banshee seems lazy after rebuild

[CaNaDa_NS]

ok this is my buddy's banshee. here's what he did he put in a hot rods stroker crank, bored .60, it's got k&n, jetting i'm pretty sure 240 main, boost bottle, fmf gnarly pipes bike works good other than it's lazy bottom end till the powerband cuts in. it starts perfect and idles amazing before he put the stroker crank in it worked good bottom end. just wondering if that the nature of a stroker crank?

[gregrob]

ok this is my buddy's banshee. here's what he did he put in a hot rods stroker crank, bored .60, it's got k&n, jetting i'm pretty sure 240 main, boost bottle, fmf gnarly pipes bike works good other than it's lazy bottom end till the powerband cuts in. it starts perfect and idles amazing before he put the stroker crank in it worked good bottom end. just wondering if that the nature of a stroker crank?

 

 

No, that's opposite the nature of a stroker crank.

 

240 sounds extremely lean to me on a 4mil. My stock stroke was at 270mains all the way at 6000ft elevation. I had T-5's and pod filters.

 

He needs to get the jetting right. Do a plug chop and get that main jet where it needs to be.

 

Then he probably needs to work on the pilot jet. The wrong size pilot will make it doggy on the bottom.

 

That and check the compression and squish clearance. If the compression will low it will be lazy and if the squish band is way too high it will too, as well as having lower compression than it should.

 

If it's hard to start, that's your first clue the pilot jetting is off. And if that main is as lean as I think it is it's not getting any fuel to have any torque.

[CaNaDa_NS]

the bike ain't hard to start it starts very easy first kick everytime. ok i also forgot to mention that we are at sea level and less than 1000ft. he was thinking pilot jet.

 

 

No, that's opposite the nature of a stroker crank.

 

240 sounds extremely lean to me on a 4mil. My stock stroke was at 270mains all the way at 6000ft elevation. I had T-5's and pod filters.

 

He needs to get the jetting right. Do a plug chop and get that main jet where it needs to be.

 

Then he probably needs to work on the pilot jet. The wrong size pilot will make it doggy on the bottom.

 

That and check the compression and squish clearance. If the compression will low it will be lazy and if the squish band is way too high it will too, as well as having lower compression than it should.

 

If it's hard to start, that's your first clue the pilot jetting is off. And if that main is as lean as I think it is it's not getting any fuel to have any torque.

 

[gregrob]

That main jet is too lean at sea level unless he has a very very lazy signal on the carbs.

 

What size carbs, stock?

[CaNaDa_NS]

That main jet is too lean at sea level unless he has a very very lazy signal on the carbs.

 

What size carbs, stock?

 

 

yup carbs are stock. what size should he have? and where do ya get them?

[RZBansheeMan]

You said that he put a "stroker" crank in it ???

 

What about the porting ?, when putting a stroker crank in a 2 stroke, they need the ports reworked to match the added stroke. Port timings are critical on a 2 stroke and if that is what he did, it is not going to run right.

[TurningRPMS]

Lol way to lean on the main

 

Start wiht a 340 and work your way down.

and a 30 for the pilot.

Maybe a 27.5 will work. try them .

[vulvafan537240]

im at 500ft asl and i run 290 mains and 30 pilots. 240s are super lean. that motor wont last long like that.

[pr0blumz]

Yeah, its too lean....try a 280. A guy I know put pods on his bike and didn't re-jet and it sounds like a starter pistol everytime he try to launch it. I told him it was too lean and he said "Nah, dude told me it's because I changed the sprocket on it." :sad: