Cannonballs Abbynormal 3Speed.

GoldenMotor.com

cannonball2

Well-Known Member
Oct 28, 2010
3,682
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Colonial Coast USA.
Thanks to you all for the kind comments and encouragement!

This was a fairly easy conversion of the hub. There is nothing special about any of the parts used, and I was able to avoid a machine shop visit. This means anyone with average or better mechanical skills can do the same. The mount for the hub is the only specialized part, and its very simple. I suppose a bolt together version is possible for the non welders out there.
This build is one where all the elements came together well. The bike itself is a very nice rider, the engine is an excellent runner and the hub works great! Once the shifter is worked out it will operate very nicely. Will know about that today.
With the ability to pull higher final ratios, it would seem that a well running stock engine would be capable of speeds in the low to mid forties. The calc. shows a 43mph top speed with a 30t rear @7000rpm and 48@8000 and 54@9000 for modded engines.
Shifter bikes are nothing new, and running IGH hubs with them isn't either. This build greatly uncomplicates the machine.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
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northeastern Minnesota
CB2,
I think what you and your partners in crime have come up with is a real breakthrough. Yes, someone will figure out a non welded mount and maybe someone else will make up mounts like yours for sale. I like your mount a lot.

I'd consider such a build, but have pretty well written off China girl engines due to the vibrations and the effect it has on my hands. I've come to appreciate four strokes and can imagine that a 79 or 99 predator mated to this hub would give nice results. Even a 50CC Hua Shung, but I've also come to like the older flat head Briggs and Tecumseh engines. I wonder how strong that hub is. How do you think shifting would be with a centrifugal clutch?
SB
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
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Colonial Coast USA.
SB, I think the hub is pretty stout. I inadvertently shifted from second to first when I was wound out for a third shift. Seem to take it just fine.

Its unknown just what it will handle but I think lower hp 4stokes would be fine especially with a centrifugal clutch. The standard IGHs have been run a long time on shifter bikes at the rear wheel where they are loaded more than in the transfer position and this hub is much stronger. A Briggs or Tecumseh 3/3.5hp would be ideal I think. I think cent. clutch shifting is ideal. In fact I ordered one for the CG engines yesterday.
I am also going to convert this engine to the wet clutch set up first. It is so much smoother and gradual on the take up than the stock dry clutch.

When you get hands on your SA hub to count the speeds in reverse we can do a build around one of them since they are common and cheap.
 
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Dec 11, 2014
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Cannonball, I started shopping the 3 speed shimano hub on Ebay yesterday. I think I am definitely looking forward to building a bike around one. Keep the updates coming as to how it holds up. I plan to mount it pretty much the same way you did. I may still try to squeeze one into this bike. I might be able to add it to the bike without too many other significant changes so in the event of a problem I could remove it and run direct single speed again if I had too. Once again my compliments to your work.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
SB, I think the hub is pretty stout. I inadvertently shifted from second to first when I was wound out for a third shift. Seem to take it just fine.

Its unknown just what it will handle but I think lower hp 4stokes would be fine especially with a centrifugal clutch. The standard IGHs have been run a long time on shifter bikes at the rear wheel where they are loaded more than in the transfer position and this hub is much stronger. A Briggs or Tecumseh 3/3.5hp would be ideal I think. I think cent. clutch shifting is ideal. In fact I ordered one for the CG engines yesterday.
I am also going to convert this engine to the wet clutch set up first. It is so much smoother and gradual on the take up than the stock dry clutch.

When you get hands on your SA hub to count the speeds in reverse we can do a build around one of them since they are common and cheap.
Excellent! Should I be looking at just the S.A. coaster brake type 3 speed hub (SC3)?
SB
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
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Colonial Coast USA.
Thanks LSR!
I don't know much about the Shimanos other than it is or was known to be weaker than an SA. We have two of the newer hubs on our pedal bikes and they work well. I have an older one I have repaired and it is lightly built. The hubs are in less loading when used in the transfer position so maybe any type would work. If you have the room behind the seat post, using a mount with the lock collars will allow the flexibility to add or remove the system. This is a good plan to pull higher ratios for your Bonnie bike.

SB.
I honestly never messed around with IGHs until now so Im not well versed on whats really out there. The coaster hub can have the brake removed, but the brakeless hub like used on the "English" type bikes would be probably better. That's like the Shimano hub I have that started all this. Im inclined at some point to add this one to my test mule bike. As it is it would only be a 2speed but that's better than 1!
 
Dec 11, 2014
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I dont know why i said or was looking at the shimano. I want to do the sturmey fixed 3 speed just like yours. I guess just so many years of shimano it sticks in my brain. The sturmey is the only fixed option.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
Got a few more miles on the bike. Got all the details attended to, like soldering the ends of the many custom cut cables to keep them from fraying, adjusting the twin pull brakes for even pull, and installing the SA thumb shifter.
The thumb shifter is mounted on the right ahead of the hand brake handle. It works fairly well there. The throttle is backed off for shifting so the right thumb is free to shift. I clutch all shifts. The lack of play in the drive train is really nice, shifts are basically jerk free. With the 40t rear sprocket starting in first is unnecessary. Second works just fine. That led to the conclusion that the bike is under geared. I ordered a 32T sprocket. Might as well go tall on the gearing, don't think it will have a problem pulling it. First should be necessary with the 32.
Im kind of evaluating two things at once the hub and engine. I REALLY like the GT5. It has run flawlessly from the get go. Seems to have plenty of bottom end for an unbroken in engine, and is very smooth from the bottom to as high as I have dared take it. Its absolutely nothing like the Flying Horse which isn't bad but not in the same league. I still have my other box built GT5 yet untested. It has the SKF bearings and the lightened piston. Should be a bit smoother still.

Also ordered some 1.95 combo type tires to replace the little 1.5s that sould up the ratio a tiny bit also.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
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http://sheldonbrown.com/awfixed.html

CB2,
You've seen the above link before, but for the purposes of this post I thought I'd insert it again. It is a less than thorough description of how to convert a common Sturmey Archer AW 3 speed internally geared hub as found most often on old English 3 spd bikes. These are not hard to find. So, the conversion is from a freewheel to a "fixie" type of hub. The conversion ends up with two gears which would in effect be something like the old Bendix 2 speed hub with hi and low. For most of us that would be enough to make a world of difference on our motored bikes, allowing for a higher top end speed at lower engine rpms... quieter and less wear. Low for starting out and hill climbing, and high for cruising.

I do wish someone would make this conversion with detailed photos and clear how to commentary. It would mean a lot for those of us on a budget to have a way to do this ourselves. I see in the description the word "machined" and for most of us that is a turn off since we have hand tools. But maybe hand tools are enough. Maybe a file or a little rotary tool (Dremel is one) along with effort and patience can do the "machining" necessary. Maybe this conversion is not so daunting as one might imagine. I don't know and I would like to know.

CB2,
You are obviously a capable guy with a lot of know-how and intuitive understanding of mechanics. Some of us who read this thread, see what you have done, try to follow the discussion with others who are knowledgeable are left scratching our heads, trying to understand. I'm one of those kids in the back of the class trying to understand, but not quite making it. I do know that my checkbook will not allow me to send off for the hub you used. That's out. But I do have some old S.A. hubs I've salvaged. The only one at hand is a coaster brake model, which I understand is not what we're looking for. The old AW model is freewheeling and was supposedly fairly robust and well made. Also parts are readily available. So, once I can dig through my "stuff" I'll be looking for an AW. It seems like a good choice to experiment with since it is the most common. I'll look for two of them and will be happy to send one to you. Would you try to make the conversion and document with pictures and words what you're doing? And if you see how things can be done with a hand tool instead of a lathe, can you keep us poor boys in mind?

A couple of questions. First, what exactly is a "fixie" hub? Why is that what we need for using the hub as an external transmission? (I'm guessing that flipped over it would not drive the wheel, but would "freewheel", is that right?)
Once the internal modifications are made would we do what you have done by flipping the hub over so the sprockets are on the left hand (engine driveline side)? Would we mount the sprockets in the same way you did?

I know it is asking a lot for you to back up and do this conversion, but if you would I suspect there would be many of us digging around for an old AW hub to convert. The high dollar SX3 is a fine thing with it's three speeds and it would be a thrill to find one in my mailbox. But the freebie AW hub with two speeds is also a fine thing if we can make it happen. Think about it, eh? I'd like to do one, but don't have the confidence to do it without a mentor, photos and such.
SB
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
Thanks for the kind compliments SB! I have been cobbling stuff together that's not supposed to do what I want it to do since I was a kid. I like the challenge.

The fixie hub is a locked hub, there is no freewheeling. That's why its happy to work on either side/or direction of rotation. When taking a common freewheel 3spd and turning it around to work on the left the normal sprocket will just freewheel driving nothing. However if you add a sprocket to the hub shell and drive that then the hub will drive the original sprocket. I have only had hands on with the elderly Shimano hub. When rotated by the hub it only has 2 speeds(actually 3 but 2 are the same) Direct and overdrive. This is still very usable with the proper gearing. Gear the bike a bit lower than normal for good take off/climb, then the OD will increase the top end.
Its hard for me to visualize the AW conversion with out hands on. I was really after the simplicity of using a 3spd as is and driving the hub will allow this. The down side is no pedal start capabilities as it freewheels when the wheel is turned. Another issue or advantage depending on ones perspective is the bike will freewheel when off throttle. Seems however most builds can be pull started.

The AW converted to a fixie would probably be ideal, that's is basically the idea behind the S3X.
 
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cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
OK SB I have studied the AX conversion and I THINK I got it. Having machine capabilities makes the conversion more civilized, but I think the same results could be had by pinning the two pieces together with something as simple a few set screws drilled in from the outside of the hub into matching holes in the gear carrier. Heck probably one might do it, but threes not that much more difficult.

That is if I am thinking correctly(I believe so).
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
Heres a pic of the "finished" bike(they never really are). It will soon get a disc brake front wheel.
The pics of the shifter showing the travel, has quite a bit. First pic is low, second pic is high. Second gear is in the middle. Low is a bit of a reach but not bad and is mainly selected at a stop, the rest of the shifting is done between third and second for the most part.
This bike has turned out so well functionally that its worth investing a little$$ in to make it first class operationally. I bought a clamp on sprocket adapter last night from Kings MBs at a good price. Comes with a 36t sprocket. They had the size for the common MTB freewheel hub, not so easy to find. I hope to be able to drill the common CG sprockets to fit the adapter so I can continue to run the BMX chains. We will see.
 

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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
CB2,
What is AX?

Just looked through my hubs and see that two of them are shimano F types, one S.A. WA(freewheel) type, one S,A. SC3 (coaster brake) type and one Bendix 2 speed. There is also one English bike with an unidentified freewheel type 3 speed buried in snow. Might be one or two more tucked away under tarps also buried in snow.

Your bike looks good... such a clean setup.
SB
 
Dec 11, 2014
628
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Tucson
I just love this bike Cannonball and how well it is working for you. I really really really want to start my next build and run one of these hubs. My plan is the Skyhawk frame with built in tank. Fit twin pocket bike engines with snake pipes in the front triangle. The performance version of these motors are $150 and come with centrifugal clutches. I am thinking if they ran to the SA 3 speed onto one tooth diffferent sprockets i would get a wide powerband and close to 8 horsepower for $300. Rigid triple crown front fork, wide 24" wheels, anyway that is my dream street bike build that I am picking up parts for here and there, and it's made much better with your SA 3 speed jackshaft idea.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
Sorry SB, I meant AW! Any freewheel type is a candidate, check the SA WA turned backward by the hub and see what you get for speeds.

LSR I had one of those tuned PB motors, it didn't last too long but then I don't think I treated it very well. That's one to for sure helicoil the cylinder studs, mine pulled in the first 5 min!

IWW(aka Steampunk girl-love it!) I would have to name that twin Whizzer "Whizzed Off" if it was mine. Too cool!
 

bowljoman

New Member
Aug 7, 2010
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Old hubs can work, as in sheldon's conversion, but longevity is unknown. New hub designs use roller clutches instead of pawls. Old SA hubs have a dead spot if not adjusted properly that can develop into a full neutral gear.

I really recommend purchasing a new or getting at least a modern hub and particlarly, using the S3X hub for left hand drivers.

I have doubts in the realm of the reverse drive for coaster/freewheel hubs.

If one cant acquire the S3X for budget, then consider rear-rack mounting with enough offset to forward drive a tricycle transmission, or consider the 2-strokes that output on the right side using a 5 to 1 reducer, centrifugal clutch, and driving the right side(convert peddles into pegs, since gears push the bike into illegal ville anyway :).

In the end, the tranny seems cheaper than an engine that is modded to reach the same speeds with added reliability. So dont be affraid to splurge on it. GET THE RIGHT PART the FIRST TIME, or you wont have a good time.