size of ur bike

[Love Your Dirt]

What size should ur bike be when racin small or big my GT pro series is pretty big but it does the trick

[mantra51]

Look for length. Geometry on race frames tend to be long and low. How tall are you? Top tube length corresponds to your height, and the longer your chainstays are (lower back tube, connecting Botton Bracket and rear dropouts), the lower its going to jump and manual. Street/trails bikes are shorter so they pop up off of lips more. Different companies use slightly different geometry, look around, these are the most important aspects of your bike. I also included crank sizing.
6' and up - 21' TT + (xl-xxl) 185 mm crank
5'10" to 6' - 20.5 to 21" (pro-xl) 180-182 mm
5'6" to 5'10" - 20 to 20.5" (pro) 175 mm
5'2" to 5'6" - 19.5 to 20" (expert-pro)170-175 mm

If your shorter than 5'2" maybe you should get a junior. 1 3/8" wheels etc.

[Love Your Dirt]

Ya im 5"7 an have a 20 right now i think...but i have a good idea now on the right size thanks..

[pcxl]

wow those dem's suck. im 5,9 and run a 21.3tt with 14.5 rear tri. racing you want a tad bit longer top tobe then trails street.

[mantra51]

wow those dem's suck. im 5,9 and run a 21.3tt with 14.5 rear tri. racing you want a tad bit longer top tobe then trails street.
I dont know if its possible for a number to "suck". Preference reigns supreme, if you like it, ride it. your bike is too big for you though. Stem lengths can change how long it feels in front though, Is your stem prapotionate to this 21.3 top tube you use? My cheeta is 21 TT with 16 in chainstay, and im 6''. It was sized for my by a cheeta rep. Besides i got those specs (not "dems", whatever those are) from a racing size chart, dumass. You act as if i made those up

[pcxl]

"dems" short for dementions. ahh i know my "specs" veary well, ive made a few frames my self. as far as the stem goes, your right, i run a 40 or 42mm stem (dont remember right off hand) and as far as it being to long...yea right, i still hit my knees on the bars.

and about your frame, why the 16 inch rear triangle? that would be a bitch to manual.


EDIT: miss-spelled.

[fastgreg]

i'm 6'1" about 185. my bikes tt is 20"
my bikes rear chainstay is 14.8"
and my bikes a little too short for me
thinking about the redline flight xxl
it has a 21.5" tt, and a 15.3" rear chain stay.
my cranks are 180mm and feel fine. :P

[mantra51]

wow those dem's suck. im 5,9 and run a 21.3tt with 14.5 rear tri. racing you want a tad bit longer top tobe then trails street.....

......"dems" short for dementions. ahh i know my "specs" veary well, ive made a few frames my self. as far as the stem goes, your right, i run a 40 or 42mm stem (dont remember right off hand) and as far as it being to long...yea right, i still hit my knees on the bars.

and about your frame, why the 16 inch rear triangle? that would be a bitch to manual.


EDIT: miss-spelled.

First of all, thats not even close to how you spell dimensions or mis-spelled or very. Thats why i said, "dems, whatever those are" i knew what you meant, i was just calling you out.

Second, if youve built frames and "know specs veary well" you would know that race bikes are generally always longer in the back because it keeps the bike, and the center of gravity lower on a manual, and in the air.. Only a noob would see that as harder. Manuals are about center of gravity, balance point. Its not about how easy it is to yank on the handlebars, which is what im guessing you mean by " a bitch to manual".
Look at Staats, Avent, Dingo, any racing company, their back ends are long.

Third, about your bike. Instead of running a long top tube, and a rediculously short stem, the optimal set up is a proportinate one with the same outcome.

Fourth, if your hitting your knees on your bars you need to, one: get better , and two: Get a frame and stem that fit you, you claim you have this great setup, yet you complain of a textbook symptom of a too-short stem.

And you build bikes? Yeesh.

[Billspeer]

i'm 5'9" and i know that my 21"TT s&m is about a half in. too long for me, but i mainly built it for my step-son to grow into soon, 'cause he's 14 and 5'11"...hehe
i actually race my older s&m with 20" TT and 175mm cranks, instead of 180mm like my newer one.
BUT..i've tried a lot of frames, and i know that a 20.5"TT if perfect for me(maybe 20.75 if the stem is less than 50mm), along with 177mm cranks.
i just gotta stop building my bikes for my kids to ride...lol
for every couple inches they grow, it's like another 1/4" on the TT of the frame and another 2.5mm in the crankset for every couple inches on the inseam...something like that...
that's my experience.