Traded for Banshee and runs terrible

[FROSTBITE1]

Hi im new here, two weekends ago i traded a 2007 400ex for a 2003 Banshee. When i test drove it seemed fine but i didnt open it up to much because of confined space at the dealership. Anyway this weekend i was toolin around the back of the company where i work and i notices it hesitates before it gets in the powerband but once its up there it moves very well. I ordered some jets to tune it better but they havt gotton here yet and i took the banshee out to the dunes and it was a gut less wonder out there i couldnt even get the rpms up to get past the hesitation into the powerband. I did a compression check and i kicked a 115 on both cylinders which i know is a tad low. Some help to point me into the right direction, right now im thinkin its because where i got the bike the elevation is 4982 ft and where i ride is 3000.

[Idontknowwhy]

Compression is still alright,

what mods?

[FROSTBITE1]

TORS is gone, FMF gold series pipes in Toomey silencers...one leaks out of the back of the silencer. A single KN airfilter. Thats all i know of.

[Idontknowwhy]

crack them carbs open see what jets are in em

[Screaming Yellow Zonker]

pop your plugs out and see what they look like. that would be the best way to know the fuel condition. also pull the choke one notch while riding and see if it reacts better.

[FROSTBITE1]

Ok i tore into it this morning here is what all i found, Plugs-light tan. Pulled the exhuast off both where leaking very bad from missing half and o ring on the flange where they mount to the cylinders and both where also leaking from cracks by where they are mounted to the frame and both silencers are leaking out the back. I pulled the air box off and filter and found an outwear crumpled up in the neck of the air box just before it splits into the carbs. Pulled a carb off and found it has 260 mains with a 28 pilot.

[TwistedSheeRida]

dam thats a big pilot jet. you should be able to use a 25 with that setup

[fastbanshee8]

FMF pipes like a 27.5 pilot jet. Your main seems too small for pipes, and a K&N. Try a 280, or 290 main. Where are the air mixture screws set at? Both should be about 1.5 turns out.

[TwistedSheeRida]

FMF pipes like a 27.5 pilot jet. Your main seems too small for pipes, and a K&N. Try a 280, or 290 main. Where are the air mixture screws set at? Both should be about 1.5 turns out.

 

i run the fmf sst and mine wouldnt even run when i put in the 27 im running the 25. guess bikes are diff

[vulvafan537240]

260 mains may be good with the airbox still on. i run 290's with pods. the pilots cant be 28's. they only come in 2.5 increments, 25, 27.5, 30 etc.

 

do a plug chop or WOT plug check and see what the plugs look like.

[FROSTBITE1]

Well musta mis read it looked like 28 stamped on it. Ill look again. Anway here is what i got planned im trashing the exhuast system... its just in crappy shape. I got a set of DMC aliens and silencers ordered. I also order two K&N filters that directly mount to the carbs. DMC recommends i start with a 30 pilot jet and at least a 320 main jet when not using a air filter lid. Im gonna see what jets i get in the mail and go from there tomarrow

 

260 mains may be good with the airbox still on. i run 290's with pods. the pilots cant be 28's. they only come in 2.5 increments, 25, 27.5, 30 etc.

 

do a plug chop or WOT plug check and see what the plugs look like.

[AKheathen]

get some pics of the carbs, and the pipes, while you are @ it

[FROSTBITE1]

well i got carbs apart and replaced the 260 main and 25 pilot with a 340 and 30 pilot. Im doing to run two direct carb mounted kn filters and a DMC alien system when it gets here.

SIDE NOTE i noticed it has aftermarket idle screws on them ( on the sides of the carbs) , idk how to ajust them but from what i read on the internet if there not right the banshee doesnt run right?

[stringbeanbowler]

well i got carbs apart and replaced the 260 main and 25 pilot with a 340 and 30 pilot. Im doing to run two direct carb mounted kn filters and a DMC alien system when it gets here.

SIDE NOTE i noticed it has aftermarket idle screws on them ( on the sides of the carbs) , idk how to ajust them but from what i read on the internet if there not right the banshee doesnt run right?

 

Reading the plugs is a very good way to see how the engine is acting. There is a right way and a wrong way to check them. You have to warm it up, then accelerate to 3rd gear full speed and kill the spark plug by the kill switch and immediately come to a stop and pull out a plug. See what it looks like and white is definitely bad. Google: how to read a spark plug and you will see pics of what good and bad plugs look like.

 

Generally speaking, if it bogs then speeds up, it's running rich, if it's bogging late in the rpm's, you have done engine damage by running it too lean. Now that you have removed the air filter sock from the intake, the jetting it had may be fine. If it seems real fast, stop. It is running too lean and that is how you blow it up. Smoke coming from the exhaust is a good thing. It means it has oil protecting it.

[AKheathen]

couple things not right there.......1st, the bog for a second then pick up power, is a clasic lean hesitation. rich, it will sputter first and not pick back up untill you get the throttle in a leaner spot, remove the load, ir will just die. there is also a proper plug chop procedure that yoiu can search for on here, which you put a brand new plug in a warm engine, wot for at least 10 seconds, then cut the threads off and read the ring on the bottom of the porcelin. without a new plug, you are just getting an average history reading, but doesn't tell much. start with the mains via plug chop, then set the needles, and finally pilots and airscrews. the screws on the side are the idle screws that the slides rest on. look up syncing the carbs and it will tell you how to set the cables even, then the idlescews matched, then the cables again......the 340 main and 30 pilot is a good safe place to start for sea level and cool temps....