modifying a two stroke to run in reverse

[justin86]

I am planning on a project kart, dead axle with a motor driving each wheel (2 motors), so I am going to need one to be running in reverse.
Has anyone done this? and how did you do it?

I can't just use a live axle, as this is a replica and if I change to live axle then it wouldn't be a replica.

Regards Justin

Here is a picture of a similar kart to my one.

 

[modelengineer]

If it's a piston ported or reed valve 2-stroke then I believe all you need to do is change the timing and the recoil starter to spin it the other way.

If it's a front rotary valve, rear rotary valve, or drum valve (all pretty unlikely) then it will be a lot more work.

 

[Russ2251]

What model engines do you intend to modify?
Need to engineer a reversed flywheel...for 2 reasons, at least.
Good luck

 

[justin86]

I want to use the masport 8/02 series lawnmower with the iron horse motor.

How would I modify the flywheel? I am a little new to these motors, I am comming from model nitro motors, cars, and bikes.
I have to mod the flywheel because of the timing right?

 

[Angus]

Hmm... this might be a pretty noob thing to ask, but why do you need to make the motor run in reverse? Couldn't you just make one of the axles long enough to reach through to the correct side of the motor?

Perhaps this would introduce handling issues that I'm not away of...

 

[Russ2251]

What you have, essentially, are Lawn-Boy model D engines. Both are points ignition which complicates things further.
Flywheel has to to be completely re-engineered to run in reverse for timing as well as correction to magnetic poles. South-North would have to be North-South.
Recoil would also be a problem.

 

[sideways]

What you have, essentially, are Lawn-Boy model D engines. Both are points ignition which complicates things further.
Flywheel has to to be completely re-engineered to run in reverse for timing as well as correction to magnetic poles. South-North would have to be North-South.
Recoil would also be a problem.

Also, the flywheel would now be sucking air instead of blowing it.

As for the magnet, just hook a coil off a car up to the points, that solves that problem. You'l need a battery though.

Thanks

Hayden

 

[Russ2251]

the flywheel would now be sucking air instead of blowing it.

Statement is incorrect. Fins are straight and not curved.

 

[sideways]

Statement is incorrect. Fins are straight and not curved.

Ah, my bad sorry.

Hayden

 

[fowler]

iv gotta agree with angus it seams like u are going though a lot of trouble
when u could just make an axil on one side

EDIT* unless u want to use 2 one wheel drive wheels and dont want to use bearings

 

[Russ2251]

To my knowledge, these are the only folks that currently make CW and CCW engines.
http://www.usmotorpower.com/820.htm
Would be cheaper in the long run to get 2 of these.

 

[fowler]

honda does i think
or at least did
im sure i read something somewhere i just cant find it

 

[Kenny_McCormic]

Have you considered constructing a very simple reverse gearbox?

 

[fowler]

well done kenny
dam it took a while to work that out

 

[justin86]

Thanks for the replies guys, makes for a lot of thought and further study. I have a friend who is a small engine mechanic and a car mechanic, might get his help on this too. I am a student engineer, and I like to do things that people just don't understand why I did it the way I did it lol
Anyway I am after a certain look about the motors, that is important to me.
As for using a coil from a car, couldn't I use power from the normal motor? to supply the both? sorry I have worked on many types of motors even a 27 nash, but electrics I can't seem to get.

 

[justin86]

Just thinking about what russ has said, and looking over some small engine manuals, maybe I could have the motors both hooked up to a descret jack-shaft, with direct drive no clutch.
think I need to do some pondering.

 

[Kenny_McCormic]

Have you considered a hidden live axle?

 

[devino246]

reverse gearbox would be the simplest, easiest, and cheapest IMO. It wouldnt be that big so it wouldnt change the look much.