Gobbler Posted May 16, 2004 Report Share Posted May 16, 2004 Hi guys, I've been trying to get this jetting right for over 2 months now and I've got no were near it. My problem is the usual bogging down in 5th and 6th gear. When you shift into 5th open the throttle you get the same sound as you would kicking the engine over with full throttle open. If I pull the choke out fully in 5th, the bike pulls like it should to the top of 6th. Now this would tell me the bike has a lean condition on the mains circuit. Now before I go any futher the bikes stock except for a K&N pod filter with no airbox surounding. I cut the box off and dont use the radiator ressie. Now I originally had the bike running well with stock pilots, a dynojet needle in the middle clip and 270 mains. One day riding 2 months ago the bike all of a sudden developed a bog at WOT in 4th that made it impossible to get into 5th. I'm now at the point of same pilots and needle and 310 mains and still no real difference. I've done the following aswell: - checked the float height ( 21-22mm) OK - checked the float needle and seat for wear OK - cleaned the slides, adjusted the carb sync and its fine - checked the reeds for noticable wear or breaks OK - Placed new gaskets on the intake manifold to rule out engine side intake air leaks - replaced sparkplugs and checked the coil for correct output OK - cleaned the flywheel ignition points and the magnetic pickup ( rusted a bit ) - cleaned out the fuel petcock filter, replaced the fuel line to the carbs and removed the inline filter I had. - obviously cleaned the K&N filter and I dont oil it either as I have a new outerware on it I don't know what next to do. I personally think 310 mains are way to rich but when the chokes pulled the bike runs sweet up top. Thats why Im confused. As a comparison, my friend has T-6's on his with V-force reeds and dual filters on each carbs and he runs 300 mains and thats fine. BTW I'm also at sea level. I'm thinking of rebuilding the carbs with all new parts really only because I haven't done that yet I think its purely a carby problem because of the choke pull test I did in 5th and not an engine or electrical problem, but after all the checks Ive done on the carbs Im totally confused ?!?!!?!? What do I do next....... Plz help me someone Quote Link to comment Share on other sites More sharing options...
Schizo Posted May 16, 2004 Report Share Posted May 16, 2004 If it runs better when you pull the choke i would think it would be a lean main. What do the plugs look like? They will tell you if its rich or lean. Quote Link to comment Share on other sites More sharing options...
Gobbler Posted May 16, 2004 Author Report Share Posted May 16, 2004 I cant do a WOT test on the plugs because I cant run in 5th or 6th without pulling he choke. If I do the test with the choke pulled wouldn't that defeat the purpose of doing it ? Quote Link to comment Share on other sites More sharing options...
sredish Posted May 16, 2004 Report Share Posted May 16, 2004 have you ran a plug check with the 310? i'd run a plug check and keep going up on the mains till you get a definite rich setting or your plugs tell you when it's there. i'm also confused, you have stock pipes or aftermarket? a WOT plug check in 6th is the best way to know how your main is. Quote Link to comment Share on other sites More sharing options...
Holyman Posted May 16, 2004 Report Share Posted May 16, 2004 I would never run the filter un oiled. Try oiling the filter, it might restrict it enough to richen things up a bit and you won't run the risk of dust in the engine. Next remove the screens from the inside of the tank and go back with an in- line filter. That way you will know you are getting gas when it needs it most. Quote Link to comment Share on other sites More sharing options...
Gobbler Posted May 16, 2004 Author Report Share Posted May 16, 2004 I will re-oil the filter but I dont have a fuel supply issue i think because when I ran the bike with the choke fully out at WOT in 6th, I did it for like 1km at least and if I did have a fuel restriction it would have shown up then I would of thought. This has become a Quote Link to comment Share on other sites More sharing options...
Gobbler Posted May 16, 2004 Author Report Share Posted May 16, 2004 (edited) have you ran a plug check with the 310? i'd run a plug check and keep going up on the mains till you get a definite rich setting or your plugs tell you when it's there. i'm also confused, you have stock pipes or aftermarket? a WOT plug check in 6th is the best way to know how your main is. sredish, I have stock pipes on the bike, the only differnec is the K&N filter and the rests stock. Do I bother a WOT test in 6th with the choke fully out ? Thats the only way I can do it. Edited May 16, 2004 by Gobbler Quote Link to comment Share on other sites More sharing options...
Rescuejeff Posted May 16, 2004 Report Share Posted May 16, 2004 Gobbler try not putting a thick coat of oil on the filter, it could restrict your air flow and make it tooo rich at WOT in your higher gears. What is you main and pilots??? You have to rejet with a K&N and lid off. Let us know. Quote Link to comment Share on other sites More sharing options...
Gobbler Posted May 16, 2004 Author Report Share Posted May 16, 2004 Gobbler try not putting a thick coat of oil on the filter, it could restrict your air flow and make it tooo rich at WOT in your higher gears. What is you main and pilots??? You have to rejet with a K&N and lid off. Let us know. Rescuejeff, The pilots are stock 25's but I have no hesitation from idle to 1/4th throttle. The needle is out of a Stage 2 Dynojet rejet kit I bought with the K&N filter and its in the default postion of clip 3 or middle as per dynojet instructions. The needle seems to be fine aswell, it pulls hard until it bogs up top. The mains at the moment are 310's. I just took the bike for some WOT tests 10 mins ago and with the choke fully in as you would normally the colour of the plugs was a darkish tan brown on one side of the electrode and a medium grey on the other. I also noticed slight dark speckels if you get my drift near the electrode tip. When I did a second test with the choke fully out this time the bike pulls all the way to the top rpm's and the plugs looked slightly darker brown and grey but the speckels were gone. Also to answer you questions about the airbox. I have cut the airfilter suroundings off from at the filter adapter point. The front of the box is still mounted onto the carbs via the rubber boot things and using the two frame mounts on the filter side. The filter just bolts onto its normal adapter point which I've secured to the original airbox front part using some self tappers and silicone to seal it. Its a cheap way of opening the airbox but it works Quote Link to comment Share on other sites More sharing options...
sredish Posted May 16, 2004 Report Share Posted May 16, 2004 I don't think I've seen a stock banshee jetted that high, but it does sound like you need to richen the main another size or so. did you buy the banshee used, are you sure it doesn't have black toomeys that look stock? throw in some 320s and see what happens. Quote Link to comment Share on other sites More sharing options...
Banchetta Posted May 16, 2004 Report Share Posted May 16, 2004 You have a problem....first a few questions, did those speckles on the plugs look like aluminum?? Next, what is your compression? Check that out asap!! If your compression is fine, then I'd do a leakdown test to see if you have a blown crankseal. That'll cause your lean condition, the sudden change in jetting for no reason, and loss of power..... I'd first check the compression and rebuild if necessary, before you take anything apart, I'd make a leakdown tester, there is some great info on duncanracing.com on how to make one. That'll determine whether you have to pull the crank seals to replace them....you have some homework to do now, let us know what you come up w/.. Quote Link to comment Share on other sites More sharing options...
Gobbler Posted May 16, 2004 Author Report Share Posted May 16, 2004 (edited) Thanks Banchetta, The speckles didnt really look like aluminium because they were so small and black in color. The last time I did a compression test was a few weeks ago and I had around 125/127 psi in the L/R cylinders. When I bough the bike in 2001 it had 135 psi in each cylinder new @ sea level. I get into this leak test today and if the seals gone, It looks like a great reason to finally rebuild the motor Edited May 16, 2004 by Gobbler Quote Link to comment Share on other sites More sharing options...
Rescuejeff Posted May 17, 2004 Report Share Posted May 17, 2004 Like Sredish said it sounds lean by teh way the plug looks, but it should run like a raped ape on teh tops if it was lean, What is your mix rate, and I agree about your main, and maybe a slightly higher pilot Good luck Quote Link to comment Share on other sites More sharing options...
SDD Posted May 17, 2004 Report Share Posted May 17, 2004 Gobbler when I took the airbox lid off my girlfriends shee before she had pipes I used 290 main jets with 30 pilots and dynojet needles. With this jetting it ran perfectly at sea level at the dunes (Glamis). No other mods besides the K&N adapter plate and jetting was done. Quote Link to comment Share on other sites More sharing options...
hamuel Posted May 17, 2004 Report Share Posted May 17, 2004 Whats the: mix rate? elevation? Mods:(if any) Temp? humity? Seems no one has aksed. Quote Link to comment Share on other sites More sharing options...
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