Posted by: AndrewMajor
Posted by: Blofeld
Posted by: fartymarty
For me the spacers v bar rise doesnt matter as I run a 0mm effective stem length (grip centre through steerer centre). Therefore raising either effects the reach.
This is bang on. The only net difference should be bar sweep/rise angle once you hit your favoured position.
I remember PB talking about how they were setting up bikes for a multi-rider Field Test with different bars rather than stem spacers to “preserve the reach” and thinking it sounded like a complete waste of time. Effectively, the high rise bars in “reach compensation mode” is the same as adding stem length. Since the optics of using a stem longer than 50mm is too much for some people, you end up with these rationalizations.
I can't back this up with science but after some somewhat heated comments in a NSMB piece I wrote previously, I did an experiment with shorter stems run slammed with higher-rise bars and then longer stems with more spacers under them and low-rise bars. I was playing extremes (76mm rise bar vs. 15mm rise bar) and I couldn't get an exact matched position so there's nothing scientific about this; however, with a longer stem even if the effective position is (almost) the same the steering feels different to me (in a bad way). That's going back and forth multiple times - all in my head?
Mountain bike fit is a game of small adjustments - look at the difference 1-2 centimeters of chainstay or Reach length make - and even with the same effective stem length the steering felt different to me. I'm prepared to accept there's no physics behind that but I'll also be sticking to the shorter stem/taller bar setup.
Actually, preparing to delve into experimenting slightly shorter rise bar with a shorter stem run lower on my Walt V2 as part of playing with negative effective stem length and Reach/Stack. All for fun but on a static (rigid) bicycle it's interesting how handling changes with small adjustments.
Re-reading my post, I think I came across heavier-handed than I usually intend…Sorry about that! I have several points of frustration around this topic, mainly to do with media ignoring all aspects of bike fit other than reach.
No, I don’t think the steering effect you perceived in your experiment is all in your head. You may have been adjusting handlebar rise and sweep as well as stem-bar-steerer-system stiffness substantially in that set of substitutions. I don’t think these are negligible traits by any means. Personally, I like the steering feel of a (gaaaaak) 35mm bar, and definitely can’t chalk that up to anything other than stiffness. I am also thankful that you haven’t explicitly credited the change in reach as the main driver of improved steering in your experiment. 😂
I made some fresh tracks today and was inspired by this thread to delete an under-stem spacer. My goal was to slow down the steering a bit to compensate for minimal traction. mikesee’s steering damper for fat bikes blog post has an interesting take on this issue.