Is It worth 2 into 1 Carb?

[M3Bamshee]

I want to go for 2 into one carb kit, but not sure if it is safe to do so or if it will cause problems with fuel delivery to two intakes. What would you more experiance guys recon.

[bigboybanshee]

LOL, I have one for sale if you want to try! :biggrin:

 

Here's my take on it. If you have a bolt on banshee with simple stuff, the setup is great. Once you start putting some heavier mods on it, it just isn't enough fuel.

 

I have been battling with my 2 into 1 carb setup for a long time. I have the trinity setup with a 38mm Keihin PJ carb. I put it on there, it fires right up. As soon as I punch the throttle, it takes off like a scalded dog to 3rd gear then falls on it's face, chokes and dies. Have to come to a stop, pull the choke, and kick it 10 times to get the bike started again. Take off again, same thing. I wasn't sure if it was happening because I didn't have a big enough main (plugs were white), or if the bowl was running dry. I started off with adding a powerjet and it helped, the bike ran stronger but it still cut out and died by 3rd gear. I put my dual stock carbs back on there, problem solved, but the bike didn't run as fast. Here recently I put a pair of 34 PJ's on there and it runs like a bat out of hell now :smile:

 

I just figured I'd share my experience, and help others make a decision before forking out several hundred dollars on a setup that may not be enough for your mods.

 

On my trail bike I run:

RDZ ported stock cylinders

Trinity Head, running 165psi, on 110

Paul Turner mids

Timing at +6

Ported stock reed cages, boyeson two stage reeds

 

The 2 into 1 just wasn't enough...I was sucking the bowl dry :shrug:

 

:beer:

[Fireroad Express]

Snopcynzki(sp) posted up a dyno sheet on this about a week ago. do a search or scroll down and you should find it.

[Snopczynski]

Do a search next time.

2 into 1 dyno tests link.

 

As for as mods go, its not true about it not being enough fuel. My bike has porting done and a 35mm pwk is almost too big for it. It was showing signs on the dyno that indicated a 34mm pwk would have been the best way to go. However, they dont make one, and the pj is crap. We also run three 4 mill strokers on 2 into 1 intakes, and we run a 460cc 7mill cheetah motor off the 2 into 1 intake. 2 of the strokers run lectrons, and the other two run pwk 35's. I would bet if the bowl was running dry, the float level was not set correctly, or your fuel line was not big enough.

Edited February 11, 2008 by Snopczynski

[IrideA250R]

I want to go for 2 into one carb kit, but not sure if it is safe to do so or if it will cause problems with fuel delivery to two intakes. What would you more experiance guys recon.

 

I wouldn't bother, stick with twin carbs.

[sheerider1026]

i have a 2 into 1 also. ported motor, 19cc domes +5 timing, vforce reeds, t5 pipes. its the 35mm pwk and it screams, no problems at all. the trick is also haveing the right needle in the carb. there is a lot of tuning that can be done, not just swapping out the main jets.

[bigboybanshee]

Glad to hear you guys are having great luck with yours, mine was running out of fuel. Changing the needle might have helped, but I don't think it could have been that drastic of a change to keep my engine from running out of gas. Float height was correct, i went through the carb several times. It's just not enough fuel for some setups, each one is different. I am now a firm believer that 2 cylinders should definitely have 2 carbs. Just my opinion though.

[IrideA250R]

there is a reason modern, high performance snowmobile 2 stroke engines have a carb for each cylinder, because it aids the performance of the engine.

[lonestar]

When I had mine, Harry from trinity built mine himself. Stage 2 porting with he's stage IV pipes & 35pwk. His stage iv head 19cc domes. With wiseco pro lites. He set everything up himself. I shipped the motor to them. They got the motor in 6 days. He called me ask me what type of ridding i plan on doing. I told him a fun bike all round type ridding. I'll set you up with my best selling kit. I'll be doing the porting. I got the motor back in the frame in 18 days. This Fu---- bike flew. This bike was like a ROCKET. I went through 4 bore's with this motor I still have the bottom end. Keeping it for a spare tranny for the motor I have now. This motor got me what I have today. I was bitten. Who ever say's that the 2into1 don't rev & don't rev on top this motor DID.

[Snopczynski]

Modern snowmobile motors are designed and clutched to maintain absolute peak rpm ALL the time. You dont wick the throttle on a sled like on a quad.

[jmd0346]

Glad to hear you guys are having great luck with yours, mine was running out of fuel. Changing the needle might have helped, but I don't think it could have been that drastic of a change to keep my engine from running out of gas. Float height was correct, i went through the carb several times. It's just not enough fuel for some setups, each one is different. I am now a firm believer that 2 cylinders should definitely have 2 carbs. Just my opinion though.

 

 

Only one cylinder is pulling fuel at one time. I have a hard time believing a 38mm carb cant supply a 175cc cylinder. Your bowls were running dry. As snop said from too small a fuel line or float height too low. How can you say the floats were set "right". What is right? Right is however high or low they need to be to provide proper fuel. Ive had the exact same problem on my 30mm carbs. Raised their height a bit and problem solved.

 

 

 

Ive had a couple buds with 2 into 1 and they both went back to duals. They always had problems getting them tuned. We tried everything with them. They had stock jugs though and I think the 35mm 2 into 1 is too big for stock cylinders. We went lean as hell on the jets and it would still blow smoke like a diesel. Threw on the stock duals and it ran perfect.

[sheerider1026]

i have stock cylinders, you had the wrong needle in it, i had the same problem with my 2 into 1 setup. i tried everything and almost gave up, the snop told me to change the needle, so i tried it and dam it runs like a dream now.

[Snopczynski]

i have stock cylinders, you had the wrong needle in it, i had the same problem with my 2 into 1 setup. i tried everything and almost gave up, the snop told me to change the needle, so i tried it and dam it runs like a dream now.

 

Yeah, most of the time they run on the needle, the wrong one can make the mid-top power really bland and hesitant.

[bigboybanshee]

Only one cylinder is pulling fuel at one time. I have a hard time believing a 38mm carb cant supply a 175cc cylinder. Your bowls were running dry. As snop said from too small a fuel line or float height too low. How can you say the floats were set "right". What is right? Right is however high or low they need to be to provide proper fuel. Ive had the exact same problem on my 30mm carbs. Raised their height a bit and problem solved.

 

 

 

Ive had a couple buds with 2 into 1 and they both went back to duals. They always had problems getting them tuned. We tried everything with them. They had stock jugs though and I think the 35mm 2 into 1 is too big for stock cylinders. We went lean as hell on the jets and it would still blow smoke like a diesel. Threw on the stock duals and it ran perfect.

 

When I say it was set "right", means I set it to the height that keihin recommends you set your float for that carb. That didn't work, so I went higher to see if it helped, but guess what, it didn't help, I went to the point of it overflowing out the back of the carb.

 

What was the purpose of you quoting me and re-iterating exactly what I said was the problem? The bowl ran dry, I'm aware of that. I ran 5/16" fuel line, and the float height was set correctly. You guys are trying to play me off as a retard, I know how to jet and tune a carburetor. 1 carburetor is not enough fuel for some setups, plain and simple. Get it through your skull that not all banshees are the same, they're all tuned a little differently, in different climates and altitudes. Just because the 2 into 1 carb works for you, doesn't mean it's going to work on everyone else's setups ::

[Snopczynski]

Your supposed to set the float level different with the 2 into 1 intake cause it sits at a different angle then when used with regular intakes. Like I said, there should not be anything different with your setup that made it so that carb would not work. We run a 38mm carb on a 460cc 7mill cheetah motor. It doesn't run the bowl dry. From what your decribing, sounds like something was probably broken or missing in the carb if it was smoking badly and "blowing" smoke.