Anyone tried one of these

James1968

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Aug 2, 2018
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The stock 13mm NT carb is not big enough to properly feed a 66cc engine. At a red line of 7000rpm or less 15 to 16mm is perfect size.
 

cannonball2

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Oct 28, 2010
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I have one if the 15mm Bing slide clone moped performance carbs. Havent tried it as I need to order a 40mm intake. You have to make a sleeve to make the intake fit and adapt an air filter. As I remember it was around $20.
 

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cannonball2

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I have been running one of those on a Flying Horse for several years now. Its a decent carb. Was way rich as received. Remote choke is nice as is an idle circuit.
I tried the 12mm version of the Bing figuring I would loose some top end but gain better response and low/mid range. Was just too small. The 15mm may be just right. I have since swapped my CGs to pumper carbs so this one may never happen.
 

Citi-sporter

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Jun 16, 2014
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I have been running one of those on a Flying Horse for several years now. Its a decent carb. Was way rich as received. Remote choke is nice as is an idle circuit.
I tried the 12mm version of the Bing figuring I would loose some top end but gain better response and low/mid range. Was just too small. The 15mm may be just right. I have since swapped my CGs to pumper carbs so this one may never happen.
I'm trying out the VM12 on my first CG engined bike with a Amazon bought Kaxton 48cc. Since the smaller engine should be similar to the 50 cc Yamaha kids bike in fuel draw and metering.

Your old thread inspired this build. Pumper carbs are a nice idea but since I'm using the stock tank I figure I don't have to plumb for manifold or crankcase pressure taps.

Although I've got this broken down old Tillotson carb off a 60cc Homelite cut-off saw and I'm thinking of cutting the old carb to liberate out the pumper half, to make a 1 gallon remote tank fuel pumper, if I don't like the range of the little peanut fuel tank.
 
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cannonball2

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Tillotsons are great carbs. You can pull a pulse from the intake if the carb is not already plumbed that way. I discovered by accident that the Still carbs will run by gravity feed. I thought the pulse passage in the carb was drilled, but it wasn't. Ran fine until the tank got on the low side. The total adjustability of a pumper saves a lot of jet work.

The best running slide carb I have is an NT with a much modified slide. A bunch is removed from the bottom to lean the first 1\3(lowers the needle). Runs super clean. Down side must warm up completely to idle. The carb you linked is a good choice, the adjustable idle circuit is great. It was also used on a 50cc moped a Yamahopper I think.
 
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javy mcdees

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eventually took a brass hammer to my NT carb even as it was running good but the slide stopped sliding in the bore and nnothing fixed it until the bras hammer fixed it, now have a runtong after 3 carbs got one good one.
 

cannonball2

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I have tried the Runtong, not much of a fan. Neither am I of the NT. Was just determined to make one work. Get something with an adjustable idle circuit what ever it is.
Jaguar at the other forum has some fixes for the Runtong.
I like the idea of adjusting the NT with a hammer!
 
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javy mcdees

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I have tried the Runtong, not much of a fan. Neither am I of the NT. Was just determined to make one work. Get something with an adjustable idle circuit what ever it is.
Jaguar at the other forum has some fixes for the Runtong.
I like the idea of adjusting the NT with a hammer!
NT had the best low end power, but the runtong is a close contender now after some jetting. For sure the runtong has better mid and top end hands down. The NT carb must of warped the body from the heat and stopped working the slide, the brass hammer made sure of body had no slide. Runtong runs good but wont idle which is fine for me. But wonder how a real Dellorto would run over the runtong. Or any of these carbs listed in this thread.
 

Citi-sporter

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I'm expecting that the little PeeWee Yamaha clone carb, being smaller in the venturi area than the stock NT carb, will have a drop in top-end performance with the CG 48 cc engine. Frankly I'm OK with this, as I'm looking to get a smoother low RPM range and more torque down low as this bike will be towing a Bob trailer.

Smaller in venturi area means a faster draw of air through the venturi at smaller throttle openings which should improve the fuel air mixture at lower RPMs.

Cannonball2 posted a thread back in 2014 about experimenting with alternative carburetors, and had highlighted the VM12 as being easily modded. Mine only needed a strip of 16 gauge soft aluminum sheet to adapt to the alloy intake spigot.

I will have to customize the stock CG throttle cable and make a enrichment circuit control with a friction shifter, Having owned a number of small Yamaha and Suzuki enduros in the 1970's having a thumb control for the choke is nostalgic.