Use Road Position to set up the Mountain Bike, 3 Video Series
I had a subscriber on my YouTube channel pose a good topic for a video. They asked how you might take measurements that you have from a successful road bike fit and apply some of that information to help properly set up the mountain bike.This can also be thought of as "How are the road and mountain bike position similar/different?"So can we take measurements from one bike and translate that into some bike fitting parameters for the other bike?As you might imagine the answer is "we can" and "it depends". Of course we won't be able to solve every bike fit issue with a simple formula -- bodies and bikes just don't work like that. But I think we can provide some rough guidelines and make it easier to draw conclusions from one bike to another.This turned into a three-part video series because of the sheer amount of information as I was trying to cover as many variables as possible.Part 1 discusses the cleats, Part 2 is about saddle position and part 3 refers to handlebar setup.https://youtu.be/hUw3JF1aih8 https://youtu.be/rfrdiHhlqzo https://youtu.be/r5SGciReNQM
More explanation on Part 3, Bar Position
My mountain bike bar position of + 8 cm above the saddle is probably a bit atypically high for an XC style bike, because this bike was set up as a single speed and getting up some of the steep hills around here requires a lot of standing and grinding a very low cadence. So having a high bar position to leverage in this scenario is really helpful. Under normal circumstances an XC position might not be normally this high -- it might just be a couple centimeters higher than my road bike. This is assuming that you want to make it easier to tackle some steeper or slightly technical off-road terrain -- this isn't always the case: Many racers who compete on some very sanitized mountain bike courses easily get away with very road-like positions.Saddle height is typical -- just barely lower than my road saddle height. With a mountain bike meant for more technical terrain -- 6" travel bike -- could be 4-5 cm lower. But this need for a lower saddle height is becoming less necessary as dropper posts become more prevalent. When you can quickly and easily bump the saddle down 1 cm or even 10 cm as you can with a dropper, there's really no need to start lower -- you can choose to take your road saddle height and make this your highest saddle position on your mountain bike as well.Rules:
- Cleat position -- roughly same
- Saddle height -- 1cm-4cm lower, maybe closer to 4 cm the more technical your riding, unless you have a dropper post
- Bar reach and height -- mountain bar will be higher and closer to saddle
How much closer depends on:How aggressive your road position is?How technical your riding on the mountain bike?If your road position is very aggressive because you're a hardcore racer and you ride your mtn bike on very technical terrain, then they might be very different -- your mountain bar reach might be much shorter and bar height much higher than your road bike (could be 15-25 cm shorter on the reach and about 8-15 cm on the height. On the other end of the spectrum, if your road position is very relaxed, and you ride mostly moderate terrain on your mountain bike, then the bar reach and height of the mountain bike might be just barely different than your road bike (they could be the same).These are the extremes though -- what are more standard numbers?Reach -- mountain bike 5-12 cm shorterHeight -- mountain bike 3-7 cm higherJust know that these are very "squishy" ranges -- there can be many reasons not to fall inside of them or to be "in range on one of them and far out of range on another.I had a client recently who came in for fittings on all her bikes and her bar height difference between the road and the mountain ended up being only about 1 cm but the reach difference was almost 20 cm shorter on the mountain bike. This seemingly strange combination had to do with some low back issues the client chronically suffers from on the bike as well as the fact that she is very small and was able to find a true size XS mountain bike, but the road bike she had was not sized perfectly to her since a "S" was what she was riding.Another recent client had a 6 cm difference in bar height and a 17 cm shorter reach on the mountain bike.