Two Speed Automatic Transmission

GoldenMotor.com

curtisfox

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Dec 29, 2008
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Hi Curt. I just recently received a shipment from Staton and it did take a little longer than I expected, but it was complete and in good shape.
Yes they are now saying a refund is coming through, Dave has always been good to me, but has been years ago. I have faith, but some don’t have any patients to wait.
so how are you doing? I have been busy with other things instead of bikes, except to snoop and buy a couple. Helping my son on redoing his house, not the place for a old man, but keeps me going. LOL............Curt
 
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Forbidden Tuna

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Sep 3, 2019
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Sorry to post in this old thread but I remember watching a video from the AGK guys showing their 2 speed auto jackshaft. It's weird though because the high speed uses a standard centrifugal clutch. I guess for this setup it depends more on wheel speed than engine speed and once locked in will overcome the 1 way bearing.


He's using a SBP one way with the shaft adapter and the Max Torque double sprocket primary clutch.
 

Tony01

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The video above is the standard setup. You need an engine driven clutch and a freewheel for first gear, and a jack shaft driven clutch for second gear. So two clutches and freewheel.

The problem with those dual sprocket clutches is they won’t fit two heavy duty gold chains side by side. If you need the beef you can run a single sprocket hard mounted to crankshaft for 2nd gear and use primary clutch for 1st gear only. I haven’t messed with 2-speeds for a while but I have a design I have wanted to try for years now. Would be one belt in, one chain out, and only one clutch and freewheel... figure that one out!!
 
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Tony01

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I actually really like the sound of that to be honest. I think it could prevent wearing out the 2nd gear clutch because you could let it loose as soon as you're ready.
Actually the first gear clutch is what wears fastest because it is seeing higher rpm and heat. But using a dual sprocket first gear clutch means the 2nd gear is also dependent on it, it needs both clutches to be locked. The better method is having one clutch per gear therefore the 2nd gear sprocket solid mounted on crank (because 2nd gear clutch is jackshaft driven). Problem is lack of crank space.

Also chains wear unevenly, the important chain is the top gear so you have to design your system for a slightly looser 1st gear chain when top gear has proper tension. Agk used a half link in one of the chains which in my experience will break. There’s a lot of small design problems including the fact that chains don’t like to go fast, so any chain transmission setup off the motor is doomed essentially as far as reliability.
 
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curtisfox

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That is probably why the took them off the market LOL. There has been a few guys that built manual belt drive 2 speeds, but not auto. But like msrfan said to get them to fit, even using better clutches would take up more room. I have a Honda express that has a auto 2 speed that run in oil, am going to investigate, to see how it works, just maybe..............Like to see one more reliable..............Curt
 

Tony01

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Tony's right about the longevity of the chains. The clutch bells wear very fast also. I working on a totally belt driven 2 speed but I don't know if I can shrink it down enough to fit on a bike. Trying to cut down on maintenance.
 
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