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Are two centimeters alot?(13 posts)

Are two centimeters alot?jimmygroove590
Aug 28, 2003 3:17 PM
I am thinking of buying an old Bianchi frame for cheap, great condition. But it is about 2 centimeters shorter than what I normally ride. I am 5'8" and I take about a 52cm, so the bike is a 50. Is this acceptable?
It would be a little over 3/4" smaller. I think a 50 would be toHigh Gear
Aug 28, 2003 4:01 PM
small. Hell, I think a 52 would be too small for a 5'8" person. What is your inseam?
Inseamjimmygroove590
Aug 28, 2003 4:26 PM
My inseam is about a 30" to a 32" depending on if the pant leg is supposed to go all the way to the floor or just to my foot. Usually I go with a 32"
Bike inseam is measured...TFerguson
Aug 28, 2003 4:56 PM
from tight up to your crotch all the way to the floor - bare foot.

If it's 32" (81cm) then the common size calculation (81 x 0.67) would give a bike size (c-t) of a little over 54cm. If the bike was measured center to center (c-c), the calculated size would be about 52 1/2 or right where you said.

TF
I measured my inseamjimmygroove590
Aug 28, 2003 5:30 PM
It came out to be about 31 inches, so that puts me a about 53cm. But still, I wonder if a 50 centimeter frame is too small.
Assuming your measurement is accurate...Fez
Aug 28, 2003 7:04 PM
It is possible, but read on...

You would have an additional 3 cm of seatpost sticking out. That would be somewhere in the area of 20cm saddle to top tube instead of 17cm. Visually, that's a lot of seatpost, but you should have no problem setting the saddle that high with most 250mm long posts.

Fitting the top tube is also possible. You might need a tad longer stem than what you are used to, but you can figure it out if you know the relevant measurements of that frame.

The hardest part will be getting the bars high enough. The head tube is bound to be shorter on the 50 than any 53 you may be used to riding. If it is threadless, be prepared to use a combo of spacers and riser stems to achieve this.

It depends on the model, but it is possible the headtube would be 2cm or more shorter than what you are used to.
I don't think you'll have a problemDave Hickey
Aug 29, 2003 4:24 AM
I'm just about your size. My height and inseam are about 1/4 inch shorter. As long as the 50cm is measured ctc, you'll be ok...
small framestarwheel
Aug 29, 2003 6:36 AM
The main problem with a frame that's too small is you'll end up with a large drop from the saddle to the handlebar. Are you comfortable riding a bike with a large drop? Personally, I would rather ride a frame that is a little too large than too small, but I ride with my handlebars fairly high. A frame that is 2 cm too short would be a disaster for me, fitwise.
and...jtolleson
Aug 29, 2003 7:00 AM
I'm guessing that the top tube will be too short, also. If your cycling inseam is really 31 (which is a little shorter than mine and I'm not quite 5'7") then that means you are long in the torso. That 50cm is going to be small ALL OVER. My backup/retro bike is a 52 cm Bianchi and it is a little short for me (in all directions)
and if the top tube is short and you use a longer stem...dzrider
Aug 29, 2003 7:20 AM
your body weight will be further forward. I don't care for that feeling - especially with a bigger drop to the bars.
Bianchis models must have very different geometriesDave Hickey
Aug 29, 2003 6:12 PM
I have a Bianchi Premio that measures 51cm ctc and the top tube is a full 54cm. 54cm is the limit for me in TT length. Any longer and I get real uncomfortable. I was guessing the 50cm Premio had a 53cm TT. Depending on the posters flexibility, 53cm TT could work fine. The original poster didn't say what model. Assuming it's an older model, the stem height issue can be made up with a quill stem.
re: Are two centimeters alot?03Vortex
Aug 29, 2003 6:31 AM
I think its too small. I have a 32in inseam (measured bare feet from crotch to floor) and ride a 55 measured center to top of top tube. I am fitted properly and am 5'9" and use 110 stem.
Although I'm ordinarily pretty hesitant to chime indjg
Aug 29, 2003 11:15 AM
with internet fit advice, I'm willing to say that a 50 seems pretty small for someone your size. I'm your height (a whopping quarter inch or so taller) and I have somewhat short legs for my height (and a somewhat long torso). Given that my relatively short legs are still a good 5 cm longer than what you claim yours to be (hard to measure one's self and you may be off a little), I'd guess that you have a real long torso for your height. If that's right, a 50 cm top tube is liable to be really short, even with a shortish stem (fiddling just a little on "effective" top tube won't really change this much). Add to this the drop to the bars issue and you've got a real small bike.