Rear rim sturmy archer help please

BSAmase

Member
Sep 27, 2018
59
22
8
32
Hello again all I have a standard size rear rim with a sturmy archer one speed pedal back style break in the hub. What I am wanting to know and do is I want the rear sprocket which is on the right hand side of the rim to be switched to run on the left hand side is this at all possible If it helps i dont need the hub break as I could hook up hand breaks if neccesary
 

MotoMagz

Well-Known Member
Aug 2, 2010
1,747
929
113
Michigan
Hey, I don’t think so... but anything is possible! If it had a freewheel you would have more options. Maybe have a Moderater move to Wheels and brakes section. Good luck
 
  • Like
Reactions: BSAmase

indian22

Well-Known Member
Dec 31, 2014
3,824
4,552
113
Oklahoma
Hello again all I have a standard size rear rim with a sturmy archer one speed pedal back style break in the hub. What I am wanting to know and do is I want the rear sprocket which is on the right hand side of the rim to be switched to run on the left hand side is this at all possible If it helps i dont need the hub break as I could hook up hand breaks if neccesary
The quick answer is yes you can. My question is what do you hope to accomplish by the flip/flop? Depending on your answer to this question will determine if it's a decent project to tackle & that's up to you. My opinion is that a hub adaptor/sprocket or even a kit rag joint is a better all round choice

My assumption (which might not be your goal) is that you want to drive the China girl with either the tiny existing pedal chain sprocket, or adapting a larger sprocket to mount up to the Sturmy sprocket. Remember that pedal starts are eliminated with the wheel flop. The extremely small Sturmy sprocket is a really poor choice to attempt a motor drive with. Even if the pitch is correct the width is far too narrow and the small diameter will just not work on any terrain other than flat or downhill. If either of these assumptions are correct then read on.

The coaster brake lever will need to be cut off (not removed) forming a washer/spacer & left in place. The wheel is at this point free to rotate in either direction with no need to remove the internals of the hub, if the brake lever washer previously described is left in place. If you decide to eliminate the hub brake internal parts then appropriate internal spacers have to be added which is a bit of a pain & I don't recommend. Depending on the wheel "dish" and chain to tire clearance required, the stock sprocket needs to be removed & at this point hubbearings inspected and replaced if necessary and grease repacked. Then the axle adjusted to center the wheel, then sprocket replace and spacers installed as needed.

Much more involved with adding brakes, getting a sprocket set up etc. but the wheel flop itself has been done before with deactivation of the coaster brake. I recall a bicycle that even flopped the pedal sprocket to the left side as well. For what reason I know not. Good luck on the BSA...I like. Rick C.
 
  • Like
Reactions: fasteddy

BSAmase

Member
Sep 27, 2018
59
22
8
32
Thanks heaps mate buying a rolling frame this coming weekeng ill be sure to pick a tidy looker on the second project hoping for triumph. Your description is great I will be sure to test as I go and plan better than the last as it needs to better the last bsa cheers
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
The quick answer is yes you can. My question is what do you hope to accomplish by the flip/flop? Depending on your answer to this question will determine if it's a decent project to tackle & that's up to you. My opinion is that a hub adaptor/sprocket or even a kit rag joint is a better all round choice

My assumption (which might not be your goal) is that you want to drive the China girl with either the tiny existing pedal chain sprocket, or adapting a larger sprocket to mount up to the Sturmy sprocket. Remember that pedal starts are eliminated with the wheel flop. The extremely small Sturmy sprocket is a really poor choice to attempt a motor drive with. Even if the pitch is correct the width is far too narrow and the small diameter will just not work on any terrain other than flat or downhill. If either of these assumptions are correct then read on.

The coaster brake lever will need to be cut off (not removed) forming a washer/spacer & left in place. The wheel is at this point free to rotate in either direction with no need to remove the internals of the hub, if the brake lever washer previously described is left in place. If you decide to eliminate the hub brake internal parts then appropriate internal spacers have to be added which is a bit of a pain & I don't recommend. Depending on the wheel "dish" and chain to tire clearance required, the stock sprocket needs to be removed & at this point hubbearings inspected and replaced if necessary and grease repacked. Then the axle adjusted to center the wheel, then sprocket replace and spacers installed as needed.

Much more involved with adding brakes, getting a sprocket set up etc. but the wheel flop itself has been done before with deactivation of the coaster brake. I recall a bicycle that even flopped the pedal sprocket to the left side as well. For what reason I know not. Good luck on the BSA...I like. Rick C.
Would trying to run a standard sprocket which I have just wrapped the chain around and bites well with very little movement side to side mean the bike would basically be trying to rotate the rear wheel much to fast...if it workd to begin with? Which in saying that yes it would be harder to start as youd almost need to bump start the rear wheel. No hills or inclines around my area only long flat roads and speed will be a big part of the next 98cc villiars engine build
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,549
238
63
living the dream in southern california
The quick answer is yes you can. My question is what do you hope to accomplish by the flip/flop? Depending on your answer to this question will determine if it's a decent project to tackle & that's up to you. My opinion is that a hub adaptor/sprocket or even a kit rag joint is a better all round choice

My assumption (which might not be your goal) is that you want to drive the China girl with either the tiny existing pedal chain sprocket, or adapting a larger sprocket to mount up to the Sturmy sprocket. Remember that pedal starts are eliminated with the wheel flop. The extremely small Sturmy sprocket is a really poor choice to attempt a motor drive with. Even if the pitch is correct the width is far too narrow and the small diameter will just not work on any terrain other than flat or downhill. If either of these assumptions are correct then read on.

The coaster brake lever will need to be cut off (not removed) forming a washer/spacer & left in place. The wheel is at this point free to rotate in either direction with no need to remove the internals of the hub, if the brake lever washer previously described is left in place. If you decide to eliminate the hub brake internal parts then appropriate internal spacers have to be added which is a bit of a pain & I don't recommend. Depending on the wheel "dish" and chain to tire clearance required, the stock sprocket needs to be removed & at this point hubbearings inspected and replaced if necessary and grease repacked. Then the axle adjusted to center the wheel, then sprocket replace and spacers installed as needed.

Much more involved with adding brakes, getting a sprocket set up etc. but the wheel flop itself has been done before with deactivation of the coaster brake. I recall a bicycle that even flopped the pedal sprocket to the left side as well. For what reason I know not. Good luck on the BSA...I like. Rick C.
If you "hack off the brake arm and use it as a washer" the internals will engage and your bike will start pedaling forward, which would be very dangerous at speed.

I've broken the strap that holds the brake arm to the frame before, and it's a very unpleasant experience. Think pedaling backwards to stop, and suddenly the pedals move forward like a fixie. It can pitch you over the bars, or bust up your ankles and shins when the cranks start spinning.

There used to be a product called an "unbrake" for bendix hubs that turned it into a "free-coaster" in the early days of bmx freestyle. It eliminated the braking action, and the pedals didn't turn backwards when you fakied (rolled backwards.)

Best bet is to get a flip flop hub, or use an adapter.
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,549
238
63
living the dream in southern california
Hello again all I have a standard size rear rim with a sturmy archer one speed pedal back style break in the hub. What I am wanting to know and do is I want the rear sprocket which is on the right hand side of the rim to be switched to run on the left hand side is this at all possible If it helps i dont need the hub break as I could hook up hand breaks if neccesary
There's really no way to flip a coaster brake hub to the other side, without welding the sprocket to the hub itself, and remove all the brake guts. Which would eliminate pedaling and coasting.

Early Sachs mopeds used a Durex coaster brake hub that had a drive sprocket on the left, and pedal sprocket on the right. They pop up on eBay now and then, but usually aren't cheap.

Bottom line for using a small sprocket, is you need enough torque to move it. If you have the HP but no torque, you'll "freight train" up to speed. Meaning, it'll take a while to get up to speed where the engine can finally push it.
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
If you "hack off the brake arm and use it as a washer" the internals will engage and your bike will start pedaling forward, which would be very dangerous at speed.

I've broken the strap that holds the brake arm to the frame before, and it's a very unpleasant experience. Think pedaling backwards to stop, and suddenly the pedals move forward like a fixie. It can pitch you over the bars, or bust up your ankles and shins when the cranks start spinning.

There used to be a product called an "unbrake" for bendix hubs that turned it into a "free-coaster" in the early days of bmx freestyle. It eliminated the braking action, and the pedals didn't turn backwards when you fakied (rolled backwards.)

Best bet is to get a flip flop hub, or use an adapter.
Thanks mate yhea looks like theres going to be plenty of spare rims to choose from at the old bike shop where im shopping for the new bike so Ill find a new rim to suit left side drive probably of a slightly more modern bike for saftey
 

indian22

Well-Known Member
Dec 31, 2014
3,824
4,552
113
Oklahoma
The pedals can't turn if they aren't attached to the rear wheel via a pedal chain, which is eliminated with this wheel flop. The coasters I've used, in the manner I described in my prior post rotated freely in both directions free of any noticeable internal drag with all internal brake/ hub parts left in place. As I also stated the internals can be removed as well; up to the builder, but I noticed no difference in use, one way or the other. Pedals can be "locked level" and equal since 180 degrees out of phase is no longer required for pedal operation.

As to using the stock Sturmy sprocket with the China kit drive chain. Some old wheel sprockets are a little wider & might be ok for use. Chain & sprockets will wear faster and the chain might try to rub the tire, so a little extra room between tire and chain is a good thing as well. It sounds as though "pitch" is correct between chain and sprocket so all's well in that dimension.

I agree that that the stock China girl motor won't have enough torque to get you moving. Even the highly modified motors have a hard time off the line without the aid of manual pedal assist on flat terrain using 34 or 36 tooth final drive sprockets. Consider it from this point. Count the teeth on the motor sprocket and on the wheel sprocket and divide the two numbers. If the number you come up with is less than 3 you must have active pedals and clutch slip to get you moving. A lot of clutch slip will quickly burn your clutch, but I'm afraid you will really not enjoy riding your BSA as a result of going this direction & that would be a shame as I really like the bike.I also admire your willingness to try something different. .

Rick C.
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,549
238
63
living the dream in southern california
The pedals can't turn if they aren't attached to the rear wheel via a pedal chain, which is eliminated with this wheel flop. The coasters I've used, in the manner I described in my prior post rotated freely in both directions free of any noticeable internal drag with all internal brake/ hub parts left in place. As I also stated the internals can be removed as well; up to the builder, but I noticed no difference in use, one way or the other. Pedals can be "locked level" and equal since 180 degrees out of phase is no longer required for pedal operation.

As to using the stock Sturmy sprocket with the China kit drive chain. Some old wheel sprockets are a little wider & might be ok for use. Chain & sprockets will wear faster and the chain might try to rub the tire, so a little extra room between tire and chain is a good thing as well. It sounds as though "pitch" is correct between chain and sprocket so all's well in that dimension.

I agree that that the stock China girl motor won't have enough torque to get you moving. Even the highly modified motors have a hard time off the line without the aid of manual pedal assist on flat terrain using 34 or 36 tooth final drive sprockets. Consider it from this point. Count the teeth on the motor sprocket and on the wheel sprocket and divide the two numbers. If the number you come up with is less than 3 you must have active pedals and clutch slip to get you moving. A lot of clutch slip will quickly burn your clutch, but I'm afraid you will really not enjoy riding your BSA as a result of going this direction & that would be a shame as I really like the bike.I also admire your willingness to try something different. .

Rick C.
When you say "rotates freely in both directions," do you mean with the chain attached to the flipped wheel via the hub cog? Or is the cog (sprocket) removed and another sprocket fixed to the wheel?

Trying to figure out your method.

Also, I ran a 28t on a heavily modified china and it would still pull off the line without pedaling. (Heavy, 24" cruiser with lightweight rider.)

Not too many people duplicated my results, though. I think I still have the unofficial top speed record of 54mph, gps'd, with reliable witnesses. 62mph unofficial with catastrophic engine destruction. :)
 

MotoMagz

Well-Known Member
Aug 2, 2010
1,747
929
113
Michigan
When you say "rotates freely in both directions," do you mean with the chain attached to the flipped wheel via the hub cog? Or is the cog (sprocket) removed and another sprocket fixed to the wheel?

Trying to figure out your method.

Also, I ran a 28t on a heavily modified china and it would still pull off the line without pedaling. (Heavy, 24" cruiser with lightweight rider.)

Not too many people duplicated my results, though. I think I still have the unofficial top speed record of 54mph, gps'd, with reliable witnesses. 62mph unofficial with catastrophic engine destruction. :)
 

MotoMagz

Well-Known Member
Aug 2, 2010
1,747
929
113
Michigan
sorry about “
I just don’t feel safe leaving all the inerds in place. Stuff loosens and wears down especially traveling at higher speeds in the opposite direction. Even when I remove a govner I remove everything.If it was a pedal bike ya cut brake arm but I can’t do it on a motorbike.
 

indian22

Well-Known Member
Dec 31, 2014
3,824
4,552
113
Oklahoma
I'm guessing that the reason he wants to flip the wheel is to utilize the stock pedal sprocket as a final drive sprocket for the China girl, which renders the wheel useless for a pedal chain setup. It has relegated the wheel to motor drive only using the pedal cog for that purpose. My concerns about using the wheel in this manner have been noted previously.

I did a wheel flop years ago but bolted a larger sprocket (44t) to the pedal cog and the kids rode it for years, push start & hop on. No pedal chain but kids didn't care...just fun. Brake guts in or out. I'm good with either way. This summer I converted my Simplex with a 125cc 5 speed transmission & wet clutch over to a rear disc brake setup that replaced the coaster brake. The only mod I made to the rear wheel was to cut the coaster brake lever and smooth the cut forming the washer described earlier (no internal work except replace the bearing, repack with grease & adjust the axle for my purposes) I did not flop the wheel so the pedal cog remains active & attached to pedal chain and pedals. No problems to this point after riding these past months, but it greatly improved the rear braking in combination with the front disk brake. The rear wheel turns freely in both directions, neutral or utilizing the clutch I can back it up or go forward; with motor running or not. It just works.

Check my Old Guys Simplex for photos I'll update a couple of photos today or tomorrow. The pedals are active (will rotate) on the stand due to utilizing the bottom bracket axle for both pedal and primary engine to secondary chain drive, but the force of one finger stops any rotation of the pedals. This rotation was present with the coaster brake as well and is due to the rotation of the pedal bracket axle. None of this is noticeable during operation because the feet are on the pedals. Though I have plenty of power, 10 h.p. or so I can pedal assist still & with great effort I can pedal (without engine assist) for a short while, but at 175 lbs. bike wet weight I don't.

One other thing the Simplex now has a 24 t cog on the rear hub, but 5 with speeds I have plenty of torque and have no problems getting off the line.

If one has concerns about any modification I'd suggest doing it your way.Though I've found this to work on multiple projects for years with no problems. Have fun with what you build. This is a great hobby!

Rick C.
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
The pedals can't turn if they aren't attached to the rear wheel via a pedal chain, which is eliminated with this wheel flop. The coasters I've used, in the manner I described in my prior post rotated freely in both directions free of any noticeable internal drag with all internal brake/ hub parts left in place. As I also stated the internals can be removed as well; up to the builder, but I noticed no difference in use, one way or the other. Pedals can be "locked level" and equal since 180 degrees out of phase is no longer required for pedal operation.

As to using the stock Sturmy sprocket with the China kit drive chain. Some old wheel sprockets are a little wider & might be ok for use. Chain & sprockets will wear faster and the chain might try to rub the tire, so a little extra room between tire and chain is a good thing as well. It sounds as though "pitch" is correct between chain and sprocket so all's well in that dimension.

I agree that that the stock China girl motor won't have enough torque to get you moving. Even the highly modified motors have a hard time off the line without the aid of manual pedal assist on flat terrain using 34 or 36 tooth final drive sprockets. Consider it from this point. Count the teeth on the motor sprocket and on the wheel sprocket and divide the two numbers. If the number you come up with is less than 3 you must have active pedals and clutch slip to get you moving. A lot of clutch slip will quickly burn your clutch, but I'm afraid you will really not enjoy riding your BSA as a result of going this direction & that would be a shame as I really like the bike.I also admire your willingness to try something different. .

Rick C.
Thanks mate the bsa is already completed runs sweet.
The new build is a 98cc villiars engine on an old triumph pick bike up today ive got lots of diffrent size sprockets that fit the villiers shaft the triumph will be more of just a veledrome style thanks for the help homework is definetly good for me at this stage the good part about the motor is if all else fails belt drive is a great option clutch wise etc
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
That's a great source Cutis.
I'm glad it's a good runner 'cause it's a handsome ride for sure...fine job & I'm excited about the upcoming Triumph/Villiers build many on this forum have soft spot for these motors. RICK C.
Im glad there so big overseas with a massive following ang great help with all of you...as there fully illegal in new zealand! So for me go big on builds and speed and stick to country roads lol my neighbor is the head of police in our small country town so he lets me carry on the rest may not
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
I'm guessing that the reason he wants to flip the wheel is to utilize the stock pedal sprocket as a final drive sprocket for the China girl, which renders the wheel useless for a pedal chain setup. It has relegated the wheel to motor drive only using the pedal cog for that purpose. My concerns about using the wheel in this manner have been noted previously.

I did a wheel flop years ago but bolted a larger sprocket (44t) to the pedal cog and the kids rode it for years, push start & hop on. No pedal chain but kids didn't care...just fun. Brake guts in or out. I'm good with either way. This summer I converted my Simplex with a 125cc 5 speed transmission & wet clutch over to a rear disc brake setup that replaced the coaster brake. The only mod I made to the rear wheel was to cut the coaster brake lever and smooth the cut forming the washer described earlier (no internal work except replace the bearing, repack with grease & adjust the axle for my purposes) I did not flop the wheel so the pedal cog remains active & attached to pedal chain and pedals. No problems to this point after riding these past months, but it greatly improved the rear braking in combination with the front disk brake. The rear wheel turns freely in both directions, neutral or utilizing the clutch I can back it up or go forward; with motor running or not. It just works.

Check my Old Guys Simplex for photos I'll update a couple of photos today or tomorrow. The pedals are active (will rotate) on the stand due to utilizing the bottom bracket axle for both pedal and primary engine to secondary chain drive, but the force of one finger stops any rotation of the pedals. This rotation was present with the coaster brake as well and is due to the rotation of the pedal bracket axle. None of this is noticeable during operation because the feet are on the pedals. Though I have plenty of power, 10 h.p. or so I can pedal assist still & with great effort I can pedal (without engine assist) for a short while, but at 175 lbs. bike wet weight I don't.

One other thing the Simplex now has a 24 t cog on the rear hub, but 5 with speeds I have plenty of torque and have no problems getting off the line.

If one has concerns about any modification I'd suggest doing it your way.Though I've found this to work on multiple projects for years with no problems. Have fun with what you build. This is a great hobby!

Rick C.
So check out the new frame I just bought.
Handlebars will be changed out to nice chrome ones I have and yes...another BSA either that or a rudge the rims on the rudge were shot though. Heres a quick mock up photo to give you a general idea mate im considering using spacers and bolting engine direct through lower bar and seat post??? Thoughts
20181027_150436.jpg
20181027_150443.jpg
20181027_150454.jpg
20181027_150457.jpg
20181027_150507.jpg
20181027_150513.jpg
20181027_150528.jpg
 

BSAmase

Member
Sep 27, 2018
59
22
8
32
Heres all the sprockets ( which fit the engines shaft and my bikes crankshaft perfectly to give you a tooth count etc the bigger one pictured alone freewheels,
20181027_153959.jpg
20181027_154005.jpg
20181027_153950-01.jpeg
one is a bigger attatched to a small one
 
  • Like
Reactions: indian22

Ludwig II

Well-Known Member
Jul 17, 2012
5,071
641
113
UK
I realise you must face the twin horrors of spending money and buying something modern, but what about doing what I did on my still in progress cyclemotor? Use a 6 bolt disc brake hub and mount the sprocket on that? I used a brake rotor as the intermediary between the 6 bolt hub and the 4 bolt sprocket.


22-8-16 4.jpg