Joined: Aug 2009
Posts: 2,786
Likes: 749
From: Winslow, AR
Bikes: '83 univega gran turismo x2, '85 schwinn super le tour,'89 miyata triple cross, '91 GT tequesta, '90 yokota grizzly peak, '94 GT backwoods, '95'ish scott tampico, '98 bonty privateer, '93 mongoose crossway 625, '98 parkpre ariel, 2k'ish giant fcr3
the actual problem i've ever seen with installing 700c on some older canti/27" bikes is not so much the boss spacing, but the height from fork end/dropout up the legs or stays. they're set high up there, i think, because many older canti's had little to no vertical adjustment. otoh, when converting, older non-threaded post type canti's can make up for boss to rim spacing discrepancies (horizontal adjustment) while new threaded types make a little trickier though doable. otherwise, you have to get a type of canti..older or newer...than can allow one to move the pad height adjustment as low as possible (vertical adjustment) to meet rim squarely. i don't know of any that will allow the pad/s to adjust that low. so, i would think some of the older 27" frames just aren't good conversion candidates. hope that makes sense
Last edited by thook; 10-04-21 at 09:41 PM.