Body position (standing) is variable but there is only so far over the bar a rider can get in terms of weighting the front wheel? Shortening the stem 20mm - while lenghtening the reach a similar amount - isn't changing a rider's position relative the handlebar but it is changing the relationship of the handlebar to the wheel.
Two other factors to consider with current trends are generally narrower bars - which you wrote about- (less weight on the front wheel) and much higher stack heights (when it comes to saddle-bar relationships bikes are actually trending longer + higher) which is also moving weight off the front wheel.
Interesting that Specialized has also changed geo for the Epic around a shorter stem (60mm - short for XC) and reduced offset but the Enduro this year gets a longer TT and shorter stem (45mm vs. 60mm) with the same offset. I'd bet $20 Specialized Enduro 2019 has a reduced offset Ohlins fork.
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One last comment (apologies for the long reply) but I think the throw-back XC geo argument makes for nice marketing but is perhaps being overplayed?
Not that mountain bikes haven't evolved from long stem/narrow bar/steep HTA 26" gravel grinders but having ridden 29'ers a long time 51mm offset wasn't adapted en masse until Fox released their 34 for the 2012 model year - RockShox followed suit with the release of the 29'er Pike - specifically to deal with 29'ers evolving to become slacker more aggressive machines.
Aug. 24, 2017, 1:13 p.m. - Andrew Major
Body position (standing) is variable but there is only so far over the bar a rider can get in terms of weighting the front wheel? Shortening the stem 20mm - while lenghtening the reach a similar amount - isn't changing a rider's position relative the handlebar but it is changing the relationship of the handlebar to the wheel. Two other factors to consider with current trends are generally narrower bars - which you wrote about- (less weight on the front wheel) and much higher stack heights (when it comes to saddle-bar relationships bikes are actually trending longer + higher) which is also moving weight off the front wheel. Interesting that Specialized has also changed geo for the Epic around a shorter stem (60mm - short for XC) and reduced offset but the Enduro this year gets a longer TT and shorter stem (45mm vs. 60mm) with the same offset. I'd bet $20 Specialized Enduro 2019 has a reduced offset Ohlins fork. ... One last comment (apologies for the long reply) but I think the throw-back XC geo argument makes for nice marketing but is perhaps being overplayed? Not that mountain bikes haven't evolved from long stem/narrow bar/steep HTA 26" gravel grinders but having ridden 29'ers a long time 51mm offset wasn't adapted en masse until Fox released their 34 for the 2012 model year - RockShox followed suit with the release of the 29'er Pike - specifically to deal with 29'ers evolving to become slacker more aggressive machines.