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LastPlace 09-17-06 07:49 PM

Top Tube............
With all other things being equal, would a shorter top tube give me a more upright riding position?

I started riding on a 54cm frame and have moved the components to a 56cm frame and feel comfortable and have plenty of room under the shorts. More recently I rented a 56cm Trek Pilot and had even more room but thought the shorter top tube on a 54cm might put me more upright.

I ask because I am considering buying yet another frame, a Trek Pilot, for Christmas.

Any thoughts?

Monoborracho 09-17-06 07:57 PM

Ceteris paribus....yes.

LastPlace 09-17-06 10:20 PM

Top Tube.......
This appears to be a forum with well read posters. Thanks.

velonomad 09-17-06 10:46 PM

Since the 56 cm frame seems to fit better, why not just put on a shorter stem to compensate for the longer top tube? You can also raise the handle bars to get more upright.

CrossChain 09-17-06 11:12 PM

Remember, with an (especially slacker) angled head tube, as you go higher with your stem, your bars come in closer, too. Super short, or super extended stem extensions can sometimes affect a bike's handling. Better to let a shorter top tube do some of the shortening work. Also remember that the more upright you go, the more weight goes to your butt while at the same time your beefy butt muscles are less engaged in propelling the bike.

CrossChain 09-17-06 11:15 PM


Originally Posted by LastPlace

I ask because I am considering buying yet another frame, a Trek Pilot, for Christmas.

Any thoughts?

I'm interested in hearing more about your just buying the Pilot frame. Going to the Trek site, I notice that 07 5.2 framesets are going for about $1700. How would you set up your new frame?

LastPlace 09-23-06 10:26 AM

Top Tube.........

Not sure what you mean by 'How would you set up your new frame?' I had planned to simply move the components from my Soma frame to the Pilot.........if I can scrape up the money. I'm thinking I would buy a 54cm Pilot SPA to make for a shorter top tube and a more upright riding position.

I rented a Trek Pilot a couple of weeks ago and thought it was a great ride, especially in light of my age/injury issues.

Sorry for not replying sooner but my work takes me out of town a bit.

Richard Cranium 09-23-06 12:14 PM


With all other things being equal, would a shorter top tube give me a more upright riding position?
No, it would give you a "broken frame".... Assuming the other frame members/angles were adjusted for a change of top tubes you could end up with a longer wheel-base bicycle with a very forward center of gravity.

You win the "Richard Cranium" Post Of The Month Award for managing to take a normal subject like bicycle-fit and present it in such an abs-backwords, totally "Richard Cranium format." Thanks to all the others, you make the Internet proud.

Cadillac 09-23-06 03:36 PM

Avoid a shorter top tube.
Avoid a longer top tube.
Avoid a standard top tube.

Any one of these could be hazardous to your riding comfort.
Don't buy a bike that might have a shorter top tube because you think it would give you a better riding position.
Instead, get a bike that is properly fitted to your body.
Too many people suppose that if they can straddle the top tube, the bike is the right size.
However, your upper torso may be long or short; your arms may be long or short, etc.
All of these factors need to be determined.
Go to a good bike shop and ask to be fitted for a bike.
If they say something like, "Well, you're 6 foot tall, so you should have a 57 cm bike," then walk/run out of that shop.
Get to a shop that will do a thorough sizing.
Any other kind of bike is no better than "tolerable," but not comfortable.

CrossChain 09-23-06 04:26 PM

Don't you wish there were an absolute frame fitting system to which all subscribed and which all agreed was the Ultimate Truth? There are many fitting systems, many points of view on what's comfortable and efficient. There are some general truths, but often they are "adjusted" for eccentric or particular needs. Certainly wise to look at some different fit systems and try some different adjustments. Zeroing in fit is, after some education in what others think, still an individual's set of choices for what works for oneself and one's body, needs, and style of riding.

I believe the OP just queried if all things were equal..........and simply wanted an answer to that question...not a lecture. And I admit to offering as many lectures as anybody else here.

*** Rumors that R. Cranium may be a human are only partially true.

LastPlace 09-23-06 09:29 PM

Top Tube............

Thanks. If I can afford a new frame I will check out the sizing more carefully. My 54cm Trek 1200 fit well enough and my new 56cm Soma also fits well and you were correct in that I was asking a theoretical question.

As for lectures, I probably need a lot more, along with more riding time.

jazzy_cyclist 09-25-06 09:33 AM


Originally Posted by LastPlace
With all other things being equal, would a shorter top tube give me a more upright riding position?
Any thoughts?

Generally speaking, yes. But there are lots of "other things" to consider, e.g., head tube length, head tube and seat tube angles, stem length and rise. All of these can also contribute to upright-ness. Do a test ride.

LastPlace 09-25-06 10:42 AM

Top Tube..........

Thanks for the input. As I said, this all depends on scraping up 2k for the Trek Pilot frame. If I can do that, it will just be deciding betweek the 54cm and the 56cm. The 56cm I rode was fine and helped me understand why everybody; well almost everybody, raves about carbon. Thanks again.

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