Author Topic: Advice re Trek 520 frame size  (Read 15431 times)

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Offline RidersToTheSea

Advice re Trek 520 frame size
« on: February 19, 2007, 08:11:52 pm »
Just looking for advice on frame size..... I'm 6'1.5"  (73.5inches). My
inner seam length is 34.5 inches.

I'm looking to order a Trek 520 from my local Trek dealer and want to
be sure I get the best frame size.

The shop suggested a 23" frame for my height. However, they were not
familiar with this bike and their approach seemed dissinterested.  
They dont have a Trek 520 in stock and will take 2 weeks to order. I
wont be able to try a model out for size in the shop before ordering.

I have checked the Trek website and it recommends a 25" frame for a
74" height rider (I'm 73.5).

Does anybody have advice on which frame size I should go for? Any
other tall 520 riders out there?

Mant thanks

Offline driftlessregion

Advice re Trek 520 frame size
« Reply #1 on: February 19, 2007, 11:00:06 pm »
You would be well served to find a shop that can do a professional bike fit. That is the best way to determine not only the size of the frame but how the saddle, cleats and bars are set up. If they don't know how to put you on the right sized frame or ask what type of riding you will be doing, leave. It's too important a task to ignore.  A setup for a tourist is different from one for fast club rides etc. The age of the rider is also a factor as older riders have more difficulty in aero positions. You can go to a pro shop and have the fit and take the data to the Trek shop if need be. I guarantee that yo won't be disappointed in paying the money for a proper fit! (It is worth it for anyone even if they aren't buying a new frame.)  That said, I think a 25" frame is about right, perhaps 24" if you're young.


  • Guest
Advice re Trek 520 frame size
« Reply #2 on: February 20, 2007, 12:58:49 am »
A larger frame (within reason) allows you to stretch out a little and gives you more toe and heel clearance with panniers.  Touring bikes should be a tad bigger than road bikes for the same person.  

Offline DaveB

Advice re Trek 520 frame size
« Reply #3 on: February 20, 2007, 09:58:08 am »
One rough but quite effective method for choosing frame size is "stand over height", i.e. the distance from the ground to the top of the top tube.  For the 560 Trek gives 31.7" (80.6 cm) for the 23" frame and 33.5" (85.2 cm) for the 25" frame.  

Measure your "bike inseam" (not your pants inseam) by standing with your back against a wall in your stocking feet with your feet about 10" or so apart.  Push a moderately thick book, spine up, between your legs until it meets firm resistance.  Measure the disstance from the floor to where the top of the book hits the wall.  That's your bike inseam.  Compare that distance to the standover height.  The stand over height should be at least 1" less than your inseam measurements.

Unless your legs are abnormally long or short for your overall height, this is a good starting point.        

If the inseam of 34.5" you gave was measured this way, the 25" frame just makes it and will allow you to get the bars relatively high which is desirable for touring.  

I hope your dealer will work with you to get the stem length and bar position that are comfortable.  It sounds like they aren't familiar with Touring bikes at all and tried to size you based on sports or race bike fit.        

Offline RussellSeaton

Advice re Trek 520 frame size
« Reply #4 on: February 20, 2007, 01:31:07 pm »
I'm a 5'11" man.  33.5" inseam measured the official cycling way.  Average body proportions.  I had a 21" Trek 520 frame.  1991 vintage.  I think Trek 520 sizing has stayed the same for decades.  21" frame was too small.  I needed at least the 23" frame.  And even then it would still be a bit too short given its frame size and my preferred top tube length on my road bikes.  I would definitely suggest the 25" if you are 6'1" or so.

Best way to get a proper fitting bike is to determine what size bike you are riding now and see if its right or not based on the thousands of miles you've ridden it.  Professional fittings are just guesses based on the fitter or database they are using.  Nothing beats your own experience.  If you can comfortably ride hundreds of miles a day, then the fit is probably pretty close.  Whereas if you are uncomfortable riding 100 miles a day, then the fit needs to be adjusted from what you currently have.  If you have no road bike to compare with, then you need to jump in somewhere, and an average bike based on 1" or so of standover for your height, given you are average body proportions, is as good a place as anywhere else to start.


  • Guest
Advice re Trek 520 frame size
« Reply #5 on: March 19, 2007, 06:49:14 pm »
I am 6'2 1/2" and the 25 is too small for me.  My LBS almost sold me a 23.  In order to get the handlebars to the height of the saddle I use a stem extender.

Offline RidersToTheSea

Advice re Trek 520 frame size
« Reply #6 on: March 23, 2007, 02:12:29 pm »
I picked up my shiny new Trek 520 25" last week - I got the LBS to change over the inner chainring. Thanks for all the advice folks.

I can identify with your comments Timber, a lot of the bike shops I went to suggested a 23" - turns out it would have been too small.

Anyway...enough chat for now... I'm off to get some saddle time in - (which reminds me of one more thing I have to change).