Carby Keihin carb clone

I get to my top speed faster and I have found back pressure helps when you're at top speed I can adjust my muffler well iam going and if iam doing 65kmh when closing the muffler I can get 67 68. This is a different muffler but the flap in side is the same. Open shut
 

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i have found that this carb works best without reed valve box i just got a simple form hose at the auto store runs great idles 2800 top speed 32
 
Didnt have to rejet my issue was withing the bad spark plug gap and the long exhaust is more for torqe then speed if you want speedngetting a short like the speed demon exhaust for speed from what a few people have told me im also looking into possibly porting the piston on the intake to match port on intake of jug
 
Oh and im running 4 1/2 onces oil to 1 gallon gas 32/1 basically i just add extra half once oil

My math tells me you are running 28:1 oil. TOO MUCH. Kills the plug and performance.
Use no more than 32:1 or 4 oz per gallon.

I am running 57 kph with a well scratched cylinder and a stock NT carb.
What is this carb gaining you?

You have to walk before you can fly. Get the stock setup working before modifying anything.
The guys who have truly experimented have discovered 32:1 is the richest oil mixture that works.
Another half ounce is not better. It fouls the plug and interferes with the burn.

So how was the performance with the stock carb? What has this one gained?

Steve
 
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My math tells me you are running 28:1 oil. TOO MUCH. Kills the plug and performance.
Use no more than 32:1 or 4 oz per gallon.

I am running 57 kph with a well scratched cylinder and a stock NT carb.
What is this carb gaining you?

You have to walk before you can fly. Get the stock setup working before modifying anything.
The guys who have truly experimented have discovered 32:1 is the richest oil mixture that works.
Another half ounce is not better. It fouls the plug and interferes with the burn.

So how was the performance with the stock carb? What has this one gained?

Steve


some people are gluttons for punishment, masochistic, and dont learn.

nice solidly mounted carb...that thing looks like a cocktail shaker! frothy fuel, air in the jet...aint never gunna run well.

boost bottles...waste of time and money on these things.

keeping the stock exhaust, whilst expecting the carb to make massive gains, which it wont.

whats the bore on the carb? looks like a 20, 22 even... bit pointless, feeding that into a 16-17mm port.

four or five changes in intake diameter, due to the rubber hose and the spigots used, each and every one adding its own bit of turbulence.

no consideration of intake length and how that affects things.

a bad situation all round.

so, i shall ask the same thing...what gains has this carb achieved over the stock NT? other than serious headaches?
 
some people are gluttons for punishment, masochistic, and dont learn.

nice solidly mounted carb...that thing looks like a cocktail shaker! frothy fuel, air in the jet...aint never gunna run well.

boost bottles...waste of time and money on these things.

keeping the stock exhaust, whilst expecting the carb to make massive gains, which it wont.

whats the bore on the carb? looks like a 20, 22 even... bit pointless, feeding that into a 16-17mm port.

four or five changes in intake diameter, due to the rubber hose and the spigots used, each and every one adding its own bit of turbulence.

no consideration of intake length and how that affects things.

a bad situation all round.

so, i shall ask the same thing...what gains has this carb achieved over the stock NT? other than serious headaches?

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The carb is actually a 19 mm. My engine came set up for the carb with cheap reed valve. They opened the exhaust port and cleaned the transfer ports and opened the intake port a little bit and put a vertical grove about and inch wide below intake port and half inch up and wide above intake port. I matched everything after reed valve for less turbulence, I haven't run it since matching everything after reed valve tho.
Has anyone seen or done this kinda of port work on the intake and what purpose dose this have. What's good or bad about it.
 
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