John Tolhurst
Zen MBB Master
Silvio Mule, or prototype II, I see no entry in the brag board, so here we go.
First built in April 07, the upper section of the boom is carbon fiber. I deleted this for production and went back to alloy to maintain better stiffness. I have bolted every variation I could think of up on this frame, racks, rear tailbox, it has had four lower boom sections and it still has a handmade cup that goes under the handlebar attachment clamps. It has had I think 3 different road bars, now has the origin-8. It has even had tri bars on it, arranged to sit under a fairing.
Ever since it was first built the chain has been so long that even on the big ring and large sproket, the deraileur was taking up slack, and the added length of the chain return line allowed me to run that combo ok. So I would often ride just on the big ring and using most of the 12-27 cluster. It has 170 cranks that are probably 10 mm too long for me.
Because of the long chain, running in the small at the front was mostly terrible except for the two big sprockets. How can someone live with that I hear you ask. Ah well, there is always something more interesting to do in the shed than resizing the chain. Anyway it has all caught up with me. The slack chain eventually entered the rear derailleur cage the wrong way and jambed, I freed it by kicking the pedal very hard while riding. This bent the cage and twisted the chain - but at least I didn't have to stop and get dirty hands!!!!! So a rebuild was in order and, finally, yesterday it got done. I removed 4" from the chain!! Now it won't run the big-big combo since its only a short distance from the big ring to the RD cage and the entry angle into the cage causes the chain to rub on it. But on the other hand, I can now run all the gears as I'm supposed to. I also had to remove one side of the cage and straighten each side. This was difficult as it was hard to pick where it should be. Then I bolted it back up and bent it again by hand with the outer end of the cage clamped in the bench vice. On the stand, and looping the driveway it ran all the gears very nicely.
Pictured on the Silvio prouduct page thus:
First built in April 07, the upper section of the boom is carbon fiber. I deleted this for production and went back to alloy to maintain better stiffness. I have bolted every variation I could think of up on this frame, racks, rear tailbox, it has had four lower boom sections and it still has a handmade cup that goes under the handlebar attachment clamps. It has had I think 3 different road bars, now has the origin-8. It has even had tri bars on it, arranged to sit under a fairing.
Ever since it was first built the chain has been so long that even on the big ring and large sproket, the deraileur was taking up slack, and the added length of the chain return line allowed me to run that combo ok. So I would often ride just on the big ring and using most of the 12-27 cluster. It has 170 cranks that are probably 10 mm too long for me.
Because of the long chain, running in the small at the front was mostly terrible except for the two big sprockets. How can someone live with that I hear you ask. Ah well, there is always something more interesting to do in the shed than resizing the chain. Anyway it has all caught up with me. The slack chain eventually entered the rear derailleur cage the wrong way and jambed, I freed it by kicking the pedal very hard while riding. This bent the cage and twisted the chain - but at least I didn't have to stop and get dirty hands!!!!! So a rebuild was in order and, finally, yesterday it got done. I removed 4" from the chain!! Now it won't run the big-big combo since its only a short distance from the big ring to the RD cage and the entry angle into the cage causes the chain to rub on it. But on the other hand, I can now run all the gears as I'm supposed to. I also had to remove one side of the cage and straighten each side. This was difficult as it was hard to pick where it should be. Then I bolted it back up and bent it again by hand with the outer end of the cage clamped in the bench vice. On the stand, and looping the driveway it ran all the gears very nicely.
Pictured on the Silvio prouduct page thus:
