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minichamp31
05-11-08, 08:04 PM
That a toptube measurement isn't always accurate. At the track I rode a kid's bike that had a 21.5" toptube and it was a pro size. The only reason it was that long was because of the angle of the seattube. It didn't feel that much longer at all than mine, and mine is a 20" TT.

ChristAir
05-11-08, 09:24 PM
Handlebar angle has a lot to do with it and where the seat rails are relative to the clamp. I run 17-19 in TT and I'm 6'. It depends on your settings.

wethepeople
05-11-08, 10:51 PM
Christ is wrong, again.

ChristAir
05-11-08, 11:04 PM
A 20TT w/ 70 deg. straight seatpost will ahve almost the same feel as a 17TT w/ 60 layback seatpost. I ride oldschool, remember?

ChristAir
05-11-08, 11:13 PM
typo-have, not ahve

And with a railed seat, you can adjust the "length" of your TT. The major difference in frame lengths is the degree of your seatpost and position of your seat which are the determining factors of your BB's position to your seat. I'll try to post a pic of my 19TT (approx.) Dyno Air w/ staight seatpost and seat all the way forward. You'll find it ignorant.

fuzzbox
05-12-08, 12:01 AM
Why don't you edit your posts instead of making a new post, or proof read what you wrote. . . or don't do anything at all.

And since your probably dumb because you didn't see an edit button it is at the bottom right of your post . .close to that red reply button.

wethepeople
05-12-08, 04:57 AM
typo-have, not ahve

And with a railed seat, you can adjust the "length" of your TT. The major difference in frame lengths is the degree of your seatpost and position of your seat which are the determining factors of your BB's position to your seat. I'll try to post a pic of my 19TT (approx.) Dyno Air w/ staight seatpost and seat all the way forward. You'll find it ignorant.

No, you're wrong again. Don't forget that we don't sit, especially during races which is what Minichamp does.


Learn before you speak son.

ChristAir
05-12-08, 08:05 AM
Then why do you think that I mentioned the seatpost degree...for my health? Seat position relative to BB is VERY important when using your seat for control, especially in racing.

wds178
05-12-08, 08:30 AM
WTP is basically right.
A short TT w/ a layback will feel the as a long TT w/ a straight post in regards to your body position when sitting on the bike at a stand-still.
BUT both bikes will handle completly differently once you start to ride.
There's a LOT of things to consider when determining how a bike handles. TT length is just the tip of the iceberg.
-Bill

wds178
05-12-08, 08:30 AM
A 20TT w/ 70 deg. straight seatpost will ahve almost the same feel as a 17TT w/ 60 layback seatpost. I ride oldschool, remember?
No, one will handle like a bike 3" longer.
-Bill

ChristAir
05-12-08, 09:04 AM
I see what you're saying, but that's why I included the seatpost angle. Like I said, let my get some pics when I get back from Raliegh. I have a circa 90's and 06'.

wds178
05-12-08, 09:25 AM
It won't matter unless the bikes are identical. The bikes will still be two bikes that differ greatly in handling. Take my 20" & my 24" for example. The seat & grips are in virtually the same spot on both bikes, yet they handle VERY differently.
You can adjust your seat all you want w/ laybacks, rail position, etc & it'll have no effect on how your bike handles. Only on where you put your butt.
The ONLY way seat postiton will effect bike handling is w/ seat tube angle. Take two bikes w the same geometry except one has a 71deg ST & one has a 69 deg ST. They both have a 20" TT. Now the bike w/ a 69 deg ST may feel longer when you sit on it, but will handle like a shorter bike due to the BB being pushed forward a bit because of the ST angle.
-Bill

minichamp31
05-12-08, 05:01 PM
Yeah, what I was saying is the specs may say the toptube is 21.5" long, but it handles like a 20.5". And because the seattube is angled farther back, it makes the toptube measurement longer.

Pushrodbrick
07-18-08, 03:47 AM
That a toptube measurement isn't always accurate. At the track I rode a kid's bike that had a 21.5" toptube and it was a pro size. The only reason it was that long was because of the angle of the seattube. It didn't feel that much longer at all than mine, and mine is a 20" TT.

the TT measurement probably IS correct. Not all companies measure from the same point.
and you brought up the reason why.
the TT length is only relative to what your headtube and seattube angles are.
the more slack the seat tube angle with a certain TT length and the farther forward towards your bars the BB goes and vice versa.
so you could have a 20"TT with a 74.5 HA and a 74 SA
and someone else could have a 21TT with a 73HA and 69SA and feel shorter

bmx2478
07-18-08, 07:36 AM
Dude, stop posting in long-dead threads.