes per tyre.
The technique of pushing the tyre bead under the insert into the rim well with a tyre lever to get enough slack absolutely must be applied otherwise you’re never going to get the tyre on the rim without breaking something.
Pushing the tyre bead down and in like this does result in the bead sitting on the top of the valve and allows air to short-circuit when trying to inflate, so be aware of that. Its a simple matter to drag the bead back over the base of the valve, but its not obvious at first.
Otherwise, inflation was uneventful, as was topping up the spooge which I did via the valve and the bead.
Its clear that the insert is compressed by the tyre pressure. I did two today, and one rattles in the tyre where is circumference has reduced and is no longer tight on the rim. After I noted this, I made the second insert a tighter fit and that one is fine.
Its obvious that I need less pressure to get them feeling the same. I’m hopeful, given my preference for low pressures that the higher volume insert will behave a bit like a rockshox air token and increase the progressiveness of the tyre compression as well as providing physical bottom out resistance. Air volume in the tyre must be reduced by at least 60% I’d have thought.
Proof will be in the pudding. First ride out tomorrow, but on the soft soggy Mendips, I’m doubtful the riding its going to test it that much.
Details are:
LB 35mm 29er carbon rims
50mm packer rod
Schwalbe Nobby Nics 2.35.