Super Jet 701 dual carb tuning issues

[mike b]

Friend and I are tuning his 701 square with dual carbs. Motor and all is from raider701. Put a stock superjet exhaust on engine and it fired right up. Would idle nice but once you would give it gas it would bog and want to die or even die sometimes..Too Rich?
Started tuning the low adjustments to lean out the engine but same problem. So i went to adjustment for low speed again but richened it a bit more than how it came out of the waveraider but it wanted to rev a bit so shut it down before it ran away or something. Came out the waveraider with 6/8 for low speed which i thought was close to what the superjet dual 701 usually runs. Any ideas on why its not running right. Ive done this swap before and i just leaned the motor to 5/8 on low speed and worked fine. Btw motor worked great in waveraider and carbs are bringing in fuel. already checked diaphram and thats in good shape too so i know it is getting enough gas into the motor

 

[Tyrant1919]

"So i went to adjustment for low speed again but richened it a bit more than how it came out of the waveraider but it wanted to rev a bit so shut it down before it ran away or something."

Sounds like it wants more gas. It wouldn't rev on you all of a sudden when you richen it unless it wants more gas.

 

[River Rat]

Did you change the jets? There diff size on both carbs I know you said u've done this before but u didn't mention that u switched the jets .?

 

[mike b]

Have not changed the jets. But before when i had done this swap i changed the low adjustment from 1 1/8 down to 5/8. Same exact jet ski and motor set up and is already at 6/8.

 

[mike b]

it idles nicely when i have the low leaned out. just whenever i give it any throttle it bogs. Wouldn't that mean too much fuel? and that it is being flooded, or just that there is not enough fuel to meet its needs

 

[550headache]

pop off too high

 

[mike b]

pop off too high

but why would this one give me trouble and my other set up didn't give me problems like that?

 

[Vumad]

A 701 62t/61x with stock 38s and stock pipe has 1.5 n&s 115 gr spring 53 pop 130 main 70 pilot. Screws are like 1.5 bottom and like 1.5 top front 2.0 top rear (those screws setting are a little off)

Wave raider is 62t/62t different port time might be slightly different jetting. Popoff of 50 is fine on stock carbs and airbox but a little lower is good if possible.

Can't say for sure I'm no pro but test the carbs. If you don't have a gauge get one, worth the money.

 

[mike b]

A 701 62t/61x with stock 38s and stock pipe has 1.5 n&s 115 gr spring 53 pop 130 main 70 pilot. Screws are like 1.5 bottom and like 1.5 top front 2.0 top rear (those screws setting are a little off)

Wave raider is 62t/62t different port time might be slightly different jetting. Popoff of 50 is fine on stock carbs and airbox but a little lower is good if possible.

Can't say for sure I'm no pro but test the carbs. If you don't have a gauge get one, worth the money.

yeah im heading off for school today so this project will probably wait for winter break unless my buddy does work on his own but i know it will just get stored till next time im back. Ill resurrect this thread then if were still having problems

 

[Vumad]

yeah im heading off for school today so this project will probably wait for winter break unless my buddy does work on his own but i know it will just get stored till next time im back. Ill resurrect this thread then if were still having problems

I'm having problems with mine too. I'm just taking it to one of the local mechanics when my new pipe shows in the mail. Don't have time to mess with it even though I know it is simple. I know Jesse will have it apart, back together and tuned before I would even get a chance to touch it.

I bought parts from the local yamaha dealer and wasn't paying much attention. The parts were not OEM they were SBT. I didn't think anything of it until I couldn't get my carbs to work right. I had issues checking the popoff with leaking fuel pump and etc. That's when I realized SBT is a problem. I put the factory O-rings back in and no more leaking. I guess lots of people have good luck with SBT but I am not one of those people. My buddy with a HX with SBN 38s was also having problems and put his factory N&S back in and got better results than with brand new SBT parts.

Bottom line is that SBT N&S and rebuild kits are not accurate/reliable enough to count on. I'm sure that is part of my current problem. I haven't tried the WSM parts yet but have a few I will try soon because I got them for very cheap. Buying genuine mikuni parts only will help a lot with carp problems. Willing to give WSM one shot too but not optimistic.