chain idlers



here ya go darren
i cut the tube out of a cheap metal chair leg so it already had the bends
check the angle of your cuts by putting the tube in position on the bike
i made 2 c shaped clamps out of 2mm plate and welded them to the ends of the pipe.
i made the sloted plate out of 4mm steel i sat the pipe/clamp assembly
on the bike marked out were to put the plate took it of tacked the plate in
position put it back on the bike i put an adjustabe wrench on the plate and
got it running square with the chain side to side and up and down took it
off and welded the the plate on painted it black droped it on the floor
painted it black again and put it on the bike :cool:
if you have a close look you can see the top clamp is level with the top of the chain it was too close and i had to shift the rear wheel over about 2mm
something to think about when you looking where to put your clamps just about anywere except were i put the top one on mine:eek:
the other chain idler i made from an old rear deraileur and i made the mount
using the hand press at work (i work in a press shop)
i like it becuase i don't have to worry about chain tension all the time but i don't think the spring will last too long its done about 400kms and the arms not as tight as it was but no problems with bending the deraileur is made of stainless steel
i used the round nut off a bike tube on the bolt holding the cog
it fitted onto the original cog bolt on the deraileur (i love it when a plan comes together) :eek:


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i tried a spring-loaded tensioner on my stretch MB...the slack was allowing for too much vibration of a new kind...went to a solid version, problem solved.

very nice post and some great innovation, thanks.

yea spring loaded aint perfect the spring is dying in this one but the effects are probably worse on a stretched bike or if the rear sprocket is'nt running true check this out
the only place i've seen them for sale so far
i ground the corners off the sprocket on the engine as it said to do in the manual it still felt (jumpy?) so i ground a bit more off and it made it a bit smoother would of been interesting to have tried it befor any grinding (has anyone)
i'm also thinking of grinding a lead in angle on the inside half of the narrow links in the chain (like on a bike chain) but that will have to wait till i'm in the mood for all those links:rolleyes:
if it makes it worse i'll just turn it inside out so it should'nt destroy a chain to find out. do you know if anyone has tried this?
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another one

i thought of this idea the other day a bit simpler and cleaner looking
only 2 pieces and 1 weld might make one when my spring tension chain idler dies i'll put pics up if i do till then hope this drawing makes sense


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Hey Rod-

Thanks for the pics. would you be able to get us a pic of the other side of your chain idler on the black bike? Much apreciated. I am curious how you attached the sucker. Thanks again.

more pics

hope this shows what ya wanna see darren i put the large fin on the top clamp to go behind the chain guard but it will have to wait till i take the wheel off to get the chain guard on the other side of it


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