Single carb vs dual
- Thread starter Lil Dick
- Start date
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
Were tuning a x2 right now. It had keihen 38s on it that came with the motor. We didn't have the stuff to tune it. We put a single 44 on it. We have tried every imaginable combination of jetting and we can't get the power out of it that we had out of the 38s.
- Location
- South Africa
You will need a 48
- Location
- Ontario, Canada
I ran duals on my cheater pipe, then ran a single SBN44 and found that the single was a bit stronger bottom end. But I wasn't sure if that was the way to go so I bought a pair of R&D Prolock flame arrestors and for the 38s, changed from choke to primer and found that the duals woke up quite nicely. I then bought a Speedwerx pipe and tried both set-ups, liked them both but went with the duals because they were the last set-up installed and I just wasn't in the mood to change out again. This year I am going to be running a 48 single and see how I like it. I do really like that the tuning of the single is fast and easy, I found that the duals never really wanted to dial in 100%, always fooling around with the mixture screws trying to get that really nice tune out of it.
- Location
- Cruising Around
Ran a lot of combinations on my Blasters and am very happy with the single 48 on one and single XSR46 on wifes, but they are just for cruising . On a hard hitting standup on a budget its hard to beat a pair of 46's. If you can afford it 48's or 49's
- Location
- Ontario, Canada
I found that the only loss I had was with prolonged top end when running the 44. It would hold a solid top end but only for about a minute or two tops then it would struggle to supply enough fuel. The 48 shouldn't have that issue. I remember reading an old post from Matt_E saying that the use of a single carb with an intake spacer is a bottom end set-up whereas a dual 38 without the spacer is more top end oriented. I also remember that at the time, the poster asked about an intake spacer with dual carbs and Matt_E said that it was basically a counteractive effort since the duals were meant to achieve what the intake spacer was not meant for. I could be wrong, it has been a very long time since I read that posting but I did remember him saying that much, it always stayed with me when I bounced between my SBN44 and the duals, and if a spacer would make duals better.
Tyrant1919
Site Supporter
- Location
- Washington, DC
If you aren't good at tuning two carbs, get a single. A well tuned single will outperform whatever duals you have on. But in the end, Duals > Single.
- Location
- Ontario, Canada
^^ It's true, you do need to know how to set up duals before ever playing with them. But they will always be finicky anyway just because the carb kits are never going to be made identically matched from the same batches of material unless you get them direct from the manufacturer of each part. The metering diaphragms are always the first to start changing in integrity. One might be stiffer than the other due to the material being produced that day, one might soften quicker than the other, one might be affected by different flavors of fuel compared to the other. There are loads of variables not including metering diaphragms that require a lot of time to get the best out of duals, and each year they will require re-tuning until they get to a point of degradation where you are tuning every ride. I just don't like investing that kind of time if I am not making a career out of it...I prefer quick and easy tuning with loads of ride time rather than loads of launch tuning and limited ride time. It's all relative though and just personal preference =)
- Location
- Colorado
It's all about finding the right combination it might be duals or might be a single. But once you do find it don't touch a thing. That's my 2 cents
waxhead
wannabe backflipper
- Location
- gold coast
A single will save you a heap on gas, Duals will put a larger smile on your dial
- Location
- fortcollins
Singles generally make more snap out of the hole, a single will actually get worse millage than 38 twins, I've never had an issue on wot runs with my 46 single and I'm a touch over a full limited setup with advaced timing, Some boats like singles some like twins some like triples
waxhead
wannabe backflipper
- Location
- gold coast
A well tuned single beats a badly tuned set of 38s hands down every time.
The 38s have a larger volume in a pair than a single 46 does. if your using the 650 kawasaki manifold with the adaptor plate then it has less flow in its runners than a stock 46 and thus is the choking point. It makes it very hard to jet in and also very unstable in the jetting as well
The 38s have a larger volume in a pair than a single 46 does. if your using the 650 kawasaki manifold with the adaptor plate then it has less flow in its runners than a stock 46 and thus is the choking point. It makes it very hard to jet in and also very unstable in the jetting as well
Duals u will all ways have more hit but after that there the same
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- Location
- Amherst NH
But both 38's arent feeding a single cylinder together. Each 38 is feeding a single cylinder.
- Location
- Amherst NH
I dissagree
- Location
- Amherst NH
I dissagree