dual 44s on 701
- Thread starter fastgtfairlane
- Start date
waxhead
wannabe backflipper
- Location
- gold coast
The 4 progression ports flow more fuel at partial throttle. I would run the 125 low, but I never run anything but oem 740 44s, they are too much of a bargain.
Plus the oem linkage etc awesome
You could remove the plug and drill the hole in them if you want to get it right. Its an emission thing after all and who needs that
Plus the oem linkage etc awesome
You could remove the plug and drill the hole in them if you want to get it right. Its an emission thing after all and who needs that
waxhead
wannabe backflipper
- Location
- gold coast
My upgrade carb list goes like this
stock 38(yuck)
760 oem carbs ( smiles all round and a great gain if tuned correctly)
46 mikunis, worlds best kept secret ( if your buying bigger carbs why would you stop at 44s)
48 novis ( welcome to the real world)
stock 38(yuck)
760 oem carbs ( smiles all round and a great gain if tuned correctly)
46 mikunis, worlds best kept secret ( if your buying bigger carbs why would you stop at 44s)
48 novis ( welcome to the real world)
waxhead
wannabe backflipper
- Location
- gold coast
What oil ratio do you run on the oem versus the am lol
waxhead
wannabe backflipper
- Location
- gold coast
I wish most of you guys came to the word finials, having this convo at kokomos would be fun
waxhead
wannabe backflipper
- Location
- gold coast
Old school
I’m currently running a set of 4 holes on a SJ with TNT, good domes,and reeds. 130/110 or 125/115. About the same
without good head and reeds. 125/115
32:1 maxima 927 in everything including weed whip
4 holes is what is sold by mikuni. 4 holes are what are in all the dual kits from last 25+ years. Only in last 5-10 years have people started to use the oem Yamaha 760 sets In numbers.
WaveDemon
Not Dead - Notable Member
- Location
- Hell, Florida
The "oem mikuni" thing is a little tricky because in this thread people are taking about the mikuni 44sbn carbs that Yamaha sold oem on the 760's. People also sometimes say 'oem mikuni' to mean mikuni carbs straight from mikuni as opposed to mikuni carbs that have been modified by Novi, Full Spec, etc.
Adding even more complication to this Yamaha sold sbn44's as single carbs with a few variations. The "Yamaha oem 44's" that came on the 760's (which we are referring to as oem 44's in this thread' are different than the mikuni 44sbn's that you would but straight from mikuni (which we've been calling "4 hole" in this thread) and the Yamaha oem single carb from the 701 and the Yamaha single carb from the 650 and probably some other flavors of sbn44 that might have been sold as oem in other skis are all slightly different in ways that are sometimes hard to identify.
I say all of that because the set of 44's that you have in that pic don't look too me like they are "oem 44's" from a 760 that we have been talking about on this thread. Which of the other various flavors of 44sbn they might be I have no idea.
To answer your question I personally would use the 44s, my reason would be I don't know anything about this modified 46's and I'd be worried that they might have tuning quirks that I don't want to deal with. If I was feeling adventurous I might try out the modified carbs but I'd be going into it with the expectation that it might not work out.
But that's me being cautious. Other people in this thread would probably have a better answer.
To be honest what I would do and have done is get a whole carb and intake assembly from a 760. As Wax pointed out they have a nice linkage and a kind of "speed plate" that makes tuning a little more convenient than those old fashioned intake manifold that you have to unbolt the carb from the manifold to change jets.
I couldn't tell you anything about how the performance compares though.
I couldn't tell you anything about how the performance compares though.
waxhead
wannabe backflipper
- Location
- gold coast
there is no oem 46 well not tat you can get to easily there was a single carb on a wetjet
I see no reason to run a carb with out a bombsite.
The reason you take the bombsite out is to make the carb flow better. simply move up to the next size carb. When you take the bombsite out it makes them harder to tune. the bombsite is a actually a signal booster
Interested in hearing what @waxhead or anybody else thinks about this:
Often repeated conventional wisdom is that you want to get your pilot jet size so that your low speed screw is one turn out.
But
The low speed screw on a 64x carb has not only much finer thread, but also a shallower angle on the needle. This picture is compared to an sbn46 low speed needle.
So really the equivalent in a 64x carb would be something way more than 1 turn out. Probably three or four.
I'm planning on tinkering with it too see if I can tell any difference, but... Thoughts?
Often repeated conventional wisdom is that you want to get your pilot jet size so that your low speed screw is one turn out.
But
The low speed screw on a 64x carb has not only much finer thread, but also a shallower angle on the needle. This picture is compared to an sbn46 low speed needle.
So really the equivalent in a 64x carb would be something way more than 1 turn out. Probably three or four.
I'm planning on tinkering with it too see if I can tell any difference, but... Thoughts?
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waxhead
wannabe backflipper
- Location
- gold coast
Yes your right on that one, the oem 44 that theory does not work, I am happy to about 2 turns out and then I start thinking I can run a bigger low and pick up more torque
- Location
- Charlotte, NC
very interesting on the screws. i rode with a guy sunday that has a b1 with a 61x/62t setup with dual 44s. i think he was running a 115p, 135m, 2.0 n/s 95g spring on his. he was having low rpm bogs and opening the screw out 1 turn made a big difference for him.
bored&stroked
Urban redneck
- Location
- AZ
Seadoo used dual 46's on the 946 motor as well. No idea if those work on Yami's or not.
If I wanted bigger carbs the biggest I'd go is the oem dual 44's from Yamaha until I got into aftermarket engines. Once you get some real power going dual 46's would be my choice until you need the big boy aftermarkets.