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View Full Version : A question for you folks who prefer larger frames...


EPOJoe
02-08-2004, 10:54 PM
I know there are quite a few folks on the forum here who eschew the old concept of riding the smallest possible frame that fits in favor of larger frames. Having always ridden tiny frames with looong seat posts in the past, I’ve recently found myself preferring larger frames as well. I was just wondering; how big is “too” big? Do you insist on a certain amount of standover clearance? A certain amount of seat post exposed? Interestingly, I was recently viewing a copy of “Stars and Watercarriers”, the 1986 Giro d’Italia documentary and noticed that, during that particular time period, the racers were all using large frames with very little seat post exposed.

dbrk
02-09-2004, 08:25 AM
There is no feature of a frame of less significance than stand over height. I stand just under 5'10 with a PBH of 84.6 or so---so I'm not tall and a bit long in the leg. I prefer a top tube of 57-58cm because as bikes get bigger the effective top tube gets shorter!! Keep this in mind!!

Most shops (and three Serotta fitters) try to put me on 56-57cm.

It's not as simple as sizing up _any_ frame because of pedal/knee position (I like to be behind the spindle quite a bit). But, honestly, it's not easy to find a fitter who really understands the French fit that contrasts so vividly with modern race bike notions (which dominate the look we see now, and the compromises to that theory that create the risers, spacers, ht extensions, etc.).

But to answer your question. All of my new bikes are 60cm c-c (some as much as 61.5c-t); top tubes are usually 57-58. If I use 23c tires and have a drop of 7.5 or 8, I can easily stand over a 61 and not touch the toptube.

This will meet with skepticism but so long as you don't need to lean the bike to stand over it, it's not too tall. How's dem'apples? It will feel unusual to most who ride small frames to make the switch, some will never like it, that's no big deal. It's not a matter of better or worse. What's at stake is that there are _different_ ways to fit and to ride bikes. The American tradition of fit and its evolution since the emphasis on marketing turned more and more to light, fast, ride-like-Lance (euphemism, ed. note) has, imho, very little clue about these other fit notions and traditions. If you went to Paris today, M. Csuka would fit you like I was fit: 60cm frame for my five foot nine-ish self. Mike Barry of Mariposa in Toronto understands everything about every possible bike fit (and speaks English!). So there's still some place to go in North America to find traditions and views that add to the current body of dogmas ("OUR fit is the BEST/only/THE way to fit a bike..." which is pure tripe.)

If you look at race bikes from Herse and Singer, for example, you find that they didn't compromise their fit issues to meet the needs of fast riding. These guys fit folks to ride long, long distances in the optimal position for comfort. They focused on "Trials" riding where the reliability of the bike was important because the bike was rated as well as the rider over very long distances. Trials were something like what we see today as modern randonneuring.

dbrk

eddief
02-09-2004, 09:40 AM
I am 5'11" and have a pubic bone height of 84. I, like dbrk, now ride frames with 57-58 top tubes. The Waterford I am selling has a 59 top tube. It was darn comfortable, but not as nice as the new Rex. Again, like dbrk, it appears I am more comfortable with the knees a bit further behind spindle and the new frame achieved this with slacker seat tube and moving the saddle back to the limit of the rails. I think I have this right...that with a tall headtube the effective length of the top tube (reach)is reduced due to the bars coming back at you the higher up in the plane of the head tube they are mounted. Try it, you might like it.

BigMac
02-09-2004, 03:22 PM
The sizing down is not an "old concept", relatively speaking, this is something that was spawned in maybe late 80's-early 90's. Like dbrk notes, its a bad concept devoid of any relevence. Similarly, standover height is completely meaningless. In fact ST length is pretty meaningless, imo.

I suggest you choose frame size primarily on TT length and ST angle. Next, consider front-center, trail and cs length. In almost all situations, a properly fitted frame using just these parameters will result in a "fistfull" of seatpost exposure. If you are uncomfortable with this look or fit, consider ordering your Serotta with a slight upslope TT, most models include custom sizing afterall. Anything more than a fistfull of seatpost is a frame that is generally too small. Its easier to raise or lower bar elevation on a properly sized frame than on a frame that is too small.

Ride on!

Ken Robb
02-09-2004, 04:03 PM
I've been very uncomfortable on bikes 57 c-c that were deemed by fitters to be "perfect" for me. My hands went numb and my neck felt terrible. I ride bikes that are 60 to 62 cm c-c with saddles and bars about even and the comfort is good for longer rides and I can really use the drops for more than a 30 second sprint. I'm 6'1 89.5 pbh, 79cm saddle height. I don't even need padded gloves anymore. about a fistful of seatpost showing. Often 700x28mm tires too to make them even taller. I have ridden 65cm loaners and wasn't uncomfortable thought there was almost no seatpost showing and I did have to tilt the bike from verticle for standover clearance. So what?

jeffg
02-09-2004, 04:32 PM
Well, I don't think of myself as one who prefers larger frames; however, I am 5'9" and generally ride 55 or 56X57. My fit through Serotta ended up with a more compact design, thus the ST length is irrelevant. My other bike is 55X57 and has just a fistfull of seatpost. Thus, while Kelly did recommend a sloping TT for me, it was not necessary on a 56cm frame. My inseam is about 83cm and the standover on a 56 is about 81 cm. It took a bit of adjustment moving from the longer seat post (i.e. more standover) of the Serotta to my other steed. Both, however, handle beautifully. The upside to the sloper is that the HT extension is less. On the other hand, the extension on the level TT frame is reasonable and avoids the slope. It depends what you need. Once you set the important parameters (as BigMac suggests), then decide whether you prefer a slight slope to the TT or a HT extension in the event you need one. I would say, however, that I do prefer at least some standover. I can't really say why, but it does feel better when leaning the bike aggressively in a turn.


best,

Jeff

Kevin
02-09-2004, 07:21 PM
I agree with BigMac. The most important measurements are STA and TT length, most of the other dimensions are dependent upon either cosmetic or handling preferences. The most important one being whether or not you want a sloped TT.

Kevin

EPOJoe
02-10-2004, 12:16 AM
Thanks much for the responses guys, and the sage advice. I have to admit, one of the best rides I've experienced was on Sax's old CSI, which I did, indeed, have to tilt sideways to standover. I wouldn't target something that large as my ideal ride, but I've certainly slid into the "fistful of seatpost" camp.