2-speed systems (R-D, dog-clutch or derailleur changing)

Thud said:
I havn't tore down the 3 speed shimano e-bay hub I picked up yet, but I am thinking it would be realitivly easy to mod the unit for a double freewheel & still fit standard frame spacing.
Click to expand...
Thud,

Did you see that we're hoping to get these made: http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=12449&start=223 ? In conjunction with the SRAM Dual-Drive hub, they will make a plug & play 3 spd/7 spd system.
 
Ha! yes, I apologize for teasing with a rare part. 3-speeds are so cheap and robust now, someone might be able to buy up the F&S stock cheap (I can't imagine many people wanting one), but there probably aren't that many left. I would be annoyed to hear about a new "perfect" prototype system that relied on an obsolete part that was unavailable for purchase...

When I was originally discussing 2-speeds, and someone pointed me to the F&P, I was mostly interested in a proof-of-concept prototype. Once somebody actually makes something and posts real-world performance, a system with improved characteristics can be copied and improved (And possibly scaled up or down for other applications). Tesla was concieved with a 2-speed, but production delays made it a single).

I am very interested in your work because you are actually building the prototype of one of my favorite ideas. The economic downturn two years ago cut deeply into my prototype-building, and now all my ideas are only on paper.

There is a market for an Ebike 2/3-speed. However, I am firmly convinced that the biggest market for a custom shop-built 2-speed is for E-motorcycles. I have seen several builds that attached a motor to the stock transmission to gain its benefits, but they only used 2 or 3 of the gears, and the trans used up a lot of valuable battery space (plus, it involved lots of un-neccessary shifting). Also, getting acceptable accelleration from a smaller motor means better range and lower purchase price, plus easier packaging.

Right now you can get great E-moto acceleration and top speed from a big motor and 108V of lithium. But thats expensive, and I don't expect the price to come down much anytime soon.
 
Miles said:
Did you see that we're hoping to get these made: viewtopic.php?f=28&t=12449&start=223 ? In conjunction with the SRAM Dual-Drive hub, they will make a plug & play 3 spd/7 spd system.
Click to expand...
Miles,

I have been following that thread with interest. It will provide a lot of flexability.
I am curiouse, what is the major Diameter of the casett carreir? & are they standardized?
(It apears you did not have to remove much thread to slip it over)
all I have on hand are 5 & 6 speed freewheel stacks from salvaged bicycles.
I should post this in that thread I suppose.

I have had a local EDM shop do some delicate internal cutting for me in the past.(recutting internal lands for the dogs to engage on vintage motorcycle transmisions-hardend gears)

Also, reading through the link, it seems the "Auto's" are sold out from that location, but can be found on the auction sites. (I would love to have one in hand to evaluate) the "auto" was the only one that grabbed my interest.
 
Thud said:
I am curiouse, what is the major Diameter of the casett carreir? & are they standardized?
(It apears you did not have to remove much thread to slip it over)
all I have on hand are 5 & 6 speed freewheel stacks from salvaged bicycles.
I should post this in that thread I suppose.
Click to expand...

I milled the threads of my freewheel down to give an I.D. of 34.4mm, so that it just slips on the cassette driver of the SRAM hub. The driver on the SRAM is slightly undersized compared with some other drivers but they all the same nominal size. Minor diameter of the standard freewheel thread is 34mm so yes, not a lot to remove to get clearance. Not much there if you want to cut spline slots into it, either........ Using the removal tool recesses on the freewheel to lock it to the driver worked fine.

The 9 spline cassette driver isn't a published standard. Most other makers have just copied Shimano's specification, more or less. Campagnolo have their own splined driver, which is different.
 
Spin,
You posted during my reply to Miles, Lunch break also?
I bought a E-motorcycle conversion package from Cloud electric last year for a motorcycle build. A Lot happend in the family that side tracked the project. (weddings & death...life happens)
I never considerd anything but a 2-speed (or posibly 3) for that project.
I have the patterns made to cast a gearbox to bolt onto the Mars 708 pancake motor. & 56AH @ 48V of AGM batteries to power the thing. Add a bunch of junked Suzuki TS125's as the doner bikes.
The lil' tranny is a scaled down version of it.
As far as prototyping goes its been a part of my lively hood. I made my living doing one-off's for the yacht & furniture industry here in west Mi. for years. Currently doing design engineering for a custom manufacturer of architechual & library stuffs mostly.
I need to resurect the "good" home computer & make some 3D models to show on the web in hopes someone will plagerize it & produce someting I can just "buy" (it would save a lot of time :lol: ) I really have no interest in "manufacturing" runs of anything. I get my kicks designing, make 1, then handing off.
 
Interesting, I once spent a winter at the Navy base Just north of Chicago (1977) and I couldn't help but to notice the sub-zero weather seemed to encourage indoor hobbies...keep everyone posted, this is good stuff!
 
Here is last nights effort.
observations: louder than I hoped.
seems to shift just fine.
my efforts to quiet it will be next
#1 use a softer material for the slipper chain guide & refine the geometry
#2 dump the ball bearing guids on the shifting fork. they howl durring a shift & at rest if the get any pressure on them, This will entail polishing the hub groove & going to a solid brass end on the fork.
other than that I have all the tourqe need .
Here is a look for those who hate text. Please ignore the heavy midwestern accent. :D
[youtube]7El6_T20YZM[/youtube]
time to mount it up & get to some e-biking!
I have to work now....
 
Would something like this work?

https://www.surpluscenter.com/item.asp?UID=2009101516531297&item=1-2950&catname=
 
http://www.schlumpf.ch/uni_engl.htm

This isn't an RD, Dog-clutch or derauilleur tranny, but it is a two speed hub that could be
used as a transmission. I'm guessing that there is no freewheel either...
so it's probably fixed like the S3X only two speed...

Schlumpf is a planetary gear nut, so it makes sense that he would build a 2 speed
unicycle hub. It has square crank mounts for just about any crank....which
would make it relatively easy to adapt chain rings and freewheels to..
Push button shifter, just like the cranks..

Ratios
1.5 and 1:1

Price, yikes...! ~$1000...

His speed and mountain drives are ~ half that price.

(edit: There is probably a dog-clutch or similar that is activated/deactivated by the push button that either unlocks/locks the planetary)..
 

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Ironic that this tread was bumped as I signed on to do that very thing. naw I will start a new thread.
 
Thud said:
Here is last nights effort.
observations: louder than I hoped.
seems to shift just fine.
my efforts to quiet it will be next
#1 use a softer material for the slipper chain guide & refine the geometry
#2 dump the ball bearing guids on the shifting fork. they howl durring a shift & at rest if the get any pressure on them, This will entail polishing the hub groove & going to a solid brass end on the fork.
other than that I have all the tourqe need .
Here is a look for those who hate text. Please ignore the heavy midwetern accent. :D
[youtube]7El6_T20YZM[/youtube]
time to mount it up & get to some e-biking!
I have to work now....
Click to expand...


I had missed seeing this video. WOW! What a smooth operating tranny :) Extremely good work Thud! Contrary to what most people think, dogs shift so nicely, it's like every shift is butter as long as your pull the lever quickly.
 
A very simple power shift gear.

The zero shift gear:
http://www.zeroshift.com/
http://www.zeroshift.com/pdf/SPORT%20COMPACT%20CAR%20ARTICLE%2012-12-05.pdf
http://www.zeroshift.com/transmission-technology/animation.html
 
Don't know how I missed this one as I was following it closely back then. Very nice werq on the trans and a very smooth shift with no load. I appreciate the time you spend with the explanations and videos as you go about your build. It's a bit of werq I know but helps many of us, in more way than you can imagine, as we plan our own projects. Thanks for the latest and the rest.
 
Thanks guy's, did you see the completed unit?
http://endless-sphere.com/forums/viewtopic.php?f=28&t=13731
scroll to the bottom of the page.
 
Dauntless said:
That's fantastic. I have to pursue making one of those. Anything besides this thread you think I should read up on?
Click to expand...

See here for Thuds 2-speed drawings: http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=7832&start=30#p309846

Hey Thud, what was the recent edit to that post?


Jay
 
I swaped out the original pdf with the newer version that has better center to center distances for the uniform chain tension between the 2 ratio's.
its a true 1-1 in high gear now & 1.86-1 in low.

I pulled the original pdf during the comercialzation of the forum....(not that its not out there already) its well coverd by the creative commons agreement if if anyone wants to conform to that idealistic document. :p
 
Ah, I see. Thanks for the clarification.

I am hoping to achieve equal center to center distances for uniform chain tension between the 2 ratio's for my drive as well. ;) :D

Jay
 
found this link might be of interest
http://www.troeger-engineering.de/content/lexikon/Allgemeines_ueber_Getriebe.pdf
 
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