How essential is rim tape under the rim strip ? Options

[MilitantGraham]

I just fitted a pair of maxxis Minion 2.35" tyres to DT Swiss 4.1 rims using rim strips made from Schwalbe 20" tubes.
I gave up at the first attempt as it was too tight, there was no way they were going to go on.
I removed the cloth rim tape and tried again with proper tyre soap and got them both on with a bit of a struggle.
I'm wondering now if I should have used a layer of PVC tape as a rim tape under the rim strip.
Are the tubes going to bulge through the spoke holes and end up chaffing or bursting ?
Does anyone else run with no protection between the rim strip and rim and get away with it ? I'll probably be running them at 40psi if that makes a difference.

[Tony F]

I don't think I'd fancy having nothing under the 20" tube, but then I'm not known for being a risk taker.

When I fitted a UST Panaracer XC Pro to a DT Swiss 4.2 rim I had to get rid of the plasticky-type rim strip and replace it with PVC tape to stand any chance, and it still needed levering on. Last week I fitted a UST Maxxis High Roller 2.35 to a similar rim (new front tyre needed), and whilst it didn't exactly pop on, it was still possible to fit it by hand even with the plastic rim strip under the tube. It sealed instantly BTW, but then it is a UST tyre...

Just a comment here - I ran it at 40psi at Penmachno on Friday, but think I'm going to drop this a bit next time. Are UST tyres generally "harder" than other tyres?

tony

[Doug]

Yes, a bit.

[_tom_]

I just use a bit of duct tape if the rims dont allready have one of those rubber strips.

[Gareth]

The negligible weight and easy application of a double wrap of electrical (insulating tape) make it a no brainer for me. You will kick yourself pretty hard if your system fails due to this on a big ride. Just think of the rim strip bulging (and it will bulge) through all those sharp edged spoke holes...

[MilitantGraham]

Yeah, I've been thinking of that since I fitted them.
I've also been thinking of the work involved in removing the tyres, saving the sealant for re-use and refitting everything.
However, as no one has said "Yes, I've done it and it works fine", I don't want to be the first to prove it doesn't.
Oh well, looks like I'll be spending a couple of hours making a mess with the tyre soap and sealant again.

[bobosola]

I've also been thinking of the work involved in removing the tyres, saving the sealant for re-use and refitting everything.
However, as no one has said "Yes, I've done it and it works fine", I don't want to be the first to prove it doesn't.

I've re-fitted a tyre and re-used used the ghetto tube. Haven't tried re-using the sealant, but I can't see why you couldn't? The tyres do get dried sealant streaks on them in no time which I rubbed off (slow job). The ghetto tube can easily be cleaned the same way. However, if you trimmed it really close to the rim then you'll find it a pig if not actually impossible to get back on again as it tends to collapse inwards into the rim cavity. You'll need 4-5 mm spare to get a decent overlap. Even then it's fiddly as the act of getting the tyre on pushes the tube back into the rim again and it tends to move around a bit as you inflate it. Definitely do-able though. However, with Tesco 20" tubes under £3 each, you might opt for cheap replacement and avoid the fiddle factor.