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single carb on 3 cylinder motor-need advice

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ive been working on frankenx (my 3 cylinder 3 wheeled 2 stroke wondermutt) lately and after tinkering with the wiring i figured out the problem and it now has spark and i have gotten it to run, although it did so like crap. it has good compression and good spark, but on tearing apart the carbs i have come to learn that they are pretty well toast. in favor of a simpler system i have opted to go with a single carb system. i have already talked to a machinist friend of mine who is going to fab me up an intake for a good price, and i have already lined up a cr500 carb. my question to you anyone here who knows 2 strokes is this: what problems could i come across by attempting to run 3 cylinders off of 1 carburetor? i know it sounds stupid but i really cant figure how multi cylinder 2 strokes get an equal amount of gas to each cylinder (look at a lot of the 2 cylinder snowmobiles), so naturally i cant see how each of the 3 cylinders would get their equal share of gas. anyone here want to flex their head muscles a little and give me a little lesson of the subject?

thanks guys, Doz.

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you're setting yourself up for one hell of a bad experience.. you'll be dealing with issues like unequal intake lengths,and the corresponding air mass issues.. and unless each manifold has it's own reed system, you will get double mixing from intake blow back... you will have trouble with the center cylinder wanting more fuel because it runs hotter thanks to it's position.. twins get by cuz their duty cycles are much more separate than triples and the big one... you can be placed halfway between a twins cylinders.. you can't be equal distances from each hole on a triple. save your machining money, sell your CR500 carb and get three old school vm mikunis and you'll be much happier

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you NEED to have 3 carbs on that engine! You refer to twin cylinder sleds only having one carb. Have you ever heard of a triple with one carb? Nope, cause there's no such thing! WHY? cause it doesnt work! You will will have one very rich cyl., and two very lean ones.

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Yep...the guys are all correct. But tell us a bit about the motor. What is it? Whats done to it? Is it a piston port or reed valve motor? You can buy triple banks of carbs all the time off snowmobiles on ebay for less than $100.00. I would definetely go that route. But tell us about themotor and I'll give you a good idea of what you want for carbs.

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it appears to be piston port (i cant find any reeds), it is 371cc's-from the mid 1970's, aircooled, in line 3 cylinder, 2 stroke, came from the suzuki assembly line without expansion chambers (the exhausts were just like those on 4 strokes), is 6 speed, 54mm x 54mm stroke/bore, 6.7:1 compression, chain drive, and is kickstart only. its a suzuki gt380 motor.

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it appears to be piston port (i cant find any reeds), it is 371cc's-from the mid 1970's, aircooled, in line 3 cylinder, 2 stroke, came from the suzuki assembly line without expansion chambers (the exhausts were just like those on 4 strokes), is 6 speed, 54mm x 54mm stroke/bore, 6.7:1 compression, chain drive, and is kickstart only. its a suzuki gt380 motor.

A bank of carbs from a GT380 would be a good place to start...

I had a friend that had a GT380 back in JR. High that he had stripped everything off of and used it as a trail bike, I am very lucky to be hear after riding that, those motors scream. :thumbsup:

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