Necessity is the mother of all invention and being broke only heightens the situation.
Buying guide pulleys for chain runs is a prime example of the above creed as they can be very expensive.
In true Atomic Zombie fashion, I have come up with one or two ideas that I wish to share using scrap bike bits and other scrounged parts.
The easiest fix to the problem is the get hold of a child’s single speed free wheel found on the back wheel of toddler type bikes.
Remove from the donor wheel and carefully trap it in a vice and with a hammer and pin punch unscrew the left hand thread face plate.
Watch out here as there are tons of tiny ball bearings in tracks on either side of the cog, an old towel draped between the vice jaws and under the freewheel will trap any wayward bearings.
When inside, simply remove the two pawls and their springs, clean up the ball races and the ball bearings, grease and re assemble.
You know have a freewheeling idler pulley with attitude that can be welded directly to your bike frame in way of the chain run.
A small metal tab welded to the back face of your new pulley body can be bent over but clear of the chain to prevent it jumping off. Look carefully at the photo below and you can see my anti chain jumping tab towards the bottom of my attitude idler!
If you plan to weld your new pulley to your bike frame it’s a good idea to fix the idler body to your frame first to avoid grease meltdown during welding. When everything is cool again, fit greased ball races, cog and face plate and we're done!
Here's one I prepared earlier accompanied by an old roller skate wheel for the return path to the chain rings at the pedals.
A bolt passing through the frame has a spacer in way of the toothed idler pulley preventing the skate wheel pulley from binding, or if you're brave a stud bolt may be welded inside the centre of your toothed idler which gives a neater appearance.
A larger diameter toothed idler pulley can be made using the largest cog from a dismembered 5 speed freewheel plus two tiny ball races taken from the ends of a carpet beating brush spindle borrowed from a discarded upright vacuum cleaner plus a small section of steel pipe and some scrap metal pieces.
I knew it was a good idea to take stuff to bits before trashing them when I was a kid! You find all sorts of interesting stuff inside plus tons of free screws, nuts and bolts etc!
Watch the space for an update of the larger attitude idler with photos soon. ~ GreggyB, AZ Krew Member