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Front page poll-if you have a TREK do you go by c-t, or TREK(26 posts)

Front page poll-if you have a TREK do you go by c-t, or TREKjtferraro
May 21, 2003 10:08 AM
size? As many of you know, they measure frame size by center of bb to top of seat tube. I submitted my vote based upon the c-t, NOT my TREK size (since they are the only ones using that system, I think).

Just curious...not that it matters that much, except for more accurate results.

Damn - I didn't even know that and I have a Trek!! (nm)Rich_Racer
May 21, 2003 10:34 AM
The way it is is fine...Fez
May 21, 2003 11:00 AM
I think the reason Trek measures all the way to the collar is because the other dimensions, especially top tube, are comparable to what you would find when shopping the competition, like Cannondale or Litespeed (odd # size).

Think of a Trek as true to the listed size, with a tad bit more standover than the competition due to the lower top tube.

Lots of people erroneously say Treks have long top tubes. This is wrong because they tell you to buy 1 size larger than the listed size because they completely ignore the center to top of seat collar measurement.
Interesting but that would suggest very short head & seat tubes.Eug
May 21, 2003 11:41 AM
I measured my so-called 54 cm Trek, and in the centre of the seat tube, the seat collar is only about 1.7 cm above the top of the top tube. (The seat collar is 1.3 cm thick.) Furthermore the curve of the weld for the top tube on the seat tube meets the bottom of the seat collar.

Similarly, the curve of the weld of the top tube at the front almost meets the top of the head tube.

Thus, it would be impossible to raise the top tube, unless:

1) Treks increased their seat tube length, and
2) Treks increased their head tube length.

Are you saying that Treks have unusually short seat tubes and head tubes? If so, why would they do that?
No, and yes.Fez
May 21, 2003 12:18 PM
The published seat tube length is somewhat irrelevant. In practice, a seat tube is commonly measured C-C, C-T, or C-very top of the seat collar. The first 2 methods are slightly affected by tube thickness. The last method, measured to the top of the collar, is affected by how short or tall the manufacturer wants to build the collar.

But you are absolutely correct that Treks do tend to have short head tubes. That could explain how Trek was able to achieve a little more standover clearance. Unfortunately, it also may require an extra spacer or 2 to get the bars at the correct height.
54 cm Trek = 52.5 cm C-T? Either way, probably slightly too big.Eug
May 21, 2003 11:09 AM
I can't remember to what my Trek's 54 cm size corresponds. 52.5 cm C-T?

I'm still thinking my 54 cm Trek is a little big for me. 5'7" 30.75"ish inseam. ie. Longish legs. Shortish torso. I've got a good chunk of seatpost showing, but I'm running a 60 mm stem now to make it feel comfortable.
Why are you on a Trek w/ your proportions?kenyee
May 21, 2003 1:36 PM
If you're really long leg/short torso, Treks shouldn't work very well. They're for long torso/short leg folks...

Because this was my first road bike...Eug
May 21, 2003 2:46 PM
...and I didn't know any better.

Plus it was cheap. Maybe if I get into better shape I'll just sell it and get a new one.
Can't be more wrong. Lance for example has longish legselviento
May 21, 2003 3:54 PM
Trek calls the design "racing geometry", ie, more stretched out and lower standover. Perfect for racers.

Many pros get longer toptubes and lower standovers by getting custom made bikes (Bartoli, McEwen, etc. too many to list).

But Trek's carbon manufacturing process doesn't allow this. So their stock model is already long and low. This may not be perfect for someone not ready/willing to go that low, but it doesn't seem to have slowed Trek's sales a bit.

If you want a Trek but want a proper sized stem: Go with their nomical size and get lots of SPACERS!
love that SHIMANO decal...C-40
May 22, 2003 4:55 AM
On a Campy Record equipped bike. Can you get that thing off?

Nice bike, otherwise.
Nice! What does it weight? Also, what size frame? (nm)jtferraro
May 22, 2003 6:14 AM
Sure he could.djg
May 22, 2003 1:00 PM
The OCLVs--relative to most road bikes off-the-peg, have rather long top tubes given the actual (not nominal) length of their seat tubes. I had a 5200 for about a year and a half. It was a nominal "56." The seat tube, measured in everyday c-t terms was pretty darn close to 54 cm. That's not really the classic square measure in my book. Of course that CAN work for a person with longish legs (for his or her hight). It can work if the person doesn't mind a bunch of spacers. Or it can work if the person tends to like bikes, as you say, long and low. But it seems pretty darn obvious to me that it's not crazy for the poster who "couldn't be more wrong" to suggest that people who, at a given height, have longer than usual legs and shorter than usual torsos will not tend to look for bikes with longer than usual top tubes.

Trek's sales are great in part because OCLVs are pretty nice bikes, but in no small part because of the Lance/Marketing + distribution machine. It's not because they fit everybody. Some folks fit them great. Some folks fit them just fine, with extra spacers. And lots of folks buy them without a clue about fit (and sometimes from shops that don't have much more of a clue).
Why are you on a Trek w/ your proportions?deHonc
May 21, 2003 4:31 PM

I don't agree - I have long legs/average torso - Trek OCLV fits me perfectly - in fact, I had a Brisbane custom builder size me up and once I had done this I found out that a 60cm Trek would be exactly right for me - so I bought one and its pure comfort - poetry in motion!

Go by the top tube...James OCLV
May 21, 2003 5:25 PM
Who cares about standover height - the really important measurement is top tube length. I'm 5'7 with a 31.5 inseam. Based on this inseam measurement, I ordered a 52cm Trek OCLV. Well, the top tube was way too short, and I ended up running a 130mm stem to compensate. I was recently fit on a Serotta size cycle, and according to the fit I should ride a bike with a 52cm c-c seat tube and a 54cm top tube. I sold my 52cm and ordered a 54cm OCLV. I now run a 110mm stem, and the bike fits me perfectly.

Lance's caloi was a 56cm - he now rides a 58cm OCLV...
Maybe I'll grow into my 54...Eug
May 21, 2003 7:34 PM
Hmmm... Maybe I'll get more used to my 54 cm.

I don't see myself ever using a stem longer than 90 mm though with this frame. (I can reach with the stock 85 mm just fine, but only with a very aggressive position which is tough on my neck.)
stem size?kenyee
May 21, 2003 6:16 PM
I'm puzzled. Eug's stem size of 60mm seems to confirm that the TT is too long for him, right?

I looked at Treks a while back and it seemed like I'd need lots of seat post to match the TT I'd need and then I'd have to worry about a steep bar drop unless I used a lot of spacers...

Don't use me as a guage. I'm a road bike n00b...Eug
May 21, 2003 7:26 PM
I definitely do not have an aggressive reach at this point. Remember I'm just an out-of-shape mountain biker. Perhaps the bike would suit others much better, even with shortish torsos.

eg. The 5'7" guy with 31.5" inseam seems to love his 54 cm OCLV.
2 thingsFez
May 22, 2003 5:39 AM
You said you were an "out of shape Mtn biker." If this is your first road bike, you need time to get used to the longer and lower reach. If you are out of shape, you will find over time you will be able to stretch out and get lower.

Did you check saddle position? I hope you don't have the seat 2-4cm back further than it should be and then wonder why you need a short stem.

1. Get saddle position dialed in. Then get a stem that is comfortable. Ride a few months/few thousand miles. Your position will evolve a bit and you will get stronger. Revisit stem and bar positioning again as you progress.

2. Based on the info you gave (but not having seen you), the 54 OCLV is definitely in the ballpark for you. The 52 has a steeper seat angle so the effective top tube is only going to be less than 0.5cm shorter than the 54. What you really would notice with the 52 is even lower standover and a lower head tube.

Hope this helps
hmm...the FAQ should take this into consideration tookenyee
May 22, 2003 6:04 AM
Assuming there are racer types who are fit and those who are older or less fit, there are different bikes that fit "short torsoes".

Sounds like the Treks work fine for short torsoed folks, but are for folks who can get lower (seat to bar drop > 1-2"?). I.e., folks who spend lots of time in the saddle and/or race.

If you're not that fit or a bit older w/ less flexibility or a roadie newbie, you'll be more comfortable w/ a "Rivendell" fit of 0-1" seat to bar drop. Maybe a list of bike companies that have relatively long head tubes would be more useful: Pegoretti, Rivendell, etc.

Now we have to define "short torso" :-)
stem size?James OCLV
May 22, 2003 8:34 AM
Off the cuff, I would say that yes, in his case the TT may be too long. A lot of bike "fit" also has to do with your degree of flexability. I find that most cyclists that I fit don't rock their pelvis forward enough as well. You should try and mimic the "ready" position of other sports on the bike. This will help with your power generation as well (brings your glutes into play on the top of the downstroke), and I've also found it to relieve some "numbness" in the nether regions...

As far as a lot of spacers go, you can get a 10 degree stem and flip it... That will give you a less-agressive position.
rocking pelvis?kenyee
May 22, 2003 9:27 AM
Could you elaborate on this? The only time I've heard this is when setting the saddle height: you know it's too high if you have to rock your pelvis to peddle.


rocking pelvis?James OCLV
May 22, 2003 11:35 AM
Hi, sorry for the confusion... I should have said to tilt forward from your pelvis; I didn't mean rocking it side-to-side.

To illustrate this, sit in a chair with your feet flat on the floor and the small of your back against the backrest. Rest your hands on your knees and relax. Now, without using anything but your legs, try and stand up. It should be hard if you can do it at all.

Now, tilt your pelvis forward so that your spine is in a straight line and the small of your back is no longer arched (should automatically come away from the backrest of the chair when doing this). From there, bend at the waist. Now, try and stand up - should be much easier.

This is the position you should strive for on the bike.
but isn't your pelvis angled like that on a road bike already?kenyee
May 22, 2003 12:28 PM
Even on an MTB, wouldn't your pelvis be tilted forward at the top if you're holding on the handlebars unless you're inverse arching your back which probably isn't good for you?

I think the chair thing positions your upper body's center of mass over your lift point, but if you keep your back against the backrest, it's behind your life point, so you end up pushing the chair backwards and falling over :-)
but isn't your pelvis angled like that on a road bike already?James OCLV
May 22, 2003 12:33 PM
You'd be surprised, but it's how A LOT of people ride. Especially those with poor flexability. They'll sit like that, and try to reach the bars, wich in turn puts stress on their neck and shoulders. I rotate them forward, and there's in most cases an immediate increase in power (not to mention comfort).
but isn't your pelvis angled like that on a road bike already?James OCLV
May 22, 2003 12:39 PM
Oh, I forgot to mention, in the chair example, at the point where you have the small of your back against the backrest of the chair, just lean forward without changing the position of your pelvis (with your torso parallel to your legs). You can't stand...

Stay in the same position and tilt your pelvis forward. Notice the difference...
May 22, 2003 2:31 PM
That was an interesting discussion.

BTW, when I try getting up w/ the back against the chair, I get up and fall backwards. It's pretty funny :-)