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Miss firing right cylinder


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Well best thing would be make or buy a leak down tester. Here is a link on ebay http://www.ebay.com/itm/Yamaha-Banshee-Two-Stroke-2-Stroke-Leak-Down-Tester-/291786994849?hash=item43efdc34a1:g:PtMAAOSwYmZXHX2A&vxp=mtr

otherwise with out it you'll be just going in circles.

 

Okay sweet thanks man.

Cuz ive triple checked and made sure it isnt the:

Carbs

Soark plug wires,

Spark plugs,

Carb boots,

Carb slides (adjusted perfect),

I checked fuel lines,

Looked thru every hole or passage way in the carbs,

I unhooked the tors and tryed pluging it back in,

I would say it could be exhaust but it backfires to so that cant be it,

Ive looked at the reeds they look goofd from wat i can see,

 

The right cylinder (the one that runs like shit) runs closest to the left cylinder (the one that runs fine) at very low rpms and very hight rpms (almost full throttle,

But thru the WHOLE mid range

its like The cylinder that runs good is blowing and ba dingin (lol) 5 times stronger then the weak one and the good one smokes alot more to,

 

Time to get a leak down tester i guess .

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And both cylinders are at 117 psi,

Bone stock shee,

 

Im not sure in this i just want to ask but if i did have a leak wouldent the cylinder thats leaking run more lean and higher rpm, thats wat ive exsperinced in the past.

The cylinder that running bad on mine is just running weak (less ummff)

 

45 bucks aint bad though ima prolly just get the leak down tester so i have it to.

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While you had the carbys apart did you look at the nozzle # 13 in the link https://www.rockymountainatvmc.com/oem-schematic/0that along with your needle in the slide control fuel in the mid range. but all this will be thrown out of whack if a gasket or seal is leaking air into the motor. would create a lean condition-more air then fuel.

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that lean condition will be right through out the rev range & could cause that cylinder to run weak, pull the plugs & post a pic of left & right plugs. take note of the color or if dry or wet. a plugs appearance can tell you a lot about how an engine is running.

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that lean condition will be right through out the rev range & could cause that cylinder to run weak, pull the plugs & post a pic of left & right plugs. take note of the color or if dry or wet. a plugs appearance can tell you a lot about how an engine is running.

 

Okay i hear wat ur sayin,

And the plugs are a nucce coffe brown. But the one the is running bad is allways a little weter,

Thats wat made me think it eaither not burning off the fuel or its geting to much fuel.

Thanks for ur help man.

 

You guys in here have helped save my ass a few times

Edited by Yamahafan#1
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Could be 2 reasons i can think of why the plug is wet,

flooding carby, incorrect settings/jetting, etc. this has all been ruled out with your work already been done.

The other possibility is if your right crank seal is leaking, it could get transmission oil in to your engine which could leave the plug wet.

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Could be 2 reasons i can think of why the plug is wet,

flooding carby, incorrect settings/jetting, etc. this has all been ruled out with your work already been done.

The other possibility is if your right crank seal is leaking, it could get transmission oil in to your engine which could leave the plug wet.

 

I did recently change my clutch plates and shift shaft and installed a pancake bearing.

I did leav it apart for awile clutch cover off for about(3,4 weeks)

Wonder if it is the crank seal!,

 

 

Do i have to take the exhaust off to do the leak down test with that exact tester off ebay?

Edited by Yamahafan#1
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The only way to find out if it is the seal is the leak down test & regardless of the tester used, the exhaust has to be removed & the ports plugged off.

Yup! Im in the process of ordering it now. And i didnt mean to say take exhaust off i ment to say motor out of frame my bad, and i couldnt see why i would have to do that.

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LOL all good & no you don't have to take the motor out of the frame.

 

I figured,

And when amd if it dose come to change the crank seal i can pop the seal out right?, cuz on my 250 i can just screw a screw into the seal and pull it right out. Ive never dine it on a banshee but i figure its the same shit. Just all the videos im finding the cranks out the motor.

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