Originally Posted by Polaris43
110 mm
The way to determine the BCD is to take off the chainring and measure center-to-center from one bolt arm to the next. See
Sheldon Brown ... chainwheels(sic) for details. Take that measurement and multiply by 1.7
The chainrings that were on the DT I have (VIIIH SA8) have a measurement of 76.4 and 1.7 X 76.4 = 130. You may be looking at chainrings from another model. This is a "Prowheel Forged 2N 170" the 170 is the crank length is independent of the BCD.
Just for the record, a 110mm BCD would have a measurement of 64.7mm. It is an easy error to make (all the same digits--just mixed up
). The road double 110s are often called a "compact" that was popular 15 years ago, faded, now coming back. A double won't solve the chainline issue. Read
my blog for more.
Caio