Frame geometry question
#1
o harro buttercup
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Frame geometry question
I want to get a more aggressive frame geometry for my FG bike. I currently have a 72/73 w/101 wheelbase. I'm down to two frames, one w/a 74/75.3 w/95.5 wheelbase or a 72/73 w/95.7 wheelbase.
My question is: what plays into the handling more...head/seat tube angles or wheelbase? I understand a shorter wheelbase will be more agile but will I notice a lot of difference if I go w/the steeper tube angles?
I just use this bike to commute to the part time job and ride around town. No racing or anything like that.
My apologies if it's a newbie kind of question.
My question is: what plays into the handling more...head/seat tube angles or wheelbase? I understand a shorter wheelbase will be more agile but will I notice a lot of difference if I go w/the steeper tube angles?
I just use this bike to commute to the part time job and ride around town. No racing or anything like that.
My apologies if it's a newbie kind of question.
#2
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The answer to your question depends on more factors than you've laid out here. Wheelbase is important but so is trail, which is influenced by head tube angle but also fork rake. Seat tube angle doesnt mean much for steering geometry (someone will correct me if Im wrong) but it has a big effect on your riding position and weight distribution which in turn affects steering as well as how the bike feels climbing and descending when your CoG moves around. I recommend that you google Dave Moulton and check out his blog entries on bicycle steering geometry. They are a nice simple introduction to a complex subject. At any rate though either one of those frames will probably handle more snappy than your current bike, and odds are that the steeper one will be more so.
Last edited by mander; 05-30-07 at 03:28 PM.
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+1 for doing some reading. Moulton and Sheldon Brown are two good places to start.
But if you know you want more aggressive handling, [and all other things being equal], the bike with shorter wheelbase AND steeper angles will feel tighter. I disclaim that because rake/trail, clearances, frame material & construction, and other things will certainly affect the perceived feel of the bike once it's built up. Not to mention your component or group selection.
But if you know you want more aggressive handling, [and all other things being equal], the bike with shorter wheelbase AND steeper angles will feel tighter. I disclaim that because rake/trail, clearances, frame material & construction, and other things will certainly affect the perceived feel of the bike once it's built up. Not to mention your component or group selection.