4 stroke mounting

Taffy13

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Sep 23, 2019
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So I know most 4 stroke engines run clockwise when looking at there face ( pull start side ) meaning that you have to put the face on the drive side of the bike ( towards the pedals ) and run the chain down the left side or through a jackshaft but what if you use a set of gears to reverse the direction so you could have the output on the drive side of the bike?
Making it able to fit slant piston engines( 79, 189, 212+) easier by moving the piston to the other side away from the seat tube.
 

curtisfox

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Dec 29, 2008
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Takes 2 jack shafts, one regular and second to run sprocket on the outside of the first to reverse direction.........Curt
 

Taffy13

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Sep 23, 2019
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Lol yea I'm not talking sprockets I'm talking cogs curt and when 2 cogs are in mesh they spin opposite ways

So my thought was, have two cogs, one connected to a clutch, and the other spinning a sprocket. In basically a small case filled slightly with gear oil. And boom no need for a jackshaft just go from output sprocket to your chain rings. And if you need rpm reduction just use 3:1 gears in it
 
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waynesdata

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Lol yea I'm not talking sprockets I'm talking cogs curt and when 2 cogs are in mesh they spin opposite ways

So my thought was, have two cogs, one connected to a clutch, and the other spinning a sprocket. In basically a small case filled slightly with gear oil. And boom no need for a jackshaft just go from output sprocket to your chain rings. And if you need rpm reduction just use 3:1 gears in it

I like the idea. You would have to draw it up and look for things. Will all moving parts be away from the rider? How will the new setup change final ratio? Will it make since in terms of cost?
 

Taffy13

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Sep 23, 2019
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I like the idea. You would have to draw it up and look for things. Will all moving parts be away from the rider? How will the new setup change final ratio? Will it make since in terms of cost?
Well all moving parts would be encased and bathed in oil so shouldn't be any hazard to the rider, and that's an interesting point because 1:1 wouldn't affect final ration, but it could be a quick swap case so someone would choose any drive and driven gear and have any kind of final drive ratio so say they need an overdrive because they have a super torquey motor they could do a 1.5:1 drive another example could be you have a high rpm engine with poor low end you could do a 1:2 ratio as a torque converter.
Now for cost to manufacture that's an interesting one but using what I've already layed out all you would need is a case, let's say cast aluminum. 2 bearings 1 for each gear, shafts for the gears to key to. And that's about it. With a quick change gear system you could offer any number of gears and different materials for different applications.
 

curtisfox

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Dec 29, 2008
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Lol yea I'm not talking sprockets I'm talking cogs curt and when 2 cogs are in mesh they spin opposite ways

So my thought was, have two cogs, one connected to a clutch, and the other spinning a sprocket. In basically a small case filled slightly with gear oil. And boom no need for a jackshaft just go from output sprocket to your chain rings. And if you need rpm reduction just use 3:1 gears in it
Then you are talking about seals and all, it ends up doing the same thing as pulleys and sprockets, only more compact, a little more drag with oil and seals LOL. Also see it done with cogs in the open like sprockets........Curt
 

Taffy13

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Sep 23, 2019
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well sorta it would be compact, wouldnt need any adjusments and you could run the engine with the output shaft on the drive side of the bike so really only 2 chains needed for a shifter setup. also instead of the cylinder facing the seat tube it would face twards the front wjeel leaving alot more room for bigger engines