connecting sprocket to rear wheel

[joetemus]

How does everybody attach their motors to the rear wheel? I'm mounting my motor above the rear wheel, behind the seat, and I wanted to attach a southpaw gear to the left side of the rear wheel, but still keep the cassette on the right for pedaling. That way the pedals and motor are separate systems and won't make the other spin when its being ran. I have thought of a few options, but none are ideal

- option 1: buy disc brake hubs and disk brake rotors, and attach the sprocket to that. Only problems are that its expensive, and no freewheel bearing.

-option 2: make my own threaded piece to attach the bearing, and bolt it as low as possible on the spokes. I'm worried this wouldn't be strong enough if I just attach it to the thin spokes.

-option 3: break down and just attach it to the cassette, so if the motors going I have to pedal.

-option 4: "rag joint" clamp to sprockets with a sprocket attached. You can buy these parts, I'm just worried for the same reason as option 2. Also, a few places online said it was hard to get "true" anyone have experience with these?

Have you guys thought of something easier?

 

[Miles]

You can get hubs with RH thread on the right side and LH thread on the left side, here:
http://www.evdeals.com/USPD%20Drive%20Parts.htm (scroll down).

 

[Miles]

This is a good source for drive parts, too:
http://www.staton-inc.com/store/catalog/Drive_Components_and_Hardware-9-1.html
The site is a nightmare to navigate, though.......

Edit: http://www.staton-inc.com/store/products/Rear_32_Hole_14_gage_Hub_Left_and_right_hand_threads-863-27.html

 

[joetemus]

You can get hubs with RH thread on the right side and LH thread on the left side, here:
http://www.evdeals.com/USPD%20Drive%20Parts.htm (scroll down).

Would the. $49 one allow this to screw on
http://www.amazon.com/gp/aw/d/B000VSWIWE

 

[Miles]

Yes.

 

[joetemus]

This is exactly what im looking for. Solves all my problems. Thanks!

 

[turbo1889]

Miles already posted a link for you to Staton-Inc he custom machines and sells a hub that is exactly what you are talking about, threaded on both sides for freewheel, RH thread on the right side to take a standard freewheel for the pedals and a LH thread on the left side for the motor drive. I have several bikes built using those hubs of his and I can personally attest to their quality. A little expensive but A+ quality stuff. I took the time to navigate his web-site and pull individual links for you:

His Double Threaded Hubs (by spoke hole set-up):
----- http://www.staton-inc.com/store/pro...ge_Hub_Left_and_right_hand_threads-859-0.html
----- http://www.staton-inc.com/store/pro...ge_Hub_Left_and_right_hand_threads-848-0.html
----- http://www.staton-inc.com/store/pro...ge_Hub_Left_and_right_hand_threads-863-0.html
----- http://www.staton-inc.com/store/pro...ge_Hub_Left_and_right_hand_threads-885-0.html
----- http://www.staton-inc.com/store/pro...ge_Hub_Left_and_right_hand_threads-880-0.html

Then if you want him to build the hub into a wheel for you and you don't want to build your own wheel, these are the add on's he offers to add to the hub price (includes parts & labor):
----- http://www.staton-inc.com/store/pro...Lite_Double_Wall_Alum_Silver_Anod-413-21.html
----- http://www.staton-inc.com/store/pro...o_Lite_36_Hole_for_14_gage_spokes-405-21.html
----- http://www.staton-inc.com/store/pro...le_with_12_gage_Heavy_Duty_Spokes-407-21.html
----- http://www.staton-inc.com/store/pro..._20_48_Hole_Rim_width_is_1_Silver-375-21.html

Then he also sells a high quality strong roller bearing sprag clutch style LH thread freewheel unit that is a really good price and I can personally confirm is good for at least 2-Kw of power that has the semi-standard 5-hole pattern for mounting big tooth count sprockets:
----- http://www.staton-inc.com/store/pro...HAND_thread_freewheel_sprag_clutch-967-0.html

Then he sells a couple of big heavy #35 and #40 chain sprockets from him with the 5-hole pattern to fit. But I'm not going to link to those because it sounds like you want to use bicycle type chain not the heavier duty industrial chain that he usually uses. In which case you should buy a bicycle chain sprocket or chain-wheel adapter to fit the five bolt pattern from Sick Bike Parts:

----- http://www.sickbikeparts.com/catalo...ducts_id=65&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ducts_id=66&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ducts_id=36&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ducts_id=38&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ducts_id=67&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ucts_id=163&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ucts_id=164&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ucts_id=165&osCsid=e21tpvlsuuiokst9pggqn0d280
----- http://www.sickbikeparts.com/catalo...ducts_id=89&osCsid=e21tpvlsuuiokst9pggqn0d280

Obviously if you went with one of the chain-wheel adapters you then need a chain-wheel to fit (or more correctly get chain-wheel first and pick correct adapter to go to the semi-standard five bolt patter to mount).

All that assumes you need to get some gearing reduction from the motor to the rear wheel and thus need a big sprocket on the rear for the motor. If you don't then you just need a 1.37x24tpi Left Hand threaded freewheel (usually 16-20 tooth count options), bike parts places sell them and Staton-Inc does as well but you have to pick through his catalog to find them and I picked through for some links for you since I kind of already knew where they were already in his catalog but I'm not going to find all of the links for you and you do need to realize his catalog does change from time to time and different items come and go or are in-stock, out-of-stock.

 

[turbo1889]

Well, looks like I missed some discussion while I was writing that big long post and collecting all those links for you. The cheaper stuff from the other link will work I'm sure but I personally prefer the higher quality and replaceable cartridge bearing arrangement of the Staton-Inc double threaded hubs.

You sure that little small tooth count LH thread freewheel you linked too off of amazon is going to work for you and you don't need a lot bigger sprocket on the rear wheel to get your drive ratio right? Very few is the motor that doesn't need to be geared down to the wheel in my experience. And if you do find you need a bigger sprocket then you can still pick up the LH threaded good priced 5-hole pattern sprag-clutch roller bearing freewheel unit from Staton-Inc and combine it with a big tooth count 5-hole disk sprocket from Sick Bike Parts on the cheaper hub from the other place so those links will still be good for you if you find you do need a bigger tooth count on the wheel to get the gearing right.

 

[neptronix]

I used a recumpence disc brake adapter ( $85 ) and a custom sprocket ( ~$70 ), which gave me a fat #41 66T sprocket on the back of my wheel with the proper offset to avoid the chain or sprocket from bumping up against the chainstays.

I found that disc brake sprockets max out at about 35T or so because it will hit the chainstays on most bikes if larger than that. I wasted money on the clamshell adapter, and that was a bust too.

 

[joetemus]

Well, looks like I missed some discussion while I was writing that big long post and collecting all those links for you. The cheaper stuff from the other link will work I'm sure but I personally prefer the higher quality and replaceable cartridge bearing arrangement of the Staton-Inc double threaded hubs.

You sure that little small tooth count LH thread freewheel you linked too off of amazon is going to work for you and you don't need a lot bigger sprocket on the rear wheel to get your drive ratio right? Very few is the motor that doesn't need to be geared down to the wheel in my experience. And if you do find you need a bigger sprocket then you can still pick up the LH threaded good priced 5-hole pattern sprag-clutch roller bearing freewheel unit from Staton-Inc and combine it with a big tooth count 5-hole disk sprocket from Sick Bike Parts on the cheaper hub from the other place so those links will still be good for you if you find you do need a bigger tooth count on the wheel to get the gearing right.

I'm using a my1020z3 motor, which is already geared down, and I have been told by quite a few people on here that a 1:1 ratio works great on these motors, because their max rpm is 480, with load around 325-350. I then decided I go from from a 14t on the motor to a 16t on the hub, so I'd get some more acceleration. So I'm going to assume this gear ratio will be good.

Edit: also my bike was built in 1967 so it doesn't have disc brake holes.

 

[joetemus]

I used a recumpence disc brake adapter ( $85 ) and a custom sprocket ( ~$70 ), which gave me a fat #41 66T sprocket on the back of my wheel with the proper offset to avoid the chain or sprocket from bumping up against the chainstays.

I found that disc brake sprockets max out at about 35T or so because it will hit the chainstays on most bikes if larger than that. I wasted money on the clamshell adapter, and that was a bust too.

I'd go this route if i had disc brake holes, but my bike was built in 1967, so the hubs do not have holes for the disk brakes, so I was unable to do this. I'd also like to have a freewheel so that the motor resistance wasn't a problem when I wanted to just pedal.

 

[recumpence]

The way my systems avoid the motor drag is by installing the freewheel on the output of the reduction unit.

Your situation is a little bit different.

Matt

 

[neptronix]

Maybe you should go with a stronger, more modern bike O_O

I used a recumpence disc brake adapter ( $85 ) and a custom sprocket ( ~$70 ), which gave me a fat #41 66T sprocket on the back of my wheel with the proper offset to avoid the chain or sprocket from bumping up against the chainstays.

I found that disc brake sprockets max out at about 35T or so because it will hit the chainstays on most bikes if larger than that. I wasted money on the clamshell adapter, and that was a bust too.

I'd go this route if i had disc brake holes, but my bike was built in 1967, so the hubs do not have holes for the disk brakes, so I was unable to do this. I'd also like to have a freewheel so that the motor resistance wasn't a problem when I wanted to just pedal.

 

[boostjuice]

Then he also sells a high quality strong roller bearing sprag clutch style LH thread freewheel unit that is a really good price and I can personally confirm is good for at least 2-Kw of power that has the semi-standard 5-hole pattern for mounting big tooth count sprockets:
----- http://www.staton-inc.com/store/pro...HAND_thread_freewheel_sprag_clutch-967-0.html

That's not a sprag clutch, but a standard Dicta cheapie ratchet/pawl freewheel. The same as is sold with Cyclone kits. Just wanted to correct this because my surprise was deflated when I realized it was nothing new.

 

[joetemus]

Maybe you should go with a stronger, more modern bike O_O

I have built in extra supports, and only plan on a top speed of around 30. This is just a test bike, and I plan on building a much better platform on my trek 4500 once I get the experience and the money to build it properly.
I just started a build log here http://endless-sphere.com/forums/viewtopic.php?f=28&t=54826

 

[turbo1889]

Then he also sells a high quality strong roller bearing sprag clutch style LH thread freewheel unit that is a really good price and I can personally confirm is good for at least 2-Kw of power that has the semi-standard 5-hole pattern for mounting big tooth count sprockets:
----- http://www.staton-inc.com/store/pro...HAND_thread_freewheel_sprag_clutch-967-0.html

That's not a sprag clutch, but a standard Dicta cheapie ratchet/pawl freewheel. The same as is sold with Cyclone kits. Just wanted to correct this because my surprise was deflated when I realized it was nothing new.

I've bought several from him and although I haven't torn one down they are silent with absolutely no clicking and the engagement is not a hard "smack" lock but rather a steady tightening until full tight over about a 10-degree arc. Sound and feel like a sprag roller clutch to me. Although it is true that I haven't bought from him in the last 6-months or so, could be he has changed stock in that time. You do realize of course that he does indeed also sell the same ratchet type as cyclone does with a Right Hand Thread. The Left Hand Thread one that I linked too is the one that is a sprag roller clutch as far as I can tell from the ones I've bought from him. To my knowledge he is the only one selling these units (freewheel thread to five hole sprocket freewheel units) with a 1.37"x24tpi Left Hand Thread. Everyone else seems to only sell various versions with right hand threads.

Again, I haven't torn one down but by feel (how it locks up not as a hard lock but as a 10-degree arc tightening down feel) and how it sounds (silent no click, click, click when freewheeling) its a true sprag clutch roller bearing unit not a conventional freewheel, at least as of 3-years to 6-months ago which is the course of time over which I've been buying them from him. Also, again, they are LH threaded not the conventional RH thread so they won't work for a front crank freewheel assembly screwing on to the inside of the right crank arm RH threads like Cyclone uses but rather you have to put a LH thread adapter on an the bottom bracket stub-axle and screw the unit onto that then put a conventional crank arm over the top of it which is how the Staton-Inc freewheeling bottom bracket kit is set-up actually but it is actually more used for mounting large tooth count sprockets on the left side of his double threaded wheel hubs for good reductions from motors putting a small tooth count sprocket on the motor (he mainly does gas motors but a lot of his parts work just as well for electric builds and some stuff you can get from him I haven't found anyone else selling).

 

[boostjuice]

Ok, that's interesting. Cosmetically it looks identical. I'm surprised it doesn't have a different form factor considering the extra space that sprag/cam clutch's need for equivalent torque holding as ratchet/pawl.

 

[RC_guy]

Hey Turbo,
Do you think thoses sprag clutches would be reliable at 3kw peaks, only when accelerating and 1500w cruising?
How much power do you run through them and how many miles have you run?
Also is the resistance of spinning freely better or worse than a regular freewheel?

Thanks...That is pretty much exactly what I was looking for

 

[orange streak]

The best sprocket attachment methods are important, and it works around your brake setup, clearance, & reliability. With that said, you should really get a rear wheel sprocket that bolts on only, so you eliminate be stranded on a dirt road with a sprocket that has unthreaded itself or striped off!, which has happened to me.

I can run my mid drive motor on both sides of the wheel with my mounting kit with dual freewheels on eighther side of shaft, just in case you want the wheel to spin more freely with out turning over the motor. But the better method is to have a wheel with dual disk brake flange holes type hub laced in, so you can keep your disk brake on the left side, then you can use the right side for your sprocket to bolt on to, & then afterwards also bolt on a freewheel adapter to thread on to for just peddling use.
This does the trick for me, as long as you have the clearance for at least a five speed freewheel, you can yank on the throttle very hard, the only limiting factors can be spoke strength, & bicycle chain breaking maybe at 15hp! & you get to keep you disk brake, & I also use a rear rim brake for more stopping power for my 7kwh e-bike! :wink: