bikerumor monday mystery pic submitted by University Bicycles in Boulder, Colorado,

Photo submitted by Andy Wiedrich, Warranty Manager at University Bicycles in Boulder, CO,


  1. Whats so mysterious about about this?!? Weren’t you guys around when this “early version of Shadow+” was out?
    They bent terribly easy!! 🙂

  2. Bullet Bros. Chain tensioner. I used one successfully on my Fat Chance dual slalom bike back in the mid 90’s. It was the only thing on the bike not anodized turquoise! Goes great with grip shift and grunge music over the PA system.

  3. Bullet Brothers chain tensioner….94 or 95…I had one…and didn’t they buy a helicopter with the money that made off this stuff?

    @Evolvo13….only goes good with the Gripshift if you also have a bassworm or replaced the spring in the Shimano rear derailleur so it worked with the SRT-800 Gripshift…stupid Shimano.

  4. Wow. That was something I came up with in 94. I even had a two piece one that was shorter. It would have been nice if they gave me some cash for taking my idea.

  5. I don’t see anything weird other than a badly-kinked piece of cable housing. (And my tandem still has a bassworm – makes avid disc brakes work a LOT better with the long cable)

  6. @nurse_pete – I’ve been keeping a couple of bassworms in my spare parts box for a LONG time to take care of bad cable routing or poor return-spring tension. They’re great. I’ve got some spare tubing to use when they eventually die, too.

  7. It was part of the Tyson system with a couple of rollers around a single chainring. Of course, when the license ran out it was simply called the Mr Dream system.

  8. Andy, I think Hossaflook still has one of these hanging in his garage. It was a great idea, think about it, all new rear derailleurs have have a “locking” mechanism in them now to prevent chain-slap.

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