Author Topic: 4 stroke carb vs 2 stroke carb  (Read 1243 times)

strkablaz

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4 stroke carb vs 2 stroke carb
« on: December 04, 2007, 05:56:54 PM »
Can you run a 4 stroke carb on a 2 stroke engine?  If not, why?

Moskito

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4 stroke carb vs 2 stroke carb
« Reply #1 on: December 04, 2007, 07:41:03 PM »
What carb are you looking at?

Most four stroke carbs (at least the newer units) have an acceleration pump built in - that won't work on a two banger.  Instant flooding.  Trying to put an FCR carb on a two stroke will be a lesson in aggravation.

The jetting will be off.
Four stroke specific carbs often have a more sensitive low end circuit or circuits.  They feed the engine half the amount as a two stroke carb and they deal with a larger vacuum signal from the engine.

It can be done, though, but it's a pain in the butt.

I used to run a two stroke carb on an old XR500 - what a mess that was...
Moskito - Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming \'WOW-What a Ride!\'

strkablaz

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4 stroke carb vs 2 stroke carb
« Reply #2 on: December 04, 2007, 07:56:10 PM »
Thanks for the in put.    I knew their was a reason why nobody did it I just couldn't figure out why.