High performance Carb stops when engaged!!

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I'm at just over a mile hi. Here it takes a #66 jet to get it running without constant 4 stroking. At sea level the stock jet should be good. I'm not really sure what you mean by bucking. If it is just at slow speeds that is normal. The engines don't have much power at low rpm. It looks like everything is brand new. What ratio are you mixing the gas/oil? It will also begin running better as it breaks in.
There are varying opinions on these carbs. I haven't noticed any improvement over the stock nt or speed carbs. other than less chance of the float sticking. Original Dellorto carb. is a diff. story, but you pay dearly for it.
 
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Ratio for fueling is 8oz of oil to every 1 gallon of fuel till 4 gallons have been burnt off; then 4oz to every 1 gallon in perpetuity.
 
Don't get too whacked out over the carb, I've seen these work, and other just behaving as a paperweight for no known reason at all. Like straight out dead from factory. A simple mistake like forgetting to drill a hole in the cast could totally throw off a carburetor. Even other microscopic flaws (cracked cast or a bubble trapped in the wrong place) can just make it impossible to properly tune one in. It just happens and since there's little to no chance that they hook these up to motors and test them before they leave the factory then there just has to be a few defects around.

I've had units just refuse to run a motor at all, swap it out for an identical (brand and settings) carb and it starts right up. The only explanation is that the carb is junked. Some spots on a carb can be very difficult and even impossible to reach with a cleaner unless you physically removed plugs from the cast to access the little side ports that do the magic.

My current carb uses 2 jets, and the idle jet has its flow of fuel go in the idle jet but has a small hole that takes it off to the side where it meets the idle air mixture screw and pathway for the fuel to the intake. If somehow that would get clogged or be left with flakes of cast in it it would not hold an idle, and I can see cleaning that particular path in the carb as being difficult because of the location/shape.

Yeah uh... If you can faithfully eliminate all the other problems then look at the possibility that the carb is physically imperfect to the point where it can't perform the job is meant for.
 
By bucking I meant The engine sputters and still no major power. May be a throttle adjustment. I'm of course still keeping it under 20k for 20min. intervals. Engine cools, then I go again for another 20min. but still a little logy on power. By the way thanks gary55 for your help. Appreciated.
 
Good advice Franken, I will consider those imperfections. As of now it seems to be working within normal perimeters. The choke lever was opposite on this Run Tong clone. Not much dialog about this design nor did it come with a working schematic. So I had to figure it out from this forum.
I will educate...
 
I think the lack of Quality control in the manufacturing of these carbs. is spot on. Since the nt's have a little more options for adjustment and more simplicity in design they are less intolerant. The 8 oz. per gallon recommended by the manufacturer is excessive. What I see here on the forum commonly accepted is 6 oz. first gallon 4 oz. after. Part of your loss of power is to much oil. Clean the plug and try it with 6 ozs. and I think you will see a difference.
 
Ah yes, this forum still edjoomacates me every day, I enjoy it.

That choke on the carb is definitely my favorite by far. The choke is on the entire pull except for the very end, then it just pops off with a flick of the wrist.

Would be cool to implement one of those "click off" mechanics on one of these Cns carbs that some people love and others hate with great passion.
 
Yep. Racin. I built a NASCAR themed bike and its fast...
But it wont make right turns. :scratchhead
 
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