Originally Posted by
wrk101
Well, the construction has changed quite a bit from the era of the 412. I have a 1981 Trek 412 and a 1983 Trek 520. Both are 22 1/2 inch frames, measured from the center of the bottom bracket to the top of the seat tube. As you can see in my two pictures, the seat tube does not extend past the top tube. Also, my 22 1/2 inch frame 412 has a standover of 32 1/2 inches.
I sold a 1983 Trek 620 last week, with a 24 inch frame size. The standover was over 34 inches. I can't imagine if the OP has a 33 inch bike inseam that he could fit a 25 1/2 inch frame.
The 412 was last made in 1982. As all bikes of that era, it had a quill stem.
The blue bike is the 520.
Quill is good! Seriously. Threadless has its points (all of which I acknowlege) but unless you want the bars just above headstem height, it offers all sorts of compromises and inabilities - for example, once you start using 35 degree stems like I do, any change in length changes reach and height, too bad if you only want to change one not the other, and the choices of stem are limited. But the OP's 412 has a quill.
As for Trek and it's bikes. My 520 is the 2007 model, the last that had Ultegra shifters (bar end shifters offered as an alternative) and the like. Really, it feels like a bike made by a company that doesn't really care but keeps churning them out because they've got a good name based on past glories and some of the daft things they've done make you wonder if Trek themselves ever tried to use one. Then there was Trek's lack of interest in actually selling me the stupid thing. Sheesh.
But enough grumbling.
With the 412 coming with a quill, the OP's only concern is the reach - he can opt for a lot of standover or not very much depending on taste. Even reach is relatively easy to deal with though that involves buying new quills. Cripes, reach can even be affected by the handlebars that are fitted ... or the position of the brake levers if using drop bars ... but again, they're easy to change.
Realistically, sizing a frame can only be done by riding the bike in question. Buying based on numbers is so fraught with drama and potential for disaster that it should only be attempted by those (like me apparently) who love getting it wrong. Part of this is the love of manufacturers to change things and marketing men to offer all sorts of weird measuring systems in the interests of confusion and bling, but a large part of it is how our bodies operate. For example, I recently spoke about having to change my seat height dramatically - part of that was a change in hardware but associated with it seems to be a change in the way I ride, not appreciated until I tried to work out what was going on. You might have long legs but ride with your heel low demanding a lower seat height to someone who rides pointing their toes. You might be quite happy with low handlebars but you might be like me who needs them high. Your torso might be longer proportional to your body than the norm (like me again) thus enabling you to get away with a longer reach. And the forgotten point, as you get fitter or your body wears out, your fit changes.
But I'm just offering random thoughts and grumps because I'm supposed to be working and would rather be talking about bikes.
Bah humbug.
Where's my coffee?
Richard