sillygirl

Hi quick bike-fit question:

How snug is too snug for a top tube? I should start by saying I am venturing over from the track section because bike-fit questions are better answered by roadies. I am a small women, and very few track bikes are made for our size without dropping to 650c wheels - so I am can't get the "perfect-fit"

So I considering purchasing a new frame with the perfect c-c geometry (46). However since it is track geometry it stands taller than the road bike I ride now (coverted to a fix). So the standover height is 29.5", which is .5" taller than my current ride. I have tested it out, and the fit is snug. Snug enough where it is definitly brushing against me, but not too snug where there is any actual pressure. I do have girls anatomy so I am less concerned about things getting in the way, but I am still concerned that i could cause some damage if i were to stop on an uneven section of the road.

Anyone have any thoughts or suggestions?

markhr

avoid like the plague - I was once convinced I should ride a 58cm with minimal clearance - whattamisdaketamake. Try dropping a size or looking at a different model in the same size. If the clearance is too small it's a good indication, at least for me, that bike's too big and top tube too long.

Jose R

I just got a custom track frame made for me. Its the same c-c size as my road frame (49cm). The standover height is tighter than my road frame, and it does touch my crotch. I think there are different theories on how much clearance you need for your given inseam, some recommend 1-3 inches. (Also, for me "crotch" is defined as the pubic bone.) I personally don't view it as an absolute that there needs to be much clearance, if any. As long as there is no uncomfortable pressure on your pubic bone.

Track bikes and cyco-cross bikes are similar in that they have high bottom brackets. And in both cases, at no point will you, during the normal course of riding, find yourself flat-footed across the top tube. It is the circumstances when you are dismounting or mounting that are at issue. And at these times, you will most likely have one foot on the a pedal, therefore your crotch will be far from the top tube. And as you dismount, you will still give yourself room to clear the top tube.

The only serious concern will be the potential, but unlikely, event where you crash or lose control of the handlebars and you fall forward and land crotch first on the top tube. But, has this ever happen to you or anyone you know? It hasn't happen to me or anyone I know. In a crash, we are more prone to go down at an angle, left or right. I have seem riders (pros) go down face first, but in these cases it was due to catastrophic failures of carbon handlebars. Something I don't think you will face.

MichaelW

Fuji do a Track SE in 43cm using 650c wheels. At your size what is wrong with the smaller wheel size?
Surly 1x1 comes in small sizes.

sillygirl

Avoiding 650s because i will always have more than one bike, and I want to be able to swap out the wheelsets. Plus I get "handme-downs" wheelsets from my boyfriend who feels the need to upgrade reagularly - and I dont want to lose that free source!!

sillygirl

Thanks for all of your thoughts!! I only have an 1/2 inch iof clearance now, and have never found it to be a problem - however since i do ride my fixie mainly off the track i am worried about the reagular dismounting with an even smaller clearance.

i just wish i could try it out before ordering - but cant find any shop with the small frame built up. I will one day go custom - just as soon as i am done with grad school.....

Jose R

Some times you just have to gut it and see. My two bikes are custom. I didn't do pro-fits or anything. Just picked my size and preferred geometry and ordered. In an ideal world we would have an opportunity to try out all the available bikes in our sizes.

I think since you already deal with only a .5 inch of clearance now, the extra .5 inch of TT height won't truly matter. Just don't do anything wacky during a dismount like a quicksilver off-the-back dismount.

I think in time you will learn to adapt.

Best of luck.

Adgooroo

Just wondering if you have looked at compact frames from Lemond, etc. Their geometry keeps the top tube lower than traditional diamonds for an equivalent "frame size."

telenick

Converted to fix ...cool.

Stop and go riding (like in traffic) is the only time you really need to straddle the TT. I would say make a few stop and go dismounts/mounts and see if it works for you.

SDS

I have no idea what your intended use for the bike is, but for track racing, I wonder if 650's would be stronger, accelerate better, and have less drag? I would be inclined to use them if there would not be gearing issues for the intended use.

alanbikehouston

I have discovered that with some bikes, you can get a "perfect fit" for riding, or you can get a "perfect fit" for standing with your feet on the ground...but not both.

One of my favorite bikes (which gives me perfect position when I riding) would press rather firmly against my crotch if I were to stand "flat-footed" with the bike positioned straight up in the air. But, I don't need to do that. At red lights, I lean the bike to the left and put my left foot on the ground. My right foot remains on the pedal. So easy, an elderly guy could do it (don't ask how I know what is easy for "elderly guys").

The "fad" of the last five years, started by Giant, is to sell folks road bikes that are waay too small, and then hike up the seat post six or eight inches. Great for standing flat-footed over the bike, not so hot for getting the hands positioned correctly relative to the saddle.

Prosody

You know, with the topic, How Snug is too Snug, I went dyslexic on the question, "How snug is too snug for a top tube?" I was mildly disappointed when I figured it out.