Is it safe to say smaller carbs are easier to tune?

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Chicago Ben
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Is it safe to say smaller carbs are easier to tune?

Post by Chicago Ben »

I'm trying to resurrect my build that has just been sitting doing nothing

I have an af16e that trafficjamz whipped up for me with a boost port matched ruima 50mm bbk, stock crank and some ruima secondary gears etc.

I originally had an OKO carb that had a goofy float - so I picked up a 28mm Keihin Carb Clone off ebay that leaks everywhere- the drain screw is virtually cemented in.

I have a "PG Typhoon" Pipe -- you guys think an Oko 21mm carb would be "easier" to fine tune than a larger say.. 28mm/30mm carb?
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1995 SA50P
pop pulley
50mm Ruima
8.44:1 gears
PG Typhoon
1500k spring
1000k Polini triples
M Keli clutch
28mm Keihin PWK
OKO Polished intake
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patthesoundguy
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Re: Is it safe to say smaller carbs are easier to tune?

Post by patthesoundguy »

I think the idea is to have the correct carb size to match the setup. Carbs that are way too large will never ever tune right. The trick is to have a carb large enough to take advantage of your bbk but no larger. So I think a smaller carb will be easier to tune but if it's too small your performance can suffer just like it will suffer and be impossible to tune if its too large. What are others running on the at size kit and having good results is where I'd start

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LMH
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Re: Is it safe to say smaller carbs are easier to tune?

Post by LMH »

patthesoundguy wrote:I think the idea is to have the correct carb size to match the setup. Carbs that are way too large will never ever tune right. The trick is to have a carb large enough to take advantage of your bbk but no larger. So I think a smaller carb will be easier to tune but if it's too small your performance can suffer just like it will suffer and be impossible to tune if its too large. What are others running on the at size kit and having good results is where I'd start

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Wheelman-111
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Re: Is it safe to say smaller carbs are easier to tune?

Post by Wheelman-111 »

Greetings:

TreatLand sent me a 28 when I had ordered another 26. I decided to keep it and see if I could get it to work. It certainly doesn't seem to go any faster than the 26, and it isn't as clean in the low-midrange. Go as small as will give you the top end you need. The Ruima might be fine with a 24, unless ported to rev to the moon.
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Chicago Ben
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Re: Is it safe to say smaller carbs are easier to tune?

Post by Chicago Ben »

thanks guys - appreciate it - I was never able to get my moped tuned quite correctly. With that said I really would like to get this setup running just so it is reliable. You guys think a 24mm oko will do justice here?

I had a trailtech spark plug thermocouple temp gauge but it died...
Image
1995 SA50P
pop pulley
50mm Ruima
8.44:1 gears
PG Typhoon
1500k spring
1000k Polini triples
M Keli clutch
28mm Keihin PWK
OKO Polished intake
uni filter
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