Sprocket Adapter by Sportscarpat

[sportscarpat]

Here is a new product I have been developing. It is a sprocket adapter with a few new features. The adapter assembly is of a three piece design. This makes it very easy to install through the spokes and because each of the three clamping parts are identical it is a balanced design.


DSC06064 by Sportsman Flyer, on Flickr

DSC06066 by Sportsman Flyer, on Flickr

Here is the assembled part mounted to a Worksman coaster brake wheel. Notice there are no clearence issues with the bolt heads and the coaster brake arm. Brake arm is unmodified.


DSC06067 by Sportsman Flyer, on Flickr

Here is another picture of the installed part.


DSC06069 by Sportsman Flyer, on Flickr

Please offer any suggestions or comments you may have as this is a prototype unit and I have time to make changes or modify the design. One thing I will probably change is the width of the clamping area. Since the three parts are so small they easily install through even 12 gauge spokes so making the clamping surface wider will not be a problem. I will also have the teeth on the sprocket cut with a bevel. The sprocket manufacturer assured me this was not an issue, but production units will have this feature added.

 

[chainmaker]

Nice Work Pat !!

 

[NunyaBidness]

That's very nice.
Question, will the same 3-piece part fit multiple hub sizes, as long as the hubs are close in size?

 

[sportscarpat]

That's very nice.
Question, will the same 3-piece part fit multiple hub sizes, as long as the hubs are close in size?

The adapter shown in the pictures is for the Shimano 110 hub and works on any 36 spoke Shimano coaster brake wheel. Spoke size does not create any fit problems because of the bolt circle I chose. If I continue development of this part it is a simple matter of adjusting the bore diameter to fit the various hubs that are available. So the answer to your question is no it will not fit multiple hub sizes. The bore diameter of the adapter will need to match the hub diameter. This is a simple program change for the various hub diameters.

 

[matthurd]

how exactly do these work? i know it supposedly spins the wheel instead of the spokes, but i don't really see it grabbing onto anything. just the bolting areas running through the spokes(like the kit rag joints), which imo would be worse for the spokes since it's only 3 places to drive with instead of 9.

what am i missing here? never used one so my view is based solely on what i can see.

 

[GearNut]

It looks like it will work quite well, and is strikingly similar in appearance to manic's adapter.
I like the fact that one does not need to bend the brake arm for clearance in your design.

 

[corgi1]

the adapter looks great
I was thinking along those lines the other day ,the difference I was thinking was a disk hub mount as shown ,with the 3 properly spaced holes same as the sproket with 3 thick stand off tubes and bolts going through the sproket ,the standoffs ,and center hub disk ,with nuts on the bolts inside the spoke area
And wondering about different shims for different hubs,a machined center grove should hold them in place with a raised ridge around the shim

 

[Venice Motor Bikes]

I'm glad this is finally here!
It's about time that we had a better option for rear sprockets & adapters.

 

[Goat Herder]

Awesome now I finally wanna try one. I one want one!

 

[corgi1]

How long is testing,or until they are available,and a guess at price??

 

[sportscarpat]

Price? Not yet determined. This is just a prototype for testing purposes, but with the nature of the equipment used to produce it I can make just one or thousands of them. I feel this is a key component of every motor bike build and it should not be something that is hard to aquire. If I need key components for my builds and they are readily available I will just buy them. If not, I will build what I need. If I can help others in the same situation then I will. This is a big hobby and it is starving for quality components. There is room enough for everybody.

 

[sportscarpat]

Hey guys, I am just showing pictures of a sprocket adapter here. I do my best to avoid controversy and will continue to do so. I am looking for feedback on my design so that I can improve it before giving further consideration to making them available to others. Let's stay focused and be constructive for the sake of everybody. So, along those lines I have some thoughts I would like some feedback on.

1. The width of the adapter clamping surface is 3/4". Because of the three piece design the parts are small and easily fit into the hub area through the spokes. It seems only obvious to me that I can increase this width to increase the clamping area for higher h.p. applications. Should I?

2. The sprocket is aluminum to keep costs down. I can have them made in steel as well. If a steel sprocket was twice the cost would anyone care to spend the extra money for a more durable part?

3. Since the parts are aluminum they can easily be anodized. This would also add cost. Would anyone be interested in an anodized version for a few dollars more?

4. I have always ran 40 tooth sprockets for all my China engine builds. do most people run a 40t or 45t? Do we really need dozens of different size sprockets? What basic sizes do we need?

Thanks,
Pat

 

[corgi1]

(4) larger people,trailers ,trikes,and hilly country will need larger sprokets,I don't remember a tooth count(56/60 ?) large size,,I guess the standard kit (40 tooth ?)and the 36 are the next ones talked about the most(go too #2)

(2) there are many steel sprokets out there,so could there be an adapter plate to go on in place of the sproket ,to bolt a steel gear onto?........(maybe with a little wider main 3 piece hub and a really large adapter plate it could go a belt drive shieve)

****Do the insides of a 110 hub friction brake in the hub have "fine grooves"to increase the gripping power of the metal to metal brake shoes ?(kind of like the sipes on a tire,lots of gripping lines all the way around the inside, verses a flat hydroplane (slipping) type of surface of a wide bald tire?)

(1) Width ?if the other ones are gripping correctly from pirate and are only 3/4 inch then these should be ok for most ,or maybe a wider HD one also or bolt on blocks to widen it

(3) color is always nice as a drawing card( I mostly lean toward black and silver)

 

[silverbear]

I've used a couple of the Creative Engineering adapters and sprockets and been very happy with their quality and performance. I've also admired Pat's work and have his first in frame gas tank for a Panther... awesome. Seeing options available to us, including the pineapple adapter, is a real good thing, in my opinion. This forum alone has over 28,000 members and many of us have multiple builds. That's a lot of motored bikes and the market is growing. I think there's room for everybody. Wishing you success, Pat, and continued success and innovation, Jim, at Creative Engineering.
SB

 

[silverbear]

Regarding sprocket sizes, the EZMotors Qmatic transmission comes with a 56T sprocket and some of us use a bigger one yet for hill climbing capability... 64T. AZBill uses a 72T sprocket for hills while towing grand kids in a trailer. Don't forget the needs of the four strokers. Not everybody is running China girls or is going for top speed.
SB

 

[worksmanFL]

I fully expected this to have at least a little controversy attached to it, but after having many builds of my own held up because I could not aquire the necessary parts I just decided to make my own. It's not rocket science and I have seen the ones on ebay as well. Besides, the first thing I had to do with every adapter I ever bought was to modify it right out of the box. This version I designed truly is a simple bolt in with no modification necessary. It also just drops right into place with no spreading of spokes or fighting to just get it into place.
Pat

Kudos to you on your UPDATED design! I think you have a winner here!
Truly a "plug and play" design.

(I was also going to add the words NEW and INNOVATIVE, BUT I am NOT here to stir the pot)

Questions please:
a. Roughly when will this be available?
b. Approximate retail price?
c. Is your adapters approximate CB-E110 hub acceptable tolerances the same as other adapters- 1.522" - 1.528"?

Thank you.

Awesome and 2 thumbs up!

 

[sportscarpat]

Are the sprocket mounting bolt holes interchangeable with the manic mechanic sprocket?

What is the smallest sprocket you can use with your adapter?
and the big question....how much is it going to sell for?

The sprocket mounting bolts and the clam shell bolts are all 3/8". Pretty solid stuff. I used a different bolt circle than other versions. I purchase sprockets from a dedicated sprocket manufacturer and can get any size I need by supplying a CAD file. Smallest sprocket? Well, the sprocket bolt circle is 3 3/4" so just slightly larger than that. The prototypes (five of them) were resonable but not competitive in price. As for final pricing that will be based on what we learned from the prototype run. Let's just say you get what you pay for but to be a viable product I have to offer competitive pricing and I will.

 

[bairdco]

to answer some of Pat's questions, here's my observations...

1. i've never had Jim's adapter slip or move on me, so i don't think width is a big factor.

one thing i would like, is more lateral adjustment. i've had a few builds where i have the adapter as close to the spokes as possible to get the clearance and alignment i need. it just needs longer sprocket prongs. not much longer, just a little.

2. i like steel sprockets. i've got some aluminum ones that look like sawblades after only a few months. with a high performance build, they really take a beating. since most sprockets are for smaller chains, a HD #41 chain and a motor with a lot of torque deforms the soft aluminum teeth.

3. annodizing's always a cool option. i was gonna get one of mine annodized, just never got around to it. if i coulda bought one already done, i woulda paid extra. but, not much extra, 'cause i know what annodizing costs (if i had a workshop or a big garage, i'd do it myself)

4.i don't think you need to make every size possible, but definitely more than just a couple. i ride 28's and 30's, and want one even smaller for flat out top speed, regardless of the low end sacrifice.

on most other bikes, the difference between a 40t and a 41t is about an inch of chain and 1mph, so every tooth count isn't really needed. i'd make common sizes, 30, 36, 40, 46, 52...

having the option to buy any tooth count would be nice, too, as long as the cost to make a one-off wasn't too crazy.

now here's some input from me...

for no other reason than to avoid controversy, i'd try to make it look a little less like Jim's. i know it's a basic design with not much room for aesthetics, but, y'know...

i'd make the sprocket bolt pattern universal. i dunno what Andy's, or some of the other makers are, but the ability to use a kit sprocket, or any other sprocket gives a lot more options. i have a 35t from, uh, i forget, that doesn't fit anything but a rag joint, even though it has 50 holes drilled in it. so it's useless to me.

with a universal pattern, not only could you tune your gearing easily, but in the event you slip a chain and mangle a sprocket (which i've done) you can still slap your kit sprocket on to keep you riding while you wait for a new one to ship.

with very few exceptions (mostly on older bikes) the sprockets are all standardized so they can be interchangeable and invites competition and variety.

i think that's about it...

 

[muddybike]

Hey Cowboy... For being someone who's only been here since Dec 2010, you sure know a lot about whats gone on here in the past!! (Things that have deleated for a very long time!!)
In re-reading all your posts, I'm guessing YOU ARE JIM!! because you form sentences just like him & use so many of the same phrases he has in the past like "biting the hand that feeds", & you certainly singled me out right away!!!

Hmmmmmm...... could it be??

Hmmmmm gets popcorn !

 

[matthurd]

hey pat could you delete some pms so i could send you a message?