Author Topic: Trek 520  (Read 23764 times)

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Offline digimarket

Re: Trek 520
« Reply #15 on: July 27, 2010, 12:19:19 am »
I believe the problem with discussions of front end geometry is that people are using words like stable, quick and twitchy without a specified definition.

It is my feeling that "quick" steering means that when you turn the handlbars - the bike responds quickly without having to turn the bars a lot.  This is the opposite of "light" steering - in fact this steering has a significant "weight" to it - the force required to act through the lever arm of trail against the forward momentum of the bike and rider.  This longer trail lever arm is what makes the bike move out from under the cyclist quickly - so you can establish your lean and turn angle and get on with the business of cornering.

What I experienced with the bikes (several of the bikes I've owned over the years had what I considered excessive fork offset - therefore insufficient trail) i considered "low-trail" was that it was easy to turn the bars - but not very much happened.  I would approach a high-speed downhil curve - and have to turn the bars a lot to get any response, then once the lean was finally acquired - there was an overshoot and more steering was required to get the proper line.  This didn't make for confident cornering and wouldn't be at all safe with heavy loads.  Bikes with the proper amount of trail just jumped to the line I wanted and stayed there very smoothly and felt like they were "on rails".  All of my bikes with trail in the "mid-range" handled fine, but the ones with low trail were unsettling to corner with.    So I have found good handling bikes with head angles from 74 to 70 (my two 75 degree "road" bikes were not satisfactory) and fork offsets from 38 to 55 that have moderate trail as their shared characteristic.  The bikes that handled the worst were both 73 degree head angles with 55mm fork offsets - very low trail.  Interestingly enough - most of the literature indicates that moderate trail geometry is easier to ride hands off.  So why do some touring bike designers like low trail?  I don't know - maybe they don't ride them themselves, but design them for theoretical tourists with heavy loads in floppy handlebar bags and under-developed bike handling skills.

This link is the best discussion on this subject I have been able to find:http://www.johnforester.com/Articles/BicycleEng/Kvale%20Geometry.pdf
« Last Edit: July 27, 2010, 12:24:39 am by digimarket »
Bertoni Corsa Montadale, Bob Jackson, Viscount all rounder, Styre, Bianchi Boardwalk, Jamis Aurora, Schwinn Cimmaron, Schwinn High Sierra, Humber 3-speed.

Offline whittierider

Re: Trek 520
« Reply #16 on: July 27, 2010, 01:09:07 am »
Quote
most of the literature indicates that moderate trail geometry is easier to ride hands off.

The head tube angle and the fork rake work together to produce trail, and these work together to determine stability.  The Rivendell Reader, issue #31 from Jan '04, had a report on some experiments Rivendell did.  They made a special fork with long horizontal dropouts, so the wheel could be moved forward and back.  They did not have a way to change the head tube angle so easily, but from what they did try, the writer says about trail: "The biggest difference came out in no-hands riding-- the low-trail bikes were easy to ride at low speed, where the tons-o'-trail bikes were hard; and at high speeds it was just the opposite."

Marc Muller, Waterford's designer (although I don't know if he is anymore), speaks of another thing he calls "steering angle," which also brings the wheel size into the equation (which makes sense, since rake and trail have to be relative to the wheel size).  Usually we're only talking about 700c though.

There's also the matter of how far forward from the steering tube you put your hands on the bars (involving the bar reach and the stem length) affecting the handling.  Short stems and bar reach make a bike less stable, without improving the quickness of handling.

Offline playpiano1980

Re: Trek 520
« Reply #17 on: July 27, 2010, 09:23:03 pm »
You are half correct - 73/55 is a very low trail design, but low trail means that the handlebars have to turn a lot to make the bike turn - not good handling.  You can have the bars "twitch" all over the place and nothing happens.

With a high trail design, the bike steers significantly with every "twitch" of the bars.

If you look at a criterium racing bicycle it will have very little fork offset, because the trail is already diminished by the steep angle.  By cutting down on the offset - the designer is actually adding some trail back in to keep the steering quick.  

Take a look at a frame design book if you don't believe me.  I have changed a nasty slow steering "pig" of a sports tourer into a responsive enjoyable ride that carves turns great by replacing the 55mm fork with a 38mm.  (Truth is, I would have prefered a 42, but I still haven't found an affordable one.)

Road touring is great at 72/45.

Replacing the fork can have tremendous benefits, I have a buddy who recently completed this install and loves his bike more than ever. He use to call it "sluggish", and wanted a new bike, now he is happy, and so is his bank account!!
« Last Edit: July 28, 2010, 05:46:11 am by FredHiltz »
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Offline digimarket

Re: Trek 520
« Reply #18 on: February 04, 2017, 04:24:31 am »
This is amusing.  I recently purchased a late model Trek 520 frame to build up into a loaded road tourer and I was searching for people's experience with 520's.  I found this topic and was reading through it, and thinking, "this guy thinks the way I do".  HA!  It is me!  I had totally forgotten about this thread.  I still have my Aurora, and like it a lot but it currently has 32 spoke wheels and rims too narrow for anything over 28mm on it.  I got a deal on the 520 frameset from a guy who had moved all the stock components to a Bruce Gordon.  Just the kind of bike project I like - a bare frameset that I can build to suit me.  When I'm done it won't look much different than a stock 520, but none of the components will be the same.  So far I've collected:  Shimano Deore 36 hole hubs with Velocity Dyad Rims, Serfas Vida 700x38 tires, Planet Bike Hardcore Hybrid Fenders, Nitto Noodle Bars, Cane Creek V levers, Avid SD-7 V brakes, Salmon Cool Stop pads, an old Specialized stem, Performance Pro SL Saddle, Shimano UN55 square taper sealed bottom bracket, old Specialized "strong arm" mountain compact triple crankarms, Race Face 9-speed rings 44x32x20, SRAM 9 speed chain, an old Easton seatpost, Tubus Ergo Lowrider front rack, Lone Peak Sundance front Panniers, the stock Bontrager rear rack, and Ortleib Back Roller Classic bags.  My trusty Zefal HP full size frame pump (don't leave home without it) fits perfectly along the top tube using the stock pump peg.  I'm still debating on the drivetrain.  It will have bar end shifters - either Shimano 9 speed or Silver Shifters , I haven't decided which derailleurs I will finally use, but will start with an old Deore XT on the back and a M900 XTR on the front and see if they can handle the range.  I need to buy a new wide range 9-speed cassette  I've ordered bottle cages for 1.5 liter disposable bottles.  Once it is built, I can do back to back rides with it and the Aurora (switching wheels) and will report on my impressions.  One thing I'm uncertain about is pedals.  I use Look clipless on all of my road bikes, but I don't want to tour/camp in them.  I need to find some wide pedals (with cages and straps) that work really well with trail runners and boots.  I can't go to SPD after resisting for decades - for me that would be going to the dark side.
Bertoni Corsa Montadale, Bob Jackson, Viscount all rounder, Styre, Bianchi Boardwalk, Jamis Aurora, Schwinn Cimmaron, Schwinn High Sierra, Humber 3-speed.

Offline DaveB

Re: Trek 520
« Reply #19 on: February 04, 2017, 09:22:51 am »
You are half correct - 73/55 is a very low trail design, but low trail means that the handlebars have to turn a lot to make the bike turn - not good handling.  You can have the bars "twitch" all over the place and nothing happens.

With a high trail design, the bike steers significantly with every "twitch" of the bars.
Again, I think you have this backwards.  "Trail" is the same as "castor" and controls the self-centering tendency of the front wheel.  A large trail figure tends to keep the front wheel pointed straight ahead and makes turning sluggish but makes high speed stability better.  Low trail is more responsive but requires more attention to keeping the bike in a straight line.

Offline dkoloko

Re: Trek 520
« Reply #20 on: February 04, 2017, 11:57:35 am »
I have a 2015 Trek 520. Best touring bike I've owned. Not had a LHT; numerous comments of truck like performance (rides best loaded). LHT seems to have a cheaper frame to me. Bar end shifters have saved me; switched to friction mode when indexing failed on tour.

If you like the 520, why hesitate? buy it. As for suggestions to test ride both, lots of luck my area. Lucky for a shop to have one touring bike in stock, much less a selection of makes and sizes.

Offline bikemig

Re: Trek 520
« Reply #21 on: February 05, 2017, 01:00:03 pm »
The Trek 520 is a classic touring bike for good reason. If looking to save some money, it's tough to beat the Fuji touring (the '016 and '017) model. It's nicely spec'd and very reasonably priced.

Offline dkoloko

Re: Trek 520
« Reply #22 on: February 05, 2017, 01:23:13 pm »
When I went from a new Fuji touring bike to a Trek 520, my local bike shop, who did not sell me either, said the 520 was better "in every way". Why I would not go that far, I would say, based on my experience, spend the few extra hundred dollars,  buy the Trek.

Offline bikemig

Re: Trek 520
« Reply #23 on: February 05, 2017, 03:45:01 pm »
When I went from a new Fuji touring bike to a Trek 520, my local bike shop, who did not sell me either, said the 520 was better "in every way". Why I would not go that far, I would say, based on my experience, spend the few extra hundred dollars,  buy the Trek.

I've wrenched on my share of bikes over the years and I've examined both bikes pretty closely both online and in person.

A 2017 Trek 520 runs $1360; a 2017 Fuji touring runs $719. That's a whole lot of coin. The Trek has disc brakes which is an advantage. Otherwise the two bikes have a chrome moly frame, deore cranks, deore hubs, deore rear derailleurs, and bar end shifters. The fuji comes stock with vittoria randonneur 700 x 32c tires (pretty nice tires). I have a tough time seeing $600 worth of difference.

Don't get me wrong. I understand why you or the OP might prefer the Trek; it's a famous touring bike. I'm just saying that the Fuji is very comparably spec'd (other than primarily the disc brakes) and costs $600 less.

« Last Edit: February 05, 2017, 03:52:40 pm by bikemig »

Offline dkoloko

Re: Trek 520
« Reply #24 on: February 06, 2017, 10:33:31 am »
When I went from a new Fuji touring bike to a Trek 520, my local bike shop, who did not sell me either, said the 520 was better "in every way". Why I would not go that far, I would say, based on my experience, spend the few extra hundred dollars,  buy the Trek.

I've wrenched on my share of bikes over the years and I've examined both bikes pretty closely both online and in person.

Don't get me wrong. I understand why you or the OP might prefer the Trek; it's a famous touring bike. I'm just saying that the Fuji is very comparably spec'd (other than primarily the disc brakes) and costs $600 less.

I thought so too, about equal, by looking. After use, not so much; but, if cost is absolutely critical, the Fuji is a good buy.     

Offline John Grossbohlin

Re: Trek 520
« Reply #25 on: March 04, 2017, 11:27:49 pm »
So I've gotten hooked reading about touring. I've a pretty avid hiker, and this appeals to me in so many ways. Well, my question is this...

I've been doing tons of research, and it seems that I'm leaning toward buying a Trek 520 for my first touring bike. I want to know why some of you think I "shouldn't" buy this bike. I keep reading great reviews, but I need the opinion of some vets to reassure me that I'm making the right decision.

Thanks in advance!
SPC
I bought a couple 520s, one for my son and one for myself. We rode them on the Erie Canalway route and through the Rockies from LaJunta, CO to Pasco, WA. In the Rockies we mostly used the TransAmerica and Lewis and Clark routes. The next year we needed another bike for my other son... unfortunately I didn't move fast enough that year and there were no 520s to be had and few LHTs. I ended up getting a slightly larger LHT for myself and put my son on my 520. We rode from FL to NY with them. 

Bottom line... it didn't really matter which bike I was on from a mechanical reliability, riding or comfort perspective... tires excepted. 

I put Brooks Flyer saddles on all of them from day one. Tires... In my opinion throw the stock tires away and put Schwalbe Marathon Plus on just before you start your trip. All of the Trek's Bontrager tires delaminated during the trip in the Rockies. I found a pair of 700x28 Schwalbe tires in Hamilton, MT and put them on my son's bike (at age 15 he was a lot lighter than I). The tires from his bike went on mine but they were completely shot by the time we were done... perhaps 2,000 miles on them. They were replaced by Schwalbe tires also. The Continentals on the LHT were showing cracks by the end of the trip... again about 2,000 miles. Plenty of flats with the OEM tires...

If the cosmetics are a deciding point I think the 520 probably wins. Otherwise... I don't see a practical difference.

My original touring bike back in the '80s was a Trek 850 (Trek's first mountain bike) that I set up for touring with road tires, racks, and extra bottle cages, Cannondale panniers, etc. There weren't too many "touring bike" options in those days (the Trek 520 and 620 being the notable exceptions) and I already had the 850 so that is what I went with. Other than the bars, from looking at photos of loaded bikes, I imagine my 850 touring rig wasn't much different from a LHT with 26" wheels. The photo shows the 850 the day after I finished the 3,142 mile '86 trip... the day I finished I rode from East Stoudsburg, PA north on Rte 209 in a light snow storm for about 80 miles and the last 35 on wet roads... everything was covered in grit including me. I look at it today and think that I was carrying way too much stuff! ::)
« Last Edit: March 04, 2017, 11:29:43 pm by John Grossbohlin »

Offline driftlessregion

Re: Trek 520
« Reply #26 on: March 12, 2017, 10:03:57 pm »
Read this from Adventure Cycling Magazine to learn about trail etc.
http://www.adventurecycling.org/default/assets/resources/20140601_MechanicalAdvantageTrail_Heine.pdf