Advertise on Bikeforums.net



User Tag List

Results 1 to 12 of 12
  1. #1
    Junior Member
    Join Date
    Jul 2014
    Location
    Belgium, Europe
    My Bikes
    Koga signature, Trek T 50, Challenge Hurricane
    Posts
    13
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Gates belt for Trek T50

    I have a tandem bike TREK T50 and I would like to install a gates belt to replace my timing chain. The distance between the front and the rear BB (heart to heart) is 700 mm. The bike has the original eccentric (wedge type).

    Is there a fitting belt and sprockets to fit this? I can not find it on the drive calculator.

  2. #2
    Senior Member
    Join Date
    Mar 2010
    Location
    City of Brotherly Love
    My Bikes
    Raleigh Companion, Nashbar Touring, Novara DiVano, Trek FX 7.1, Giant Upland
    Posts
    1,479
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Not sure if the T50 is stiff enough for a belt but the 74 tooth chainrings should fit at 704mm. The drive calculator isn't for timing belts.

  3. #3
    Junior Member
    Join Date
    Jul 2014
    Location
    Belgium, Europe
    My Bikes
    Koga signature, Trek T 50, Challenge Hurricane
    Posts
    13
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I asked Gates if the timing belt and 74T sprockets will do for my Trek with 700 mm between the brackets and they said yes. However, I read that the belt is on the right tension at 706 mm. I measured only 703 or704 mm with my eccenter to the max. Will this 2 mm difference make a difference between ok and no good?

  4. #4
    Nigel nfmisso's Avatar
    Join Date
    Mar 2011
    Location
    San Jose, CA
    My Bikes
    1980s and 1990s steel: CyclePro, GT, Nishiki, Schwinn, SR, Trek........
    Posts
    1,838
    Mentioned
    7 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Bezalel View Post
    Not sure if the T50 is stiff enough for a belt .......
    The T50/T100/T200 are extremely stiff, plenty for a belt.
    Nigel
    Mechanical Design Engineer

  5. #5
    Nigel nfmisso's Avatar
    Join Date
    Mar 2011
    Location
    San Jose, CA
    My Bikes
    1980s and 1990s steel: CyclePro, GT, Nishiki, Schwinn, SR, Trek........
    Posts
    1,838
    Mentioned
    7 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by bartel.michiels View Post
    I asked Gates if the timing belt and 74T sprockets will do for my Trek with 700 mm between the brackets and they said yes. However, I read that the belt is on the right tension at 706 mm. I measured only 703 or704 mm with my eccenter to the max. Will this 2 mm difference make a difference between ok and no good?
    Should be okay.

    We also have a T50. Frankly, I am amazed that someone would want to install a timing belt system that costs more than the whole bike is worth. In the USA, the T50/T100/T200 (same frame slight variation in components) go for $400-$700. I have done a number of upgrades to ours including: 40H Velocity Dyad rims on cartridge bearing hubs, 9 speed conversion (SRAM X.9 RD, 11-34T cassette, X.0 shifter), fenders and other minor things. We got ours used, and it came with 28-44-54 chain rings; now has a 26T granny. Some think that I am crazy for investing that much in the T50.

    Trek's first tandems (T50/T100/T200) are nice riding and very rigid. They are made of TIG welded True Temper butted Cro-Mo tubing, and have a large ovalized boom tube. They are not particularly light; but make up for that with very efficient delivery of power to the ground. It is very stable at high speed.
    Nigel
    Mechanical Design Engineer

  6. #6
    Junior Member
    Join Date
    Jul 2014
    Location
    Belgium, Europe
    My Bikes
    Koga signature, Trek T 50, Challenge Hurricane
    Posts
    13
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    In Belgium it's rather rare to find a Trek tandem and the price is between 800 $ and 1.000 $. Other second hand quality tandems are much more expensive and hard to find. Belgium is a small bike market with more conventional bikes or pure race bikes.

    To me a good frame (and I think the Trek has a good frame) is half the bike and I prefer steel frames. I only kept the frame and I replaced most of the components with pieces I already had in my garage.


    As there were some cracks in the rear wheel I bought new 48 spokes wheels with cartridge hubs. So now I have a good tandem for apr. 1.100 $. I will not find a second hand tandem with the same components and a good stiff frame. The only minor points are that the frame and fork are not adapted for disc brakes, the weight is rather on the heavy side and that it is not possible to retrofit s & s couplings due to the oval tube (or they have to replace the oval tube by a round one, what I do not want to do).

    As I have to lift the tandem often on and off the roof of my car I thought it would be much easier (and cleaner) If I had a belt instead of a chain. The price of two sprockets and a belt is apr. 240 euro what is a third of the price I paid for the bike and wheels.

    And most important, I like it very much to ride this bike.

  7. #7
    Nigel nfmisso's Avatar
    Join Date
    Mar 2011
    Location
    San Jose, CA
    My Bikes
    1980s and 1990s steel: CyclePro, GT, Nishiki, Schwinn, SR, Trek........
    Posts
    1,838
    Mentioned
    7 Post(s)
    Tagged
    0 Thread(s)
    A very good reason for changing to a belt. Go for it.

    Finding another tandem frame that is both stiff and nice riding is at a reasonable price is very difficult. Bill McCready of Santana has good things to say about the 1st generation Trek tandems

    I concur regarding steel; all of my bikes are steel, one is double butted Reynolds 531, one is hi-ten (low carbon) steel, and the balance are cro-mo alloy steel. I build or rebuild my bikes from the frame up, and I build my own wheels. Bicycle are a black hole hobby, not a business for me.

    Swapping the fork for a disc brake compatible one should not be a big deal - if your really want disc brakes. We have Avid SD5 linear pull brakes, which we find more than sufficient - we ride very few hills, and tend to keep it under 30kph, but we are a 500+lbs team.
    Nigel
    Mechanical Design Engineer

  8. #8
    Newbie
    Join Date
    Aug 2015
    Posts
    3
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    trek tandem

    Quote Originally Posted by bartel.michiels View Post
    I have a tandem bike TREK T50 and I would like to install a gates belt to replace my timing chain. The distance between the front and the rear BB (heart to heart) is 700 mm. The bike has the original eccentric (wedge type).

    Is there a fitting belt and sprockets to fit this? I can not find it on the drive calculator.
    hoi Bartel,

    is het gelukt om Gates riem op Uw tandem te maken.

    groet
    René

  9. #9
    pan y agua merlinextraligh's Avatar
    Join Date
    Aug 2005
    Location
    Jacksonville
    My Bikes
    Wilier Zero 7; Merlin Extralight; Co-Motion Robusta; Schwinn Paramount; Motobecane Phantom Cross; Cervelo P2; Motebecane Ti Fly 29er; Calfee Dragonfly Tandem
    Posts
    29,016
    Mentioned
    25 Post(s)
    Tagged
    0 Thread(s)
    is their an alignment issue. When belts first came out, Co-Motion did not recommend retrofitting bikes that weren't built for belts.

    Their point was the precision needed to align the two bb's for a belt was higher than for a timing chain, and they therefore only recommended belts for frame intended originally for belts.

    So my questions would be whether the alignment on a lower end frame is precise enough to avoid issues?
    You could fall off a cliff and die.
    You could get lost and die.
    You could hit a tree and die.
    OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.

  10. #10
    Senior Member
    Join Date
    Mar 2008
    My Bikes
    Giant TCR, Santana Team Scandium, Co-Motion Equator, Giant NRS Carbon
    Posts
    196
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by merlinextraligh View Post
    is their an alignment issue. When belts first came out, Co-Motion did not recommend retrofitting bikes that weren't built for belts.

    Their point was the precision needed to align the two bb's for a belt was higher than for a timing chain, and they therefore only recommended belts for frame intended originally for belts.

    So my questions would be whether the alignment on a lower end frame is precise enough to avoid issues?
    Purchased a Co-Motion Equator with belt drive on both the timing and drive. A couple things have changed since the belts were first released that I think makes putting a belt on a bike not designed with a belt in mind more acceptable.

    1. I'm not sure about this. Someone correct me if I'm wrong, but I think more ring sizes are available now, which allows the belt to fit properly on a wider variety of bikes that have different distances between the two bottom brackets. I remember being told that a belt would probably not work on the Santana I own, however recent research has shown that there's a set of rings that should work with the bike. There is still only one timing belt size.

    2. The newer belt design, (center-track), has a grove in the center. The older design has a lip on one side. Even with perfectly aligned rings, not having the right belt tension can lead to the belt creeping off to the side without the lip. If the rings are not perfectly in alignment, you're never going to keep the belt from sliding off one of the rings. The newer system shouldn't have this problem. Most tandems I have seen though (worked in shop for years and was knows as the "tandem guy") have their rings lined fairly close. The bikes I have seen where this is not the case usually is the result of running two different crank models to get a more desirable crank length for the stoker. My Santana was built before belts became an option, however both bottom brackets/cranks are the same spacing on the left. Again, the center-track system seems to deal with this alignment issue.
    http://www.technicallytom.com

  11. #11
    Junior Member
    Join Date
    Jul 2014
    Location
    Belgium, Europe
    My Bikes
    Koga signature, Trek T 50, Challenge Hurricane
    Posts
    13
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    René,

    I didn't install the gates belt because neither Gates in the U.S. or Germany were sure it would fit on my tandem.

  12. #12
    Senior Member
    Join Date
    Mar 2010
    Location
    City of Brotherly Love
    My Bikes
    Raleigh Companion, Nashbar Touring, Novara DiVano, Trek FX 7.1, Giant Upland
    Posts
    1,479
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    There's something wrong with your measurements. The eccentric has at least 1/2" (12.7mm) of adjustment so center to longest will be at least 6.35mm.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •