Jetting stadstill

[01banch]

Banshee Mods-

PT midrange pipes

K+N pods

Cool Head 20CC domes

Port-Unknown could be stock

Carbs-Stock No Tors

Main Jet-420

Weather-45*

 

Runs great I have tried 430 but the plug is black with the 420 it is black on one side light tan on the other bottom of the threads are clean pictures might be able to show you what I am jabbering about. They are the same plug taken at the saem time both sides have the identical plug more or less.

[01banch]

So the plug type is a BR8ES and I cannot spell standstill :biggrin:

[01banch]

bump

[01banch]

BTW I am at 3500 feet

[01banch]

Am I missing something that is seen as pertinent information? any input would be nice.

[AKheathen]

what oil are you running?

[rubberneck]

Wow, that is a huge main jet. Im not sure about the pt pipes, but with t5s, k&n pods sea level, i run 320-340 depending on temp. At 3500 ft i think i would be in the range of 300-320. Have you done a leak down test to make sure there are no air leaks?

[elwilliams13]

I got the same pipes on a 4mil and I run stock carbs with 280 mains and I am a hair rich.

[01banch]

Wow thats what I thought I did a leakdown test and nadda that is why I am not sure what is happening I will continue my search into this I am stumped

 

BTW I am running 40:1 golden spectro

[01banch]

Maybe Ill just toss the 430's back in there and let it run a bit rich

[elwilliams13]

Something is up is it a 430 or a 340 main? Because that is a low to mid pipe makes most of the power in the midrange did you say it was ported?

[01banch]

I ran a 430 in it when i Rode it at sea level the plugs looked great, I brought it home to 3500 Feet and it was rich Obviously so i decided to drop a size on the main jet and see were it stood, well it ran the best the bike ever has but when i did a plug check they looked like the pictures I took...I do not know for 100% if it is ported or not, But I would thikn that if it shows a black wet plug with the 430's in it that rules out a air leak but I do not know for sure. I was just a little suprised to see that size of jet in there as well that is why I came and posted and see if you guys had some input that may lead me in the right direction. I may have to tear into it to see if it is ported or not and check piston conditions.

Edited February 18, 2009 by 01banch

[sleeper06]

I had a bike come through here running 440 mains 32.5 pilots,serios porting and tunnelling with t-5s,140psi. I am at sea level. Are u running pump gas in your bike with 20cc domes because that would be a hint into your port work. just because your plug color changes with jet change doesnt mean theres no air leak you could be chasing a problem.You bought the bike like this or redid it yourself

 

Make sure it holds 6psi for 6min

[01banch]

I run premium non ethanol I bought the bike and it was setup with Cpi's instead of the PT's Midranges and it always ran like crap so i traded the cpi's for the Pt's and it runs leeps and bounds better than it did before i never looked at the ports or anything i just had always assumed it was stock porting but then i went to rejet it for 3500 feet so i could ride it around my house and saw the 430's I threw in the 420's and it runs great but I do not like how the plugs look, The reason I ruled out air leak was the fact that it was running rich. meaning that if you can get it to run rich then a air leak would have to me miniscule and would still pass a leak down test with 1 psi a miinute being lost, I know that on my 250r I had a bad air leak I could jump up 10 jet sizes and it would still run lean so it may be that I am looking at it all wrong I guess ill dig into it some more and look for possible air leaks, What are the normal places that air leaks occur on a banshee I checked the boots I also checkd the O rings in the head and the base gaskt the is no vissible leaks and i sprayed then with carb cleaner there was no change in rpms.

[sleeper06]

I was told there is acceptable loss but im a perfectionist,You can make a leak down tester for $20-$30 dollars at local hardware store. I wanted know octane value because premium is diffrent in certain places.If your running 93 with no problem you have decent porting with 20cc domes

 

Also keep in mind a notorious air leak spot is behind the clutch cover,through the keyway on the primary drive gear,if keyway doesnt have case sealer all through there you would be extremely lucky to not have an air leak.