deilenberger
A bozo on the bus
Hammam,
I'd generally agree for the stock BMW TPMs - it's basically a warning system. The BMW readout is temperature compensated.. meaning what you read with your pencil gauge and what reads out on the display will only match at 20C or wherever BMW set their base line. On your pencil gauge - if the tire is warmer then 20C you'll see a higher pressure, colder - lower pressure with your pencil gauge.
One thing I've noticed - since getting a good TPMS on my bike (aftermarket that gives me actual pressures and actual tire temperatures) - I never lose any air. The topping off that used to be necessary almost every time I checked tires before is gone. I can only theorize that the loss of air was involved with the manual checking of the pressure. It takes very little loss of air on a bike tire to drop the pressure 1-2 PSI. Plus since the readout isn't temperature compensated, you're always chasing pressures.
I find a TPMS valuable enough that I went to some trouble and expense to add it to my bike. YMMV - and to each his own, but I'd expect to see this mandated by some safety organization (perhaps in Europe first..) before too much time goes by.
I'd generally agree for the stock BMW TPMs - it's basically a warning system. The BMW readout is temperature compensated.. meaning what you read with your pencil gauge and what reads out on the display will only match at 20C or wherever BMW set their base line. On your pencil gauge - if the tire is warmer then 20C you'll see a higher pressure, colder - lower pressure with your pencil gauge.
One thing I've noticed - since getting a good TPMS on my bike (aftermarket that gives me actual pressures and actual tire temperatures) - I never lose any air. The topping off that used to be necessary almost every time I checked tires before is gone. I can only theorize that the loss of air was involved with the manual checking of the pressure. It takes very little loss of air on a bike tire to drop the pressure 1-2 PSI. Plus since the readout isn't temperature compensated, you're always chasing pressures.
I find a TPMS valuable enough that I went to some trouble and expense to add it to my bike. YMMV - and to each his own, but I'd expect to see this mandated by some safety organization (perhaps in Europe first..) before too much time goes by.