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View Full Version : Idler pulleys for chain.



stuartm9999
02-13-2011, 10:22 AM
Anyone recommend a good source of these for UK either online or shop in Belfast. I tried using some spare derailleur cogs but chain falls off the bottom one.
If you want to know how the voyageur build is going - on hold at the moment. I assembled the bike but then had welding, chain drive and arm problems!

More info on my blog (http://www.top-beer.co.uk/post/2011/02/13/Broken-mask-broken-welds-broken-parts-and-a-broken-arm-e28093-bike-retail-therapy-required.aspx).

Hope to get restarted soon!

Fathom
03-02-2011, 06:22 PM
you could try this http://www.expertfitnessuk.co.uk/pulley-wheels-188-c.asp, 7mm wide should be wide enough to take bicycle chain.

John Lewis
03-03-2011, 12:48 AM
I used one of those on my Wolf. The bearings suck and last about 3 weeks. I eventually fitted a proper ballrace. I had to cut a groove for a circlip to keep it in.

John

stormbird
03-03-2011, 02:12 AM
Hi there

Are these drive side idlers or return side ?

The drive side need to be stronger than dérailleur cogs , they will just disintegrate.

For the drive side they can be cut from the large wheels found on some kid's roller blades or those poor Chinese scooters popular a few years ago [ mount in a drill and file/cut a groove for the chain ] .

For the return side they can be made from dérailleur cogs , why not just add some large washers to turn the cog into a pulley ?

regards Paul

stuartm9999
03-03-2011, 04:26 AM
They are for the drive side.

Have a bid for these - http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260745138425&ssPageName=STRK:MEBIDX:IT - on ebay which I'm hoping a) I will win and b) will do the trick.
Look like the recomended part.

midmitrike
03-03-2011, 12:23 PM
Stuart,

For my Warrior build I struggled to find suitable idler pulleys. My local sources all wanted too much money for V-Belt pulleys with bearings. After a bit of searching here on the forum I found this post - http://forum.atomiczombie.com/showthread.php?3732-Can-t-find-quot-guide-pully-quot-(wheels)&p=36089#post36089.

The poly cutting boards were purchased at Walmart, small board $2.97, larger board $6.97. I had to purchase the necessary hole saws, but now I can build as many as I need. :D

Just run the hole saws thru the poly board and use light pressure so you don't build up too much heat and melt the plastic. After cutting out the discs I tightened a 1/4" bolt thru thru the pilot hole and chucked them into my drill press. I took a coarse file and gave the 2 outer discs a beveled edge and cleaned up all the remaining edges. Then I bolted 4 discs together and drilled 1/8" pilot holes thru to fasten them together. I only had 1" counter sunk screws so I had to put screws from both sides of the pulley. I will drill the center hole out as needed depending on how I finally decide to attach them.

I have yet to get them put on my Warrior build, but I am confident that they will work fine. Here are a few pics of how my pulleys turned out.
2058205920602061

John Lewis
03-04-2011, 01:35 AM
I have used two like this shown here on the Marauder.

A piece of black nylon rod (Lubron?). I cut a slice and turned and bored it on my home made lathe. it has a channel for the chain. There are two ballraces. In the centre is a circlip to stop the races moving when bolted up. Without the clip the pulley eventually slides adrift. It is on the power side.

http://i254.photobucket.com/albums/hh98/lew2au/Marauder-Build/tube2.jpg

I used roller skate wheels on the Bentech both power side and return. With the Wolf I needed a larger pulley hence the one from exercise eqipment. I intend to replace the Wolf's derailer return with a chain tube as you see above on the Marauder.

There are plenty of ways to create a pulley. Just use the imagination. Likewise if you need a simple lathe it is not too hard. I even used a pole lathe set up when doing the Wolf's hubs. You can see some of it in my Wolf thread.

John

keith9534
03-04-2011, 09:57 AM
I would think that metal v pulleys would be noisy and will wear the chain plates after a short time?.

John Lewis
03-04-2011, 08:53 PM
I would think that metal v pulleys would be noisy and will wear the chain plates after a short time?.

I'd agree. Some I've seen on a commercial bike had a rubber band over the pulley for the chain to run on. I think it was a seal from irrigation pipe by the look of it. I've also seen on other forums where people have cut bands of bike tube and stretched them over. Maybe six layers. Neoprene O rings are also used.

Except for the cost terracycle idlers are the go. I have a Greenspeed one on my LogoTrike. They sell at a reasonable pice but only have a single race.

John

Odd Man Out
03-04-2011, 10:48 PM
Terracycle has a large selection to suit the needs of those with deep pockets...

http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL

IrvJamison
03-05-2011, 12:55 AM
On the subject of pulleys, has anyone tried contacting Terracycle? No one answers either phone number and has not returned my calls (3) from a month ago!

Odd Man Out
03-05-2011, 02:14 AM
irv
Do you know that Terracycle is located in Portland off of S.E. 39th? You could drive over and talk to them -- they are really nice, helpful humanoids.

Trike Lover
03-05-2011, 10:17 AM
Looking at the TerraCycle site confirms a thought that's been lurking in the back of my head, but that as a newbie I wasn't sure I should bring up for fear of sounding like an *****.

Idler sprockets running on ball or roller bearings. This appears to be what Terracycle's power side idlers are (except the sprocket is set between two plates).

Princess Auto here in Canada make idler sprockets in a variety of sizes that run on ball races or Oilite bushings, and they're way cheaper than the Terracycle power-side sprockets. Also, it seems to me that it should be possible to take a small sprocket from, say, a kid's bike (sorry about that, son) and fit it with a ball bearing or bearings.

This needs some research, but there, I've said it, and I'll be some other AZ Krew member has already welded or shrunk-fit a small sprocket to a ball bearing race, or a pair of them, perhaps with a piece of tubing running through the middle to accept the bearings. If not, perhaps it can be done, and should be done.

Another thought: I wonder how well some of the hi-tech 2-part epoxies would work for setting a ball bearing race into a sprocket? My guess is that they would fatigue, but I'm often wrong, so perhaps someone has already done it?

Just some food for thought. Feel free to tell me why it can't be done. I'm betting that it can.

John Lewis
03-06-2011, 02:24 AM
There are some more guide pulley ideas here.
Using the bike sprocket and adding a ball bearing is interesting. I would also add some plastic side disks as a guide.

http://forum.atomiczombie.com/showthread.php?4203-Simple-guide-pulley-ideas

Permanent Loctite is good for some things. I tried it to hold bearing in a nylon pulley. No good. I tried it on a model engine flywheel. No good when it gets hot.

I'd be loath to trust it although metal to metal on n idler it might be fine.
John

Radical Brad
03-06-2011, 11:24 AM
There will be a bit of noise using an idler sprocket, but other than that they work very well.

Brad

Trike Lover
03-07-2011, 11:19 AM
John,
I had a feeling someone must have tried something like the kid's bike rear axle. Thanks for the link.

As to Loctite, I don't think it would stand up to the inevitable sideways flexing you'd get between the plate sprocket and the bearing.

I don't know about things like J-B Weld, but from past experience my guess is that it, or any epoxy, would also fail after a while for the same reason. I wish this were not the case, as it would be far simpler than trying to find a tube that would be a shrink-fit or press-fit for a bearing race, as well as being "fittable" into the bike sprocket. Ah well, that's what files are for......






There are some more guide pulley ideas here.
Using the bike sprocket and adding a ball bearing is interesting. I would also add some plastic side disks as a guide.

http://forum.atomiczombie.com/showthread.php?4203-Simple-guide-pulley-ideas

Permanent Loctite is good for some things. I tried it to hold bearing in a nylon pulley. No good. I tried it on a model engine flywheel. No good when it gets hot.

I'd be loath to trust it although metal to metal on n idler it might be fine.
John

Trike Lover
03-13-2011, 10:19 PM
I'm overcome with guilt. Tonight a little girl is minus her pink bike with training wheels and coaster brake hub. I feel soooooooooooooooooooooo guilty, LOL. Her mother insisted I take it away. Nice fork stem on it too......

John Lewis
03-14-2011, 06:18 AM
Oh you mean beast!:jester:

I hope she is lined up for a new bike.:scooter:

John

Trike Lover
03-15-2011, 11:45 PM
Yep.

As soon as the four feet of snow in the yard melts, her mum has a new bike waiting for her.

In the meantime, the rear wheel hub/sprocket is already on its way to becoming a power-side idler. As soon as the snow in my yard melts and its warm enough, I will be able to start welding up my DW frame. That should be about......June. I live a long way north of Kat and Brad, and the building season here is even shorter.

BTW, John, I very much enjoyed seeing pictures of your Dave Gingery lathe and shaper. I bought the whole series of books when they first came out, but have yet to build any of the machines. Now I'm well into preparations for building my Delta Wolf, they will have to wait a while longer. I wonder if the indexing attachment could be set up for drilling spoke holes....hmmmmm......a paper template is probably a simpler way to do that.

Jim

John Lewis
03-16-2011, 07:40 AM
Brrrr! Jim,

I don't know how I'd go up there. I hate the cold.

My Gingery lathe has done lots of work. The shaper not so much. I am still wnting to make the mill.
I think the 1/4" he uses for ways on the machines is too light. I used 3/8" on the shaper and it is much better.
Here's an easy way to make an indexer that I use for doing clock gears and all sorts. Not made one for indexing hubs yet but have thought about it.

In essence you take a piece of bandsaw blade that has a multiple (+ a few) of the number you want teeth and glue/pin it round a wooden disk.
I usually fit a hub with a setscrew and it gets stuck on the end of the lathe shaft. Or sometimes on a shaft sitting on the drill press.
I have a piece of springy metal clamped to act as a detent and thats it. It is very accurate or at least so for making most simple gears.

I thought of making one special to go under the drill press to do hubs. Next time I make a bike that needs it I'll give it a try.
I'll upload a picture to make it all clear later if I can find some.
John