Sturmey-Archer 3-speed tranny

GoldenMotor.com

chainmaker

Well-Known Member
Jan 19, 2010
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Ma USA
Dale, what do you think... One of those right below a jackshaft and flipped so gears are on left side. Jackshaft gear to hub gear hub gear to sprocket on wheel. Think it would work?
 

msrfan

Well-Known Member
Sep 17, 2010
1,808
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Southern California
Dale, what do you think... One of those right below a jackshaft and flipped so gears are on left side. Jackshaft gear to hub gear hub gear to sprocket on wheel. Think it would work?
I think it would do okay if, like the others said, if you have a soft engagement and shift technique. As always, alignment is critical along with your good workmanship, you'll have a working tranny.
 

trackfodder

Member
Sep 8, 2008
347
3
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Don't forget it freewheels in one direction. That is why I used 2 jackshafts.
Someone was enquiring as to my engine. i have given up searching, so if you see this, I am running a HFT Chinese industrial 6-1/2 HP I got on sale for $89.99 I think. They are slopers with OHV and a governor. I really had to work at fitting the origional Jiang Dong 5-1/2 in the Monarch. The seat post had to be moved to the rear fork crotch. The 5-1/2 was getting sticky valves when sitting awhile and got tired of sticking Marvel Mystery in it to stir up a breeze. Tomorrow I am going to de-spoke my Shimano and hunt down a pulley to rivet to it and machine off one spoke flange like the S-A. I may just de-commission the S-A and steal that pulley. It's pretty poor around here now that my water heater shot craps today.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
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northeastern Minnesota
Been gone fishing for Walleye in the Boundary Waters for a few days, so I'm catching up on threads. Is the Shimano pictured a heavier duty unit that the old Sturmey Archer 3 speed hubs from the 1960's and 1970's. Those had a little oiler cup on the hub and as I recall some had the coaster brake and some were free wheel with caliper brakes. Is there an advantage of one over the other in the application of the hub as a kind of gear box?

I'm still trying to get my head around how these would work flipped over as Chainmaker suggests. Seems like they wouldn't would they? I'd like for them to!
SB
 

msrfan

Well-Known Member
Sep 17, 2010
1,808
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Southern California
SB Sounds like a good time fishing. I wish I knew which hubs are heavier duty than others, but I really haven't used one for a powered transmission yet.
 

trackfodder

Member
Sep 8, 2008
347
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I have written an extensive post 3 times, and #1 lost when it said I needed to log in after thanking me for logging in. #2 just disappeared after about 3-4" of writing, The 3rd lost because I stupidly punched POST instead of send or whatever. If you want to know something email me at [email protected] or look up "building a practical and safe motorbike."on SEARCH. It covers this and others. Can't post it again here. The Shimano has a coaster brake and only 3/8" travel on control as opposed to 1/2 for S-A. Can't use the shifter.
 

trackfodder

Member
Sep 8, 2008
347
3
18
I want to KILL something. I just wrote an extensive post and the D---ed thing said I wasn't logged in and lost it after saying thank you for logging in.
ANYHOW: Checked the Shimano. It has coaster brake, and only 3/8" travel. Second thooughts on that one. G Oscar, the Tulsa shp guy did say they were a bit more rugged FWIW. They do freewheel and origionally I was blowing it off as it did the wrog way. A guy online suggested 2 jacshafts and I thought it crazy, but on consideration, went that way. A Bartlesville design uses a rectangle frame for footest and motormount that connects to the seat post and re-shaped downtube following the wheel arc. Handlebars welded to the down-tube form crash bars and give tremendous rigidity to the frame. I welded upright angle irons to the left rear framework with rearward-facing slots for the tranny axle. The shift cable anchors to the rear of it and is threaded through the trampoline spring that tensions the belt. This forum is not user -friendly regarding re-run pix, send your email to [email protected] and will be glad to send details. Also I wrote an essay long ago and presented it here entitled "Building a Practical and Safe Motorbike". It may be available on SEARCH. It covers this project, several others Well, I'll be The lost post is found.:-||
 
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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
I know the feeling and understand how frustrating it is to write out a post, trying to be clear and then reading it over... hitting "send" and either the connection has dropped, cyborgs have intercepted the message and are trying to find hidden messages, or the damned thing has been eaten.... but it is GONE!!! Arrg! And then I no longer have enough brain power to try it again. What I do now when I have a post of any length is to high light it (shows up blue) right click and a menu appears... pick "copy" and left click on that before hitting send. Then if it doesn't go anywhere I can try it again by right clicking and hitting "paste". These computers are wonderful, awful things made for young people.
SB
 

bowljoman

New Member
Aug 7, 2010
370
1
0
Wa
Still, I have my shifter set up where pedal redline is the same as engine redline in every gear.

Hub RPM is definitely important! But also know this: a shift-able jackshaft technically makes your setup illegal.

SickBikeParts gets around that by their product being a single-speed crank assist. Your bicycle has the gears.



You means pedals? I surely do. I don't ride scooters. I'm a Motor-assisted Bicyclist who loves the benefits of pedaling.

They are many.
Actually, any limitations on motorized bicycles and shifting also pertains to SBP does it not? Any allowances for shifting require automatics? So while my foot scooter is illegal for having a top speed that is twice the limit, and being multi speed, to be a motorized bike means less functionality than a moped? A moped is typically limited to automatic shifting too no?

I might get as much exorcize operating a foot scooter as a bike rider, however my engineering skills has made it so I am not required to push off from a dead start. :) Im not foolish enough to attempt to 'assist' my vehicle at 40 mph either. The 64+ inch wheel base makes for a picnic at any speed. I would consider taking my foot scooter to 60 mph without hesitation, and IM looking at strapping a gp460 engine on it, which has twice the torque at only a couple more thousand RPM. So im looking at 52cc currently that gets me to 43 mph@ 6800 rpm, and the upgrade 46CC engine with double the tork, to pop me up to the high 50's at 8400-9100 RPM.

So aside of getting one of those auto shifters, I think SBP is also pushing the law. My goal is high economy, high mileage, with high loadability. While the scooter will push my skinny ass down the road at 43mph, it will also gear down to transport bike-cops/security officers with gear up the hills in our downtown corridor. The price of these vehicles with all new components and suspension one-at-a-time is under 1000 bucks and logevity is proven beyond 2000 miles. In a batch of ten, the motor mount drops to half the price, saving another 175$

I love making things!

I love shifters!

I'd have made a bike if I had found a frame that I liked.