I lay a metre rule’s front edge across the dead centre of both grips and then measure the distance from that edge to the centre of the top cap bolt with a tape measure. It’s a bit of a fiddle but I got curious after noticing that riding mates running ~35mm stems tended to have their bar rise more vertical or forwards whilst mine is more in line with my head angle - so although I run a 50mm stem on both bikes the effective stem length was about the same as with these shorter stems.
I tried a 35mm stem and found it too nervy as the effective stem length was about zero. I’m on 40mm rise 770mm wide Renthals (well they’re 760 but the grips add 10mm), which have a bit less backsweep than the norm (7 deg IIRC).
May 13, 2020, 11:05 a.m. - a.funks
I lay a metre rule’s front edge across the dead centre of both grips and then measure the distance from that edge to the centre of the top cap bolt with a tape measure. It’s a bit of a fiddle but I got curious after noticing that riding mates running ~35mm stems tended to have their bar rise more vertical or forwards whilst mine is more in line with my head angle - so although I run a 50mm stem on both bikes the effective stem length was about the same as with these shorter stems. I tried a 35mm stem and found it too nervy as the effective stem length was about zero. I’m on 40mm rise 770mm wide Renthals (well they’re 760 but the grips add 10mm), which have a bit less backsweep than the norm (7 deg IIRC).