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On my shifter above, the wrench fit the splined piece that turns pretty well. No slipping just a bit of play. So I cut the splined part to the approximate thickness of the wrench head and loaded it up with JB Weld to take up the play. The handlebar bit it fit on was welded to the frame and I drilled a hole inside, through the frame for a piece of threaded rod. The threaded rod holds a smaller washer the size of the splined part and a larger chrome washer bigger than the wrench head. Topping it all off with chrome acorn nuts on both ends of the threaded rod. Savvy?

Sent from the edge of an alternate universe...
 
One- The plastic ring I made the collar out of is too soft.

Two- PVC is very brittle when you grind it very thin.

Three- It only takes 2 seconds to waste an hour of work!
How about the bell part from a bike bell?
images (1).jpg
 
DAng, and that PVC cover looked pretty good too.
 
@Psychographic I work in steel when i can with nothing more than handtools. A decent hardware store should have large washers to make your collar from. With your outside dimension the same you'd probably have to round file out the inside, with your inside dimension the same you could grind down the outside on a bench grinder (or hand grinder) drill some holes and tap some threads. I don't know if you need to there, but handy stuff to be able to do when modding. I like @toro1978 's idea with the bell cover too.
It's early in the buildoff, we've got plenty of time...

Carl.
 
My sprockets finally showed up today. I threw them on the adapter, put the back chain on, it dropped right on. Then tried to put the front chain on and the sprocket is too fat. I must have grabbed a 3/32 chain, let me get one I know is 1/8. NOPE! I have a very limited supply of parts, and the only chain that fits is the green one I bought for my other build.

Is there a third size chain I'm unfamiliar with?
 
Single speed chain? Those, besides the 1" pitch skip tooth are the only ones I've used. I wonder if it's your front chain ring that is the issue. Maybe designed for a specific application?
 
Single speed chain? Those, besides the 1" pitch skip tooth are the only ones I've used. I wonder if it's your front chain ring that is the issue. Maybe designed for a specific application?

I'm not 100% sure the chain that fits is the original chain. I only have one 20" single speed bike that I could have taken a chain from. I'm guessing that would be too short to fit this 6 speed.

The problem is definitely the width of the idler sprockets which are single speed sprockets the screw onto a hub without using a freewheel. The outer links of the chain fit perfect, the inner ones are just a touch too narrow.

Are single speed chains a hair wider?
 
Yup single speed chain is wider, I usually identify my chain by wrapping it around the sprocket. A single speed chain will start not fitting about halfway around a multi speed sprocket and pop and hop if you try to ride with it like that
 
Yup single speed chain is wider, I usually identify my chain by wrapping it around the sprocket. A single speed chain will start not fitting about halfway around a multi speed sprocket and pop and hop if you try to ride with it like that

I sure have a lot to learn!

So I'm guessing the chain on the back of the bike will need to be swapped out, this brings my next question.

As it seems I have a single speed chain on a 6 speed freewheel, I will need to shave down the width of the idler sprocket that goes to the rear wheel. The sprockets are mounted to the BB, I could hook the opposite side to a drill and while it's spinning, grind the one sprocket slightly to fit the multi speed chain.

Can I get away with shaving just one side of the sprocket?
 
I had to go back to page 2 to find a pic of the idler.
I'm wondering if you can swap a cog on the idler?
It doesn't have to just bend your chain line,
it can swap chain types too.

Carl.
 
I looked back just now, and couldn't find a photo of the actual idler sprocket. If you could do a close up shot of this, it might be easier to determine how much or if grinding the sprocket teeth will help the situation.

As dropstep said, the single speed chain is wider than the multi-speed; and multi-speed chains vary as well. Make sure you have a 6-8 speed chain on there for your set up in the rear. A 9, 10, or 11 speed chain will not work.

Again, a close up shot would be helpful.

On the ++ side, Psycho, you definitely have the 'spirit' of this down pat. Sharing your process and asking for ideas / input is what this is all about! RaT oN~!:thumbsup:
 
I don't know much about bikes, but I'm assuming there are no single sprockets made for a multi sprocket chain.

I'd like to know who came up with some of the measurements for bikes. A 20" wheel measure 16" unless it's a 451, then it's larger, but it's still considered 20". Now I see a 1/8" chain can have two widths.
 
As dropstep said, the single speed chain is wider than the multi-speed; and multi-speed chains vary as well. Make sure you have a 6-8 speed chain on there for your set up in the rear. A 9, 10, or 11 speed chain will not work.
When you say 9, 10, or 11, does that count just the rear sprockets or total of front and rear?
 
When you say 9, 10, or 11, does that count just the rear sprockets or total of front and rear?
Just the rear cassette. In modern geared bike speech, we refer to a 10 speed bike as one that has a cassette with 10 cogs. In the '70s, we referred to a 10 speed bike as one with two chain rings in front, and 5 cogs in the back.

The chain you want is one for an 8 speed bike. It fits 5 - 8 speed rear freewheels or cassettes.

I like the SRAM PC850. The SRAM master links are easy to use, and allow you to get the proper length of the chain.

You will need to 'break' the chain, it will come too long (likely) for your configuration. If you really get into this hobby, you will want a good chain tool.
 
Here's a photo of the SRAM chain I was talking about.
sram pc850.jpg


And the chain tool I like to use, for 31 yrs now... the Park Tool CT-5 mini chain brute. Works great for single speed - 8 speed applications.

parktool ct-5 mini chain brute.jpg
 
I don't know much about bikes, but I'm assuming there are no single sprockets made for a multi sprocket chain.

I'd like to know who came up with some of the measurements for bikes. A 20" wheel measure 16" unless it's a 451, then it's larger, but it's still considered 20". Now I see a 1/8" chain can have two widths.

There are single sprockets made for multi speed chains, but I'm not aware of one that would be smaller than around 20t (teeth). It would be what we used to call the 'granny gear' (smallest chain ring) on a triple chain ring mountain bike set up.
 
Thanks for all the information and help, I really appreciate it! I know how frustrating it can be dealing with a noob. My experience with bikes goes back to the 70's at the latest, and as a kid, who cared how things worked as long as they looked cool.
 
Some pics of the sprockets.

PA160582.JPG
PA160583.jpg
PA160584.jpg
PA160585.jpg





This is my idea on slimming down one of the sprockets. Spin it with the drill and then just kissing the lower end of the taper of the teeth with the grinder, or possibly a dremel. I'm thinking the 4.5" grinder would be less prone to bouncing around due to the larger diameter disc. Heck, I might even be able to use a file on it.

PA160586.jpg


Good idea or bad?
 
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Can you get a replacement cog after you (Oops!) trash this one? and as always, your results may vary...

Personally I'd lean towards replacing the odd gear that doesn't match the rest of them. But I have heard of guys thinning down sprockets before. Take your time, check and recheck repeatedly, you don't want to take off too much.

Carl.
 

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