Does BB height matter to you?

BB height is always an interesting discussion. scott is so correct about some of this being preferential. I absolutely hate serious pedal smack, and some bikes have it in spades...others don't. There are so many factors. On the handling issue with some tall bikes and many riders, there is often a problem with a decently tall BB. I had an '03 Bullit with a very tall BB...forget the number at this point...but I had installed a longer shock and fork. Though it didn't quite carve like my Nomad, I had no problem with fast cornering. I've ridden some other tall BB bikes and didn't have much cornering issue with them either.

I got to thinking that perhaps it was because I was used to riding very tall long travel dirt motors. While not a 100% comparison, you have to be very conscious of where the CG of the dirt motor is when you lean it into a corner aggressively. The height of the bike is less of an issue when you have the CG planted directly over the tires and into the bike's footprint...if you get my drift. I basically do the same thing with my mountainbikes, right or wrong. I think lots of people are more into steering and remaining as upright as possible. Of course you have to lean to some degree regardless of skill or fear factor, but leaning into the corner right at the point of the bike's CG and tire contact point being in line diminishes the impact of the BB height. It's a little bit of balancing act, and it can bite you once in awhile, but you can get used to it.

Funny thing...that Bullit didn't pedal all that efficiently, but you could pedal that sucker through some pretty nasty rock gardens without pedal smack. On the last trip to Moab with a riding buddy, his frame broke on his Spec Enduro the second day out on a 10-day trip. I bring the Bullit as a backup bike, and even with a 170mm single crown fork and the OEM sized 8.5 X 2.5 shock, the Bullit is known for a tall BB. My buddy rode that bike the rest of the trip, noticed the serious lack of pedal smack in many of the technical, rocky trails there, and absolutely loved it. As already stated...people are different.

titaniumgearsolid said:

It seems that BB height trends dictate that a lower bottom bracket is ideal. But my 5.5"-travel trailbike's 13.2 inches BB height seems to be too low for me because I keep on hitting my pedals. But I'm building another bike (old 6"-travel frame) which has 14.5 inches of BB height. I'm anticipating that there is quite a huge difference. Will it be drastic? How would it feel? Or is it just a matter of getting used to?

Whadya say? What could be an ideal BB height for the current AM bikes that are supposed to be the best balance of various compromises?

Click to expand...

Don't take anyones word regarding BB height too seriously unless you know they are riding similar trails. The lower ones will feel better when carving along, but if your trails are very rocky you'll just end up banging your pedals all the time and losing your flow.

My trails are very rocky, and low bikes just don't work very well here. Luckily I have adjustable drop outs (which I generally have to keep on their highest setting for most trails around here). However I've been riding some places where the trails are smooth enough that banging pedals would never be an issue, there the lower BB would work great.

You can learn to smack pedals less, but it's not just about skill.

Also, when you look at the listed BB heights remember that it's an unsagged value. My previous bike had a higher BB on paper, but the increased travel and the way the suspension is set up results in the new one having a lower BB when sagged and with compressed suspension. I don't think the different drop out settings on my bike make more then a 3-5mm differnce in BB height, but it feels like a huge difference on the trail.