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Discussion Starter · #1 ·
I've long legs comparative to my torso. According to all the fit calculators my T.T should be 1.5 cm shorter than it is, while my seat tube is correct.
Is 1.5 cm too big to be correcting with a shorter stem? ( I can't go shorter on the seat tube because of back trouble.)
 

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worthless fit calculators...

Unfortunately, there's not a fit calculator out there that can accurately predict the proper TT length. Generally, it's because of differences in preferred saddle fore/aft position that can greatly affect the reach to the bars and the TT/stem length. The calculators also have no idea of your fitness level or how much saddle to handlebar height difference you might choose. These also affect your reach.

The goods news is that only a few brands have TTs that are significantly longer than most others. One of them is Trek, so I always tell short torso guys to steer clear of Trek, unless they look at the the WSD bikes, that tend to have a normal (not extra long) TT.

In addition to stem length changes, handlebar reach can be changed, although the number of bars with a 70-75mm reach rather than 85-90mm is pretty limited. After several years of using Salsa Poco (70mm reach) bars, I'm trying some normal 85mm reach bars (Easton EC-90). Of course this means using at least a 10mm shorter stem.

Getting a professional fitting is wise, but even the best fitter can only get you in the ballpark. A perfectly fine fitting for a racer might prove to be very uncomfortable for new rider.
 

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Discussion Starter · #4 ·
thanks

Thanks C-40. I agree fit calculators aren't perfect.I'm wondering specifically, provided that the TT is too long for me, would it have a negative effect on handling? Although I've been on bikes since the '70s I used to ride smaller frames (i.e 58cm as opposed to 61cm now)
before my operation.

David Kirk. current Stem is 12cm, TT is 59cm. I'm comfortable enough on these bikes but wondering what negative effect if any is caused by 1- 1.5 cm.
 

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different story...

If you have experience with a 59cm TT and 120 stem, then the fit calculator is totally irrelevant. When comparing a new frame, with a longer TT, you still have to consider the STA, if it's different than what you've been using. A more slack STA will shorten the reach.

Unless you're racing or doing many curves on a mountain descent, you'l probably not notice the difference in the TT length.

Another thing to look at is the front-center. A longer front-center will reduce the weight on the front a bit and increase wheelbase. A longer wheelbase bike might handle a little slower, but that also depends on the steering trail, whihc is another thing to look at.
 

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its so inexpensive to experiment with stem length

buy another damn stem and give it a try. My guess is most people would be completely unaffeacted as would be the handling by going from a 12 to a 10. But what do you have to lose by giving it a try. If it's a custom Kirk, wouldn't Dave have a valued opinion?

Good luck.
 

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same boat

I have the same problem, long legs, plus i have some pretty bad low back pain when I bike. The therapist tells me I just have tight hamstrings and need to do some exercises. I've gone custom for my last two bikes but in the future I think I'd rather just buy a stock bike because of the greater number of options with frame materials, and possible lower cost. C-40, since you always seem to be the fit guru here I was wondering if you knew what brands tend to have shorter top tubes than others. I realize, I think, that a "short" top tube is negated by a steep seat angle. Of course, my other problem is that I'm 6'2" and some brands don't even make frames big enough in the first place. Anyway, what brands have shorter top tubes than others? One that comes to mind is Time, but in order to get a large enough frame from them I'd have to spend nearly $3000, and for that much money I could just go custom.
 

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maybe LOOK....

I've been buying LOOK frames because the TTs tend to be shorter. In your size, a steep STA is not common, most are 72.5 or 73. Colnagos also tend to be short in the larger sizes (but not in the smaller sizes).

Unfortunately neither makes many cheap frames. Leftover LOOK KG481 and KG461 frames can be had pretty cheap, but finding your size might not be so easy.

A great many other brands will fall into a slighty longer TT range, but it's rare to see a brand with a TT that's much more than 1cm longer.
 

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funny...

C-40 said:
I've been buying LOOK frames because the TTs tend to be shorter. In your size, a steep STA is not common, most are 72.5 or 73. Colnagos also tend to be short in the larger sizes (but not in the smaller sizes).

Unfortunately neither makes many cheap frames. Leftover LOOK KG481 and KG461 frames can be had pretty cheap, but finding your size might not be so easy.

A great many other brands will fall into a slighty longer TT range, but it's rare to see a brand with a TT that's much more than 1cm longer.
in my previous note I was going to mention that LOOK was one of the brands that doesn't come larger than a 59cm, so I figure that any frame by them would be too small.
 

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not true..

The 381 and 481 were made in sizes up to a 61cm. The newer models only go up to a 59. Also note that these are c-c sizes, so you should add at least 1.5cm to compare with c-t sizes. You didn't mention a frame size in your post. I would compare the head tube length, with the headset and maximum spacers to determine if a frame is vertically large enough.

For example, the largest size of 565 and 585 have a 199mm head tube. With the headset (15mm) and up to 3cm of spacer, this increaases to 244mm. The 555 model is 6mm shorter.
 

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i'll throw in my 2 cents. I'm 6' 2'' and ride a 58 cm TT and have experimented alot with stem lengths from 9 cm to 12 cm. my frame is a titus drop u. i have a 35" or so inseam and run 40 mm of spacer below my bars which puts them about 4 inches below seat level. i find i like the handling better with the longer stem. i can only guess it's because it puts more weight on the front end. the longer stem gives much more desirable handling traits when out of the saddle on climbs when you're rocking side to side. i find this interesting and definately significant....you'll notice it. it's also better when decending. the down side is the longer reach is less comfortable. in my limited experience, for handling it seems to be better to have a longer stem shorter TT combo. recently i switched out my 43mm offset fork for a 40mm and liked the result.
 
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