Idler pulley

Radical Brad

Garage Hacker!
Staff member
Joined
Mar 13, 1999
Messages
5,425
Location
Kakabeka Falls, Ontario, Canada
Website
www.atomiczombie.com
Those idler sprockets would indeed work.
A few points of concern would be...

  • They are usually not available to fit bicycle chain (especially thinner shifter compatible chain).
  • They are probably not available in 4-6" diameter for bicycle chain.
You could try "machining" one down by attacking it with a flap disc if you can find at least the correct pitch.

Brad
 
Joined
Apr 15, 2013
Messages
1,702
Location
Washington state
This was discussed several times over the years and I believe it was determined that a sprocket actually brings to the tale more friction?
Thus reason for flat, non toothed idler pulley.
 
Joined
Nov 9, 2011
Messages
875
Location
Banglen, Thailand and a little bit Reading, UK
SJ - just knocked up a thin card template with the hole centres on it, then centre-punched them through on the plastic for drilling........mind you, the holes are just decorative, not really needed.

Mr I - not claiming to me a chainologist, but my understanding is chains are designed to run on their rollers, rather than side plates, so to me sprockets make sense for both drive and return runs. Also, getting them in the centre of the run, with the least amount of deflection, should me aimed for.
 

Twinkle

Super Moderator
Joined
Apr 14, 2013
Messages
3,474
Location
Peacehaven nr Brighton, Sussex ,UK
This was discussed several times over the years and I believe it was determined that a sprocket actually brings to the tale more friction?
Thus reason for flat, non toothed idler pulley.
After a few hundred miles my smooth pulley is no longer smooth

SJ - just knocked up a thin card template with the hole centres on it, then centre-punched them through on the plastic for drilling........mind you, the holes are just decorative, not really needed.

Mr I - not claiming to me a chainologist, but my understanding is chains are designed to run on their rollers, rather than side plates, so to me sprockets make sense for both drive and return runs. Also, getting them in the centre of the run, with the least amount of deflection, should me aimed for.
Nice job Frank my source of pulleys appear to have dried up , will try knocking up a couple next time .

regards emma
 
Top