Touring - Please help with bike sizing

I had to order a Trek 520 because my LBS won't stock them. 520's are measured in inches in the Trek brochure. I have a 29.5" inseam so I ordered a 19" 520 with a 28.6" standover. NOW I find out that a 19" 520 is a 48 cm frame. I'm afraid it might be too small.

Anyway, here's my question... is it better with a touring bike to error on the small size like it is with a MTB? I'm thinking it's easier to make a small bike fit you than a large one. Comments?

I have a 30.5" inseam (at 5'8" tall) and have a 21" Trek 520. The bike is a little short in the top tube, but the stock stem had the right length but not enough rise. I now have another stem with same length but more rise. Now the bike fits me perfectly for loaded touring.

Whether or not the 19" will fit you sort of depends on your upper body length and if there's a stem that will accomodate. I think the 21" (the next size after the 19") has about a 31" standover, so that might have been uncomfortbly tall, whereas you have a little clearance with the 19".

For standover, you have to factor in the bottom bracket height as well as the seat-tube length.
More significant is the top tube length. If you know the reach you need, then a combination of TT and stem length can get you there.

There is very little difference in standover between 17" and 19" and 21" frames. I'd suggest you look at Trek's website for standover height and top tube length and try to find a similar fit on a different bike. A hybrid with similar sizing could tell you whether the 21" would fit or not.

I had to order a Trek 520 because my LBS won't stock them. 520's are measured in inches in the Trek brochure. I have a 29.5" inseam so I ordered a 19" 520 with a 28.6" standover. NOW I find out that a 19" 520 is a 48 cm frame. I'm afraid it might be too small.

Anyway, here's my question... is it better with a touring bike to error on the small size like it is with a MTB? I'm thinking it's easier to make a small bike fit you than a large one. Comments?
Hi Tdub. I'm the same as Bradw, With an inseam of 30" and I got the 21' frame. Trek's frame is measured C-T, with that measure yourself standing flatfoot on the floor place a broom handle or simular item between your legs and snug up a little into the crotch with your feet @6"apart, have someone measure the distance from the floor to the bottom of broom handle that's your correct inseam lenght (don't use your pants inseam). Then with your bicycle shoes on, and on the bike that should give you @2-3" of comfortable standover height, You don't want to have no clearance at all when you're waiting for a long traffic light and both feet on the ground. As long as you can adjust the seat height correctly with the bars level or a little above the seat height then that will be very comfortable on long tour's. I too had to get a different stem for height, because I like to tour a little more upright than a racer.( Your LBS should fit you when the bike comes, even after you ride the stem for a while they should still be willing to swap-out, until you find the right one). Anyway check your inseam, it might not be too late to change the bike size.
James

Thanks James,
I measured my inseam using your method and that's how I came up with the 29.5 inches. I've ridden the bike for just a minute and I can tell the seat will be well above the bars (2 inches maybe).

They offered the bike to me at $800 so I put it on layaway. I guess I'll adjust the fit by swapping the stem as you suggested.

The 520 should be sized using road bike sizing not mountain bike sizing. More important than the stand over height is the top tube length. Because of it's relaxed geometry the 520's top tube is shorter than that of sport touring or racing bikes the same size. If the top tube is too short for you there is some adjustability using longer stems. But this only goes so far. Stem swaps are used for fine tuning not major adjustments. If the bike is too short for you this is an issue you need to settle before you take delivery. If the bike doesn't fit have the shop order the correct size. This isn't a problem for a reputable shop.

The 520 should be sized using road bike sizing not mountain bike sizing. More important than the stand over height is the top tube length. Because of it's relaxed geometry the 520's top tube is shorter than that of sport touring or racing bikes the same size. If the top tube is too short for you there is some adjustability using longer stems. But this only goes so far. Stem swaps are used for fine tuning not major adjustments. If the bike is too short for you this is an issue you need to settle before you take delivery. If the bike doesn't fit have the shop order the correct size. This isn't a problem for a reputable shop.

Hi Tom, I think you got that reversed, My top tube on the trek 520 is 22" (C-C) rather long, thats on a 21" bike, the 520's made for touring, long top tube, long chain stay. My mountain bike or back roads tourer is considerably shorter (21" C-T frame). The stem takes care of the rest which is very fine tuneable from 0-120 cm's, some mfg's even more.

Thanks James,
I measured my inseam using your method and that's how I came up with the 29.5 inches. I've ridden the bike for just a minute and I can tell the seat will be well above the bars (2 inches maybe).

They offered the bike to me at $800 so I put it on layaway. I guess I'll adjust the fit by swapping the stem as you suggested.

Hi Tdub, Not the seat...You'll want the handlebars, even, or a little above the seat for comfy touring. You just don't want to maintain a horizontal torso for long tours, gets very uncomfy, Unless your Lance (The Man) Armstrong.

Go...Lance.....Go......2004....TDF

Hi Tom, I think you got that reversed, My top tube on the trek 520 is 22" (C-C) rather long, thats on a 21" bike, the 520's made for touring, long top tube, long chain stay. My mountain bike or back roads tourer is considerably shorter (21" C-T frame). The stem takes care of the rest which is very fine tuneable from 0-120 cm's, some mfg's even more.

I don't have it backwards. Look at Trek's spec charts and you'll see that the 520's top tube is shorter than that of it's sport tourers or racing frames. At least on sizes of 58cm and larger. On the 520, other than being able to touch the ground without crushing the family jewels, standover height is meaningless. With the 520 it's all about top tube length. If you size the bike using one of Trek's road bikes as a guide you're gonna come up short. Mountain bike geometry is moot.

I looked up the top tube lengths on the trek website. Numbers are for '04 models.

23" 520 has a 56.6cm / 22.3 " top tube.

I used the recreation/road bike line of 1000/1200/1500 (triple crank/drop bar):

58cm has a 57.3cm /22.5" top tube

Not much difference.

If you want to look up other models:

http://www.trekbikes.com/bikes/2004/pdf/2004_geometry_en.pdf

I don't have it backwards. Look at Trek's spec charts and you'll see that the 520's top tube is shorter than that of it's sport tourers or racing frames. At least on sizes of 58cm and larger. On the 520, other than being able to touch the ground without crushing the family jewels, standover height is meaningless. With the 520 it's all about top tube length. If you size the bike using one of Trek's road bikes as a guide you're gonna come up short. Mountain bike geometry is moot.

No idea where you're coming from, my tech (2003 & 2004) sheet show's no other frame in the road or racing longer than the 520's top tube, size for size. (Don't think I want to tour on a Fuel 100 or Liquid 30, however, wouldn't mind trying the Woody 23" TT, but where would my panniers go?). On the other matter, maybe we should start a new thread about standover height for Tourer's, I've been touring for over 30 years on a bicycle, and I don't believe many would like to be waiting at a traffic light, on one foot
with the TT in their crotch fully loaded. Stand over height is very important, and Trek addressed that very well. One more important factor is wheel base, at 41.5" it's a winner. Now if you're a racer this is N/A for you. IMOA

No idea where you're coming from, my tech (2003 & 2004) sheet show's no other frame in the road or racing longer than the 520's top tube, size for size. (Don't think I want to tour on a Fuel 100 or Liquid 30, however, wouldn't mind trying the Woody 23" TT, but where would my panniers go?). On the other matter, maybe we should start a new thread about standover height for Tourer's, I've been touring for over 30 years on a bicycle, and I don't believe many would like to be waiting at a traffic light, on one foot
with the TT in their crotch fully loaded. Stand over height is very important, and Trek addressed that very well. One more important factor is wheel base, at 41.5" it's a winner. Now if you're a racer this is N/A for you. IMOA



Where I'm coming from is Trek's own spec sheets and 16 years of 520 ownership.
The intent of my original post was to make sure that the person asking for help was aware that sizing for the 520 is different than it is for much of Trek's road bike product line. I did that. I also wanted this inexperienced person to know that many bike shops will try to cover up a sizing error with the use of extended stems, seat posts etc and that asking the shop to order the right size bike is normal course of business for an honest shop. I did that.
I really don't care what your opinions are about sizing. It's off topic. Now let's drop it and move on.

Try this http://www.bsn.com/Cycling/ergobike.html