engine size?

rwquiring · Oct 23, 2015

I have decided to start a new project on an old 50's era Monark, and I would like to know what the size of the frame needs to be to fit a 4 stroke motor in it.
Or what the overall size of the motor is so I can make a template and see if it would fit. Thank you

Royce

2door · Oct 23, 2015

Royce,
We would need to know what 4 stroke engine you're planning on installing. They aren't all the same size. Some of the small 49cc engines are close to the same size as the Chinese 2 strokes and some, like the Predator are huge. It makes a difference when considering a frame.

Tom

rwquiring · Oct 23, 2015

Thanks Tom for replying,

I think that I want to go with one of the Chinese 4 stroke units that most of the vendors are selling here, I did see that on one of the YouTube vids that I saw there was a guy that had a piece of card board that was cut to 8 inches wide by 9 1/2 inches tall, but I just want to make sure before I "pull the trigger" Thank you for your help.

Royce

rwquiring · Oct 24, 2015

Does this look about right? the size of the wood is 8 wide x 9 1/2 tall.

KCvale · Oct 27, 2015

rwquiring said:
Does this look about right? the size of the wood is 8 wide x 9 1/2 tall.

Even a little 4-stroke is going to be close...
You have to start your measurement from a level spot just above your pedal sprocket and your wood isn't there.

From there you need 10.5" up in the back, a bit less in the front.
Depending on your exhaust you still need a good 10" of base plate length.

There are things you can do depending on the engine, like offsetting the carb or cutting the choke lever down, but not ideal.

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engine size?

rwquiring

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