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Bottom Bracket Height


I just finished my new bike build that was from modding an old mountain bike. The bottom bracket ended up being higher that I really wanted. I was always a big fan of a really low bottom bracket. I was going to fix it and I started noticing some things. I know the contact (wear) spot on my mallet head is different, so something is changing (since I didn't change shaft length).

It seems that I can better manipulate the ball in front of the front tire. It may be my imagination, but it feels like I have more power being higher..

Is there anything to these that a higher bottom bracket contributes to or is it something else with my frame I am missing.

Is there anything to this?

Well basic Science states that the straighter your arm/mallet the more power you can achieve, so if by being lower you had to bend your elbow when hitting, it could reduce your hitting speed, whereas being higher up and allowing you to hit with a straight arm will produce more power.
As far as the ball in front of your front wheel it would change the angle you create with your arm when reaching over the wheel, by making the angle less (by being higher up) it would put less strain on your arm, and require less moving and turning of your body. Now granted the effects you feel are probably much greater than the actual advantage you are gaining. In order to see a major difference as far as the math and science goes you would need to remove around 15 degrees from that angle, I'm doubting you grew to 8 feet tall or sitting over a foot higher, so that just wont happen.

so that's whats to it...but it is all personal preference when you start getting this in depth

Any personal experience out there of someone who moved from a high bottom bracket (I am thinking the Joust, right?) to a lower one? (Marino?) or the other way?

just saying..
you can lower your BB by just using skinnier tires...

that being said, in the last year I went from 2.0" (50-559) to 1,5" (42-559) to 1,125" (28-559) tires on the Joust and love It. better acceleration, feels more stable @ high speeds w/o sacrificing maneuverability. Downside is, that I have now sometimes pedal strike on the ground, even though i use clipless pedals, 165mm cranks..

But regarding your question.
I don't feel any difference in terms of Mallet/ball control. I am using a very short mallet though. But from what you are writing, to me it also sounds as if it "changed the mallet length". like sometimes changing 10cm makes hardly a difference whereas on more cm makes all the difference.

but you changed the whole bike not just the "bb-height"

Also: comparing to your old bike:
did you keep the total length of the seattube (including seatpost) constant?
did you "change" the seatangle (regarding the middle of the saddle, I see its put waay up front)

--> both will mean, that you changed the way you are sitting on the bike and what angles your back will have in different situations, which has a lot of influence on the "rest of your body"

(PS: awesome work on the bike and excellent saddle choice ;) )

Thanks Richard (again).

I just wanted to make sure. I have been running a low bottom bracket, mallet length, and 2.0 tires for years now.. The new set up has 1.5's and a high bottom bracket. I just wanted to double check that there wasn't something else at work about higher bottom bracket that I haven't heard about. I always run 155 or 160 cranks so striking has never been an issue.

I am sure it is something in the ways everything is setup as LOTS of things changed. The seatpost tube is the same length but the angle is way slack. I had to scoot the seat up on the rails to keep from wheelie-ing. The seat to stem etc, should be the same too.

I may drop the BB height a tad by shrinking the back triangle a tad more. Increasing the size of the 3rd triangle on the top tube and dimpling the seat tube.

Oh and I just switched back to this saddle (which I like) because my Brooks Swift ripped in half!