Climbing Spooky Tooth?

[yoothgeye]

So we put my tall bike back together a couple nights ago. Cody really wanted to make it taller, he suggested a couple feel, I said 10", he said 12", I countered at 10.5", so he did. He chopped my steerer and removed my steer tube and lengthened it and tacked it altogether. Then we braced the rear and got it good and solid. The extra height really changed the chain routing, when it was shorter I could take out chain tension by adjusting the wheel in the dropout, but at the new angle that won't work.

So when we got the building buttoned up the other night we threw on some pedals and added some chain and once it was on there was alot of slop, instead of removing links (I was in a hurry, wanted to ride) I grabbed a chainring I had with a cut out center and put it in as a spooky tooth to tighten the chain. It works great!

Well, yesterday as I was riding, I got off and it looked like the spooky tooth had climbed the chain and the chain was REALLY tight. I didn't think this was possible. The spooky tooth is 42 teeth, is it possible that I need to use an odd number tooth? I got off the bike and backpedalled it (freewheel) really fast and after a few seconds the spooky tooth fell out! Oops. So when we went on a family ride for a few miles a little later I just didn't pedal backwards, haha.

So could it be climbing?

 

[deorman]

:?: Seems to me that since the same amount of chain passes off the drive sprocket as passes on, that wouldn't be possible. :?

 

[yoothgeye]

:?: Seems to me that since the same amount of chain passes off the drive sprocket as passes on, that wouldn't be possible. :?

I feel the same way, my chain has no way of counting teeth or knowing how many links long it is. haha I think what my be happening is I have not yet put a single speed freewheel on the wheel yet, so it is (I think) a 7 speed. When I built the bike originally I didn't have a single speed freewheel so I ground the teeth off of upper and lower sprockets so they wouldn't try to grab the chain and move it up or down. On this setup I am on a taller ring than before and it might be jumping up and down. All this should be fixed once I put on the SS and permanent upper chainring. I might try to get lucky with removing links, but the spooky tooth is neat to watch and gets people interested in the mechanics of it asking questions.