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I have a bit of a disproportionate body. I am 176cm (5'9") tall, but my inside leg height is only 76cm (2'6"). I want to build a fixed-gear bike and I am looking for a frame of the right size for me. The plan is to use it to commute. All the track frames I could find are either low-pro, or with small backward sloping. And most of them are very compact, which means the top tube is short compared to the seat tube, which really doesn't fit my body. Of course, it is very hard to get a tailored track frame for a good price.

The only solution is then to buy a small frame and use long components (stem, seatpost). Is this a good solution or you can think of something else?

  • Consider buying a bike that fits you correctly, and then converting it to single speed with a simple cog replacement or to fixed by replacing the whole rear hub/wheel. Fit is the single most important thing. – Criggie Feb 12 '17 at 18:50
  • What about a single speed cycle cross frame? They typically will have a higher stack than a track frame. – Rider_X Feb 12 '17 at 19:01
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    @Criggie fixed gear needs horizontal dropouts and special threads. Most frames and wheels just aren't convertable. – ojs Feb 12 '17 at 20:58
  • @Rider_X I believe this question was about getting lower stack height, not higher. – ojs Feb 12 '17 at 21:00
  • @Criggie I am not after a convertible, mostly for estethic reasons. – Alessandro Cosentino Feb 12 '17 at 21:32
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Track frames in general are designed for manouverability, not stability or comfort. This does not make them very good commuter bikes, but if you absolutely need a track frame you know what you are getting into. Extra long stem tones down the twitchiness a bit, but also moves the weight distribution towards front wheel.

Another solution would be buying a road frame with horizontal dropouts and not installing a rear brake. This will get you a top tube that is only moderately short related to your body, but would lose some credibility (if it was 2007, this is 2017 and track bikes are old news anyway).

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  • Very good point on the weight distribution moving towards front wheel! – Alessandro Cosentino Feb 12 '17 at 21:34
  • I am not aware of road frame with a sloping geometry and horizontal dropouts. Unless you mean the usual urban frames (Mash, Cinelli, 8bar, ...), but I consider that track frame when it comes to geometry – Alessandro Cosentino Feb 12 '17 at 21:35
  • @AlessandroCosentino - Check out Surly Troll or Soma Buena Vista which both have horizontal dropouts and generous standover. By no means racing bikes (steel frames), but can take larger tires for commuting through fields of glass, or trekking across fields of gravel. – Craig Hicks Feb 13 '17 at 15:30
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+50

This won't necessarily help the OP, but it may help other riders in a similar situation.

Stack and reach defined

First, let's review what stack and reach are. Stack and reach are usually measured to the top of the bike's head tube. Here's an article by Road.cc, and a picture from their article.

enter image description here

Basically, reach is how long the bike is (i.e. the horizontal measurement). Stack is how tall it is. Stack and reach are usually measured to the top of the head tube (as in the graphic above). Your handlebar position further modifies how the front end of the bike feels. You can add several spacers under the stem. You can change the stem length. You can also get handlebars with less or greater reach and drop.

It sounds like the OP thinks he has short legs relative to his height. This should mean that he wants to look for bikes that have relatively low stack, and relatively long reach.

How would you use stack and reach to shop for bikes?

Bike Insights is a database of frames. They plotted the stack and reach of various frames, and they estimated the average stack/reach ratio as a function of frame size (possibly through regression). They characterize a bike's fit as aggressive (compared to others in its category) if it's longer and lower (i.e. higher reach, lower stack) than average, or upright if it's the reverse. For example, the 2014 Fuji Track Classic appears to have relatively aggressive fit. The gray diagonal line is the stack/reach trend of the average track bike. The colored dots are the stack/reach measures for each size of the Fuji frame I mentioned.

enter image description here

The 2006 Rivendell Quickbeam is very much the reverse.

enter image description here

So, the OP should probably find frames with relatively aggressive fit (if I understood the post correctly). He could find the stack and reach of his current frame, and possibly estimate his desired stack and reach. Naturally, he could ask around at local bike stores; the more experienced sales people should have a sense of which brands they carry are more aggressive or more upright in fit. If the OP uses Bike Insight, their search function appears to allow you to search for a maximum and minimum stack and reach, so the OP could search this way if he can estimate a desired stack and reach. He could also ask a bike store for recommendations, e.g. "I ride about a 52cm frame, and I'm looking for a new track frame with relatively aggressive fit." Bike stores would probably understand nominal sizing more than raw stack and reach numbers, although they will be able to look up stack and reach.

The main limitation of Bike Insight is that the frames in the database are limited to what the site owners have been able to mine from public data, or to what interested users have entered. Thus, this isn't a complete database, and it doesn't have many track frames in it. Also, stack and reach may not be provided by all manufacturers, and older frames in particular may lack these measures. They can be estimated from other measurements, but not all manufacturers may provide the necessary detail. This doesn't affect more current frames as badly.

The limitation of bike stores is that you're limited to the brands they carry, and the sales staff may not be familiar with all the brands they carry. In the US, Trek and Specialized seem to be encouraging retailers to mostly carry their own bikes. Where I live, one chain is mainly a Trek dealer, and it has only a few other brands (mainly ones affiliated with Quality Bicycle Parts, e.g. Salsa). Another chain is mainly a Specialized dealer, and it also carries a few QBP brands, but no others. This may limit shoppers' choice.

Bike Insight doesn't appear to have nominal size as a search parameter, so it isn't possible to tell the site to, for example, "find 52cm bikes with aggressive fit." Many bikes are sized categorically, e.g. S, M, L, XL, possibly with XS and/or XXL, so the number of size categories varies. Some frames are still sized in centimeters, like the two example frames I gave, but this frame size can be arbitrary as discussed below. Thus, nominal size may not be conducive to being used as a search parameter on Bike Insight. I'd still recommend knowing your approximate frame size if you shop at a store; for this purpose, I would estimate a size based on a virtual top tube measurement (i.e. the length of the top tube as if it were level; in the first picture, extend the reach measurement backwards until it intersects the center of the seatpost).

In a more general case, someone with proportionately short or long legs could use the same information. If one is shopping for road bikes, then the average performance road bike (i.e. a road bike designed mainly for racing, e.g. the Trek Emonda or Madone) should have shorter stack and longer reach than an endurance road frame of the same size (i.e. a road bike designed more for long enjoyable rides, e.g. the Trek Domane). Shoppers might want to take this into account. Naturally, bikes will vary within the category as well, e.g. within performance road bikes, Specialized frames appear to have relatively aggressive fit, whereas Trek frames appear to be about average.

Also, some riders may be sensitive to the bike's seat tube angle, which affects how far forward or aft you can position the saddle. I believe most people are not in this situation, but it is worth noting. (I prefer a very forward saddle position, and I can't achieve this on bikes with less than a 74 degree seat angle, which does rule out a few gravel bikes in my size.)

For an example of nominal frame sizing, the Specialized Roubaix is a performance road bike. It's available in 44cm, 49, 52, 54, 56, 58, and 61cm sizes. In the past, road bikes were often made 'square', i.e. a 50cm seat tube and 50cm top tube, and the I believe the nominal sizes would correspond to the ST and TT measures. In the Roubaix, each size's virtual top tube measurements are usually longer (sometimes much longer) than the frame's nominal size. They are compact frames, so the seat tube measurements are all smaller than the nominal frame size.

Compact frame design and miscellaneous thoughts

Speaking of compact frames, i.e. frames with sloped top tubes, my recollection was that this design started in mountain bikes. Giant Bicycles may have been one of the first manufacturers to offer compact road bike frames. The design has become commonplace. This SE post discusses compact frames and their pros and cons.

I recall that one of the advantages is that with a compact frame, a frame with a fixed reach may be able to fit more riders. Riders vary in their leg length, after all. If you only have access to frames with level top tubes, then a rider with short legs will be limited in their frame choice by their standover clearance. A compact frame can give them more standover clearance for the same reach.

I do not believe that compact frames have inherently shorter reach than traditional frames. The OP may be confused about compact geometry. This may stem from a language barrier and unfamiliarity with this terminology, and the OP hasn't clarified. In any case, I'd focus on the stack and reach of the frame, rather than the nominal size. If the frame's reach is correct but you have a lot of standover clearance, I don't believe this is abnormal. Most bikes come equipped with 350mm seatposts as standard, and it appears pretty common to have a lot of seatpost exposed. However, if the OP really has short legs, then he will have relatively little exposed post.

(A personal note: I am 5'5", or 165cm tall. I have relatively short legs. I have about 7cm of exposed seatpost on both my bikes. My gravel bike came stock with a 350mm seatpost, so the vast majority of the post is well inside the frame.)

In general, many professional road cyclists are known to take relatively small frames and use very long stems. Their positions are very, very much lower than the average cyclist, so they may need to do this to achieve a low enough position. In any case, this demonstrates that it is OK to buy a relatively small frame and use a long (within reason) stem and seatpost. (As a personal example, most bikes in my size come stock with a 100mm stem, but I need a 120mm stem on my gravel bike.) This by itself should not disqualify a frame. Some riders may want to consider toe overlap: if you turn the wheel at very low speed, your toe can contact the front wheel if it is too close to your foot. If you are riding a small frame, this can be worth considering. I think that taller riders don't typically experience toe overlap, however. In addition, toe overlap doesn't affect you when riding at speed - you lean the bike to turn, and you usually won't lean it far enough to contact your toe. It can be an annoyance when starting from a stop, but I believe most cyclists can learn to deal with it.

The one time I've ever crashed from toe overlap happened in the sand pit in a cyclocross race. I was not very experienced, and my front wheel was wandering back and forth a bit. Unfortunately, I happened to jerk the wheel just at the time when one of my feet was at the 9 o'clock pedal position, and I went down. This was a mild mishap, considering that it happened at very low speed and on a soft surface. I relay this to illustrate how atypical it is for toe overlap to bring someone down on a road bike.

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In the 70s and 80s a lot of (mostly cheaper) road bikes were built with the same length top tubes all throughout the size run, usually in the 57-59mm range. They worked really badly for a lot of people but they might help here, especially since they all have horizontal dropouts.

Other than that, the cheap option is probably a long stem, and the good one is a custom frame.

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IMO getting a bike with the proper fit is most important. If possible I would highly recommend a professional fitting at a local shop. A poor fit not only will be inefficient but will likely be uncomfortable and may handle poorly.

A frame with vertical dropouts can be made to work by installing a chain tensioner into the derailleur hanger. There are lots of brands out there starting for as little as $15 and going to well over $100 for the tensioner made by Rohloff.

Here's a link to a single speed forum with a discussion on chain tensioners. SingleTrackWorld: Single Speed Chain Tensioner

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  • Chain tensioner works great for singlespeed with freewheel, but not for fixed gear. – ojs Feb 19 at 7:31

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