My fix for chain tensioneer

Discussion in 'Frame Mounted Engines' started by lucas, May 12, 2010.

  1. lucas

    lucas Member

    So i was tired of chewing thru those cheep plastic kit wheels.

    I dissasembled the rear derailer from a parts bike. threaded the rivited fixed bolt tha hold the derailer together to 3/8. put two nuts on the end to make sure it won't move. i have ridin alomst 200 miles with this fix and havent had an issuse yet. hope this helps.

    Attached Files:

  2. srdavo

    srdavo Active Member

    nice mod.... I like it!!
  3. lucas

    lucas Member

    Thanks. addss little bit noise as the chain rides over. I live in RI and we have potholes that will swallow your bike. the smaller ones just like to bounce your chain off the sprocket. it also eliminated any side to side movement of the chain.
  4. Dilly Bar Rob

    Dilly Bar Rob Member

    Good work!

    I have done something similar, but on the pedal side chain of a single speed, had some doubts of how much stress the derailleur wheels can take (a concern while starting the bike as the slac side turns into the tension side).

    Do you have a spring in there or is it "hard" mounted?
  5. lucas

    lucas Member

    Its hard mounted. i set it for a slight bit of play. but not enogh so that the chain could clear the sprocket. the sprockets are metal not the plastic ones. i aslo have this rig installed on my kits that has a 415 chain. sprockets still ride. i just had to grind down the side walls of the derailer to make the chain flow thru un touched.
  6. plinko

    plinko Banned

    You just solved my problem.Thank you
  7. darwin

    darwin Well-Known Member

    Just think of using a derailleur with the chain threaded through it and using the up/down spring function to tighten the chain.
  8. jared8783

    jared8783 Member

    Looks like a good idea and all bu i would imagine that using a bicycle sprocket for 415 chain would eventually cause some sort of problem like maybe wearing your chain faster or something.

    is the roller spacing the same on a 415 as a bike chain?