Dual 44 Mikuni observations

[Mark44]

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your lows are to small and your highs are to big
your pop is to high causing the fuel to start flowing later. lower your pop off to about 20 psi put a 125 low in it and 115 high

Dont just put a bigger low in it and say it didnt work
you need to reverse jet it correctly and these things hit hard

Trust Waxhead.

Mark44

 

[Legdragger]

Ok I can do that.

 

[Legdragger]

Does anyone know if the stock manifold has a crossover tube I should plug on my stock 760?

 

[sjetrider]

these OEM 44 or SBN 44's MAkes a HUGE diff..

 

[sjetrider]

just going back for some reading. You mistook what I was saying here. If running dual carbs the coupler in center can get loose and not keep carb plates in sink and in a hard landing you gas to take off and the carb will suck the slave carb butterfly closed tempararily. Always check the couplers between carbs.

 

[Matt_E]

Yup, I just had that happen. The coupler I'd been using for three years had worn out to the point of allowing about 5-10 degrees of movement

 

[Freakrider]

and a bad carb coupler will make it idle higher, sound lean or run away out of the water...

 

[Mark44]

R

just going back for some reading. You mistook what I was saying here. If running dual carbs the coupler in center can get loose and not keep carb plates in sink and in a hard landing you gas to take off and the carb will suck the slave carb butterfly closed tempararily. Always check the couplers between carbs.

Good item to check every year. Thanks!

 

[Legdragger]

I have OEM carbs. What's the big deal? I wanted to get these figured out before I put on a sset of 46 full spectrums i have had on the shelf.

 

[waxhead]

I have had great results with the oem carbs. Some people dont recommend them that's fine that's up to them.
All 760 carbs are 2nd hand and so it makes them hard to sell new carbs Im not sure this is why other people dont recommend them.

Personally I can get a cleaner hit out of the stock oem 760 carbs than the aftermarket ones. you just have to jet them right and they will suprise you.
Also they have the best linkages out there and are so easy to adjust

 

[Smokin'FX-1]

Figured I would throw in my very limited experience. My wife's ski is 760 with ported cases, widened exhaust ports on cyl, 38cc domes, etc etc. We were running stock 38's until last week (it was all we had). I had heard/read we would only get a minor increase on the low end other than increased fuel consumption. Swapping to the stock 44's gave it a very noticeable hit increase all around, especially down low, and made the throttle response crisper. Also fuel consumption when playing around seems close to the same so far.

I'm only posting this because some people may be in the boat we were in. Luckily I trusted my motor guy and got the 44's.

 

[Freakrider]

Figured I would throw in my very limited experience. My wife's ski is 760 with ported cases, widened exhaust ports on cyl, 38cc domes, etc etc. We were running stock 38's until last week (it was all we had). I had heard/read we would only get a minor increase on the low end other than increased fuel consumption. Swapping to the stock 44's gave it a very noticeable hit increase all around, especially down low, and made the throttle response crisper. Also fuel consumption when playing around seems close to the same so far.

I'm only posting this because some people may be in the boat we were in. Luckily I trusted my motor guy and got the 44's.

I agree with this...44's RIP when a motor/pipe are ported and other mods are done...

 

[waxhead]

Man they were just getting cheap again on ebay

 

[Legdragger]

Running the 125/115 20psi in my 760. Goes better but still feels numb up top. I heard about a 120/100 combo that a guys swears rips so I am going to drop my main some more and see if it gets stronger. Throttle respons is getting there now though.

 

[Smokin'FX-1]

Kind of funny. The 760 we put the 44's on is running 120p/100m, 2.3 n/s, 80 spring, 2t on L, 1/2t on High. Only had them on for a little over a week, but it seems great.

I haven't done much tuning on the H side so it could probably use another 1/4 turn, maybe.

 

[Legdragger]

Ok I am going leaner, 120/100.

 

[waxhead]

115 is way to rich, try the 100 with what you have it will be very close as

 

[Legdragger]

125/100 feels the best yet. Need to get a set of 120's for the pilots. Although it is getting pretty brappy as it is.

 

[kevbo]

I have been playing with OEM 44s lately and have found them to need a fairly rich part throttle mixture for best response. I had to tune the top screw 60+ rpm rich of peak whenever part throttle was lean enough to prevent excessive fourcycling. This tune gave best overall range and safest full throttle operation. An overly rich part throttle mixture combined with peak rpm provided the hardest hit but burned more fuel and is less safe for long full throttle runs. The OEMs tend to run leaner at part throttle than aftermarket 44s for a given pilot/popoff setting.

 

[waxhead]

the leaner running down low is due to them having one less progression port, Like you suggested a lower pop off is all thats needed to make it right. I have not had an issue with them up top. I always reverse jet my carbs to get good hit through the mid range, But yes your right reverse jetting will use more gas but you got to feed the ponies.