Bicycle Mechanics - Putting ATB Gearing on a Trek 520

PART I - I'm getting tremendously mixed information about changing out my Shimano 105 Crankset (30/42/52t) for an ATB Crankset (something like 26/38/48, Shimano Deor LX or XT, etc).

I have a Trek 520 (http://www2.trekbikes.com/Bikes/Specialty_Bikes/Touring/520/index.php) (approximately model year 2002) that I'm going to use for an unsupported 3 week tour this summer. Due to recent knee surgery, I'm working hard to keep my cadence up and thus want some easier gears. Ideally I'd get my lowest gear down to about 20 gear inches.

I've had people tell me "No problem, just switch out your 30t chainring for a 26t" all the way out to "no way man, that bike can't even handle ATB gearing".

I don't really care if I can't comfortably get into my Small-Small gear, but I definitely want to be able to into Small front-Big back and most others.

Currently my cassette is a 11/32, which I'd like to switch out to a 12/34.

Can anyone give me a clear answer as to whether this is even possible?

I'm assuming that I'll have to put on an ATB front derailleur too?

PART II - Can anyone suggest a bike shop they trust in the Seattle, WA area.

Thanks very much!

Cranky in Seattle

The Deore crank works.You will need the matching BB.The Road FD will probably work with the mtb rings you mentioned.The RD will handle a 34. Your cheap fix for the crank would just be a 26 instead of the 30 granny.

Switching to mtb drivetrain is done all the time, especially on touring bikes such as your's. Your current 105 road FD should be able to handle the crankset swap, no problem.

You may even be able to drop to 24-36-46 or 24-38-46. 46/12 = 103.5 gear-inches, is still a good high top gear, in my book.