Video: Front Brake Skills for Steeps & Rock Rolls

 I recently read an article about whether we need to relearn how to ride on bikes with modern geometry. I think with the way geometry has changed over the years it's a valid point. Like the example you gave

 @Jacquers: you really do, my Trek Slash will push the front end in corners if you “get in the back seat” but rail them if your centered/weighting the bars. I used to buzz my ass on the rear tire all the time riding old 26” bikes but now with “long low 29er” geometry you are never that far back behind the saddle.

 Nah, centered between the wheels (or actually, between the tire contact patches) has always been a good idea. It is just that the front center grew more than the rear center of the years so "centered" is now a different position with respect to the bb. Mind though that with bigger wheels (larger rims with higher tires too) and when descending, the tire contact patches both move a bit rearwards with respect to the axles (when looking relative to the earth, not relative to the bike obviously) so you'll still need to shift back more than with 26" or 24" wheels. But the increase in front center more than compensated for that.

A good practice is to learn to climb and descend on a mountain unicycle (MUni). Feedback on where you are with respect to the tire contact patch is quite immediate.

As for relearning to ride with "modern" geometry, I don't know. I feel I should have made the transition much earlier. My previous hardtail frame was a DMR Switchback with 420mm chainstays and I don't know what the front center was, but reach was 375mm and head angle must have been 69deg (with a 115mm headtube and a 130mm travel fork, unsprung). At about 6ft tall I could just about handle it, until I got myself Catalyst pedals and shifted my feet forwards (from ball over the axle to midfoot over the axle). That effectively increased rear center and reduced front center. That tipped the scale from "just doable" to "too sketchy" and I've had some bad crashes since. I got myself a new frame about two years ago. A BTR Ranger still with 26" wheels, but with 415mm chainstay, 460mm reach and head angle is 63deg (with a 150mm head tube and a 120mm travel fork). It may have taken me one week to adapt and after that I felt right at home.

I started late 2001 and even though people indeed told me to lean back on the descends, it never worked for me. I had front suspension but no rear. And after half a year I got a hydraulic disc brake in the front but stuck with the useless V-brake in the rear (because it wouldn't take disc brakes and didn't want an hydraulic rim brake there as I expected the brake booster would catch too much mud as a caked 2.3" tire would hardly clear). So the front wheel offered me much more control than the rear and I developed my style around that.

 @Honda750: Modern 9ers are less forgiving of poor cornering technique is my take. Pro level riders don't seem to have nearly as much of an issue with the shift in geo, while others like myself have to learn to corner properly.

With the Slash in particular, it has a short reach which makes getting weight on the front a little awkward. I ended up going with a 60mm stem and running the bars as low as my back would allow to try to make the body position feel more natural when cornering. Recently I switched to a '20 Enduro, it has ~30mm longer reach and now front/back weight balance feels far more natural. For some it may not be an issue, but short reach was one of the major design flaws of the Slash for me.

 Looking at it from a physics point of view, your center of mass' force vector has to pass through the front tire's contact patch to maximize traction and control. How far back your butt has to be for that condition to be fulfilled is dictated by the inclination of the surface you are rolling over and the bike's geometry. A steeper head angle will certainly mandate a more rearward position on the bike.

 @southoftheborder: Only in statics. If you need to compensate for sudden decelerations (through obstacles, rough terrain etc) you need to be even more rearwards whereas when accelerating you can/should be a bit more forwards (for instance when dropping in a quarter). Also, the headangle is only part of what leads up to the longer front center.

 www.zeptechniques.com

 Ha, you downvoters apparently didn’t see 7:30 in the video!