to rag or not to rag

[johnsteve]

So i have been thinking about building a new bike and I am not sure whether or not to use the rag mount to the sprocket. I have heard that they are usually hard to true and problems with the chain falling off.

Anybody ever have these problems in the past? Should I just go ahead and buy another hub or sprocket attachment? If so what should I use?

Thanks in advance

 

[butterbean]

The rag joints are "OK". Not really that hard to true unless the sprocket is warped to begin with, which does happen from time to time. The main issue is that it does put more pressure on the spokes. You can go with a sprocket adapter, they usually work pretty well. As long as you buy the right one to fit your hub and tighten it down properly, it will work fine. The other option is to go with a moped hub, the sprocket bolts directly to the hub so no rag joint or adapter is necessary. You will have to lace and true the wheel yourself, and also most likely will need to spread your dropouts. But they come with a drum brake and are also threaded for a freewheel.

 

[crassius]

I always use the rag joint - takes a bit of practice tho.

I have never used an adapter since most only fit coaster brake wheels & I refuse to build on something that unsafe.

 

[springfieldscooter]

To me, the main advantage of the hub adapter is to transfer torque to the HUB, instead of the SPOKES.

If your using a low horsepower engine, with heavy duty 12 gauge spokes it shouldn't really matter.

Now if your using a department store rim with the rag-joint, youll be o.k. for a few hundred miles, then look out!

 

[butre]

To me, the main advantage of the hub adapter is to transfer torque to the HUB, instead of the SPOKES.

If your using a low horsepower engine, with heavy duty 12 gauge spokes it shouldn't really matter.

Now if your using a department store rim with the rag-joint, youll be o.k. for a few hundred miles, then look out!

few hundred meters maybe

 

[HeadSmess]

To me, the main advantage of the hub adapter is to transfer torque to the HUB, instead of the SPOKES.

dont you want the torque transmitted to the RIM?

like, iunno...but isnt the tyre attached to the rim and thats the bit that gets you moving?

and so...any load driven into the hub...still has to go through the spokes to the rim?

iunno though....

pffft, rag joints work, they maynt look high class, they may take some fiddling to get on nice and straight, but they work...and dont require relacing or buying a special wheel or anything like that...just pop em on...


stuck em on flimsy 27inch racer wheels with no troubles... until the frame snapped!

 

[butre]

the big advantage with hub adapters is that it makes the wheel easier to true. the way I ride that's a huge advantage

 

[johnsteve]

so it just takes practice to get it right on a twelve gauge spoked wheel. Makes sense. It was a major PITA to get it right for me the first time and trying to figure out why my chain kept falling off. I am thinking was it the sprocket or was it the tensioner. It also did not help that i tightened it uneven to begin with. Thanks for everyones comments.

They help,,,,,,,,really.

 

[KCvale]

Actually the rag joint system is better than a clam shell to me.

It puts a slight buffer between the engine and drive wheel.
Not much, like .2mm 'give' but something for those hard clutch drops and 9 bolts holding it.

If a clam shell gives it's 3 or 4 bolts spin on the hub and take out spokes.

The thing is, they are just not that hard to install.

1. Put your sprocket on a flat surface and makes sure it's true.
You can never true a warped sprocket and I have probably 15 new ones that were warped right out of the box in my sprocket pile.

2. Get the sprocket bolted in kind of loose, flip your bike over and put the wheel on (or put in a fork in a vice like we do), so you can spin it.

3. There are 2 things to look at...
Side to side wobble, look at it edgewise for this.
And up-down no-center issues, look at the sprocket face for this.

Side to side will throw chain, up and down will cause the chain to get loose, then tight, then loose again.

Adjust your 9 bolts in a star pattern and look as you go.
It also helps to see how much bolt end sticks out on the inside after the nuts are on, keep them close as you go.

Finally, if you get it true horizontal wobble wise but have an issue with vertical up and down, you can put a piece of junk chain in the sprocket and tap it down into place vertically on that.

4. Which way to cup the sprocket.
This depends entirely on where your engine output sprocket is.
The back sprocket has to be in line with it.
415 chain don't bend around fat tires with a sprocket cupped wrong and a tensioner not centered in the true chain line .
That goes for any mount system.

I have ~60 builds with rag sprocket drive and just don't have problems.

Just a side note, they are not rags, those rings are punched out of used tire sidewalls.
That means they are not all the same and they have a slight curve to them.
Done properly and tight they give enough for the spokes and come together to grip as one piece.

 

[butre]

Actually the rag joint system is better than a clam shell to me.

It puts a slight buffer between the engine and drive wheel.
Not much, like .2mm 'give' but something for those hard clutch drops and 9 bolts holding it.

If a clam shell gives it's 3 or 4 bolts spin on the hub and take out spokes.

The thing is, they are just not that hard to install.

1. Put your sprocket on a flat surface and makes sure it's true.
You can never true a warped sprocket and I have probably 15 new ones that were warped right out of the box in my sprocket pile.

2. Get the sprocket bolted in kind of loose, flip your bike over and put the wheel on (or put in a fork in a vice like we do), so you can spin it.

3. There are 2 things to look at...
Side to side wobble, look at it edgewise for this.
And up-down no-center issues, look at the sprocket face for this.

Side to side will throw chain, up and down will cause the chain to get loose, then tight, then loose again.

Adjust your 9 bolts in a star pattern and look as you go.
It also helps to see how much bolt end sticks out on the inside after the nuts are on, keep them close as you go.

Finally, if you get it true horizontal wobble wise but have an issue with vertical up and down, you can put a piece of junk chain in the sprocket and tap it down into place vertically on that.

4. Which way to cup the sprocket.
This depends entirely on where your engine output sprocket is.
The back sprocket has to be in line with it.
415 chain don't bend around fat tires with a sprocket cupped wrong and a tensioner not centered in the true chain line .
That goes for any mount system.

I have ~60 builds with rag sprocket drive and just don't have problems.

Just a side note, they are not rags, those rings are punched out of used tire sidewalls.
That means they are not all the same and they have a slight curve to them.
Done properly and tight they give enough for the spokes and come together to grip as one piece.

a properly installed clamshell that's been machined to spec will not slip one bit.