Determinig BCD and chain rings
Hi,
I'm considering changing the chainrings on my cyclocross bike from the current 48/39 setup to something a little smaller so I can (hopefully!) improve my pedaling style and make it a little smoother with the smaller gears.
However I'm not sure what I can actually fit - it's a Truvativ crank set but I'm not sure what model, there's nothing on them except 'Power Spline' and they don't appear on the Truvativ website anymore.
So, how can I work out the BCD so I know what chain rings I can fit? While we're on it, any recommendations for chain rings?
Cheers,
Steve
I'm considering changing the chainrings on my cyclocross bike from the current 48/39 setup to something a little smaller so I can (hopefully!) improve my pedaling style and make it a little smoother with the smaller gears.
However I'm not sure what I can actually fit - it's a Truvativ crank set but I'm not sure what model, there's nothing on them except 'Power Spline' and they don't appear on the Truvativ website anymore.
So, how can I work out the BCD so I know what chain rings I can fit? While we're on it, any recommendations for chain rings?
Cheers,
Steve
0
Comments
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"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools :?:SheldonBrown0 -
Take off a chanring and put it on a piece of paper. Mark a dot in the centre of each bolt hole, and draw a circle through the dots with a pair of compasses. Measure the diameter and you have your BCD.0
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It's almost certainly a 130BCD with that chainring selection though (I'll take a wild stab that it's an Elita - that's what came on my x-bike with those rings), so the smallest you'll get to fit is a 38.0
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Look at http://www.specialites-ta.com/images_tech/techRte.pdf
Bottom left corner has the BCD and the distance between two bolt centers. 130mm BCD is 76.4mmRecipe: shave legs sparingly, rub in embrocation and drizzle with freshly squeezed baby oil.0
