Originally Posted by
firebird854
Hi,
I recently purchased and went through the horrible struggle of putting the Cycleops trainer tire on my rear tire. I'm using the Cycleops Magus trainer and keep getting a bulge in the sidewall during use. In order to fix this I need to deflate the tire, massage the bulged area back into place, then re-inflate (typically to only 60-80psi). I then get a bulge in another portion of the sidewall.
Anyone have any thoughts as to why this is happening? It has never occurred with a non-trainer tire, the tube being used is, well, used, could that be causing a problem?
Your tire pressure is way too low for a 23mm tire. Your tire is walking around the rim under the pressure of the roller as FBinNY explains. Inflate to the normal riding pressure or higher.
The force your roller places on the tire is controlled totally by the tire pressure. This means, if your tire is slipping excessively, inflate the tire to a
higher pressure so you can get more roller force on the tire.
EDIT: thinking about it more, my previous explanation wasn't quite right. By inflating your tire more, the same amount of deflection from the roller gives you more friction. By using a low tire pressure, you are forced to screw the roller down proportionately more. Thus, to increase the friction to the roller, you want to increase the tire pressure. Lowering it decreases your friction to the roller and forces you to screw the roller down further.
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