daddyo Posted October 24, 2008 Report Share Posted October 24, 2008 I got a 87 ported pollished little bigger carbs duel k&n filters trinity stator. The thing runs great just got no low to mid range. any help?? Quote Link to comment Share on other sites More sharing options...
magz Posted October 24, 2008 Report Share Posted October 24, 2008 bigger carbs and porting do that to the bike, go to some 28 carbs and get a timing plate, maybe drop a tooth on the rear and front sprocket for quick fixes. Quote Link to comment Share on other sites More sharing options...
daddyo Posted October 25, 2008 Author Report Share Posted October 25, 2008 Well I took the stator cover off and what I have is a stage 4 stator so I bumped the timing up +4 seams to help A little. If I am on the streat in third and about mid range and stab it, it takes about 2 seconds for it to do anything.I am running a13 up front and a 41 out back running 91 oct. should I run hotter fuel?? Quote Link to comment Share on other sites More sharing options...
deckheight Posted October 26, 2008 Report Share Posted October 26, 2008 (edited) It is not all that unusual with lower compressions (pump gas), aggresive exhaust port timing and bigger carbs (33mm +)) to have a dead spot. Sometimes they get real sensitive to changing RAD conditions and carb tuning can be a real PITA... Keep it at a constant throttle setting for 60 seconds or more and nail it. If it "hesitates" like you describe when you grab a handfull it's lean. If it "blubbers" your rich... Sounds like maybe you need bigger pilot jets and/or to raise the needles a notch. Slightley rich jetting produces a little bit better botton end anyway. If jetting doesn't correct it... All you have left is lower gearing and/or higher compression, but your carbs need to be metering fuel correctly regardless. Kinda sounds like your already fairly close since you don't mention a problem in 1st or 2nd. Doesn't sound like a fuel octane issue to me, wouldn't hurt to try some 100 octane before going through all the carb drama though, see what happens??? Good luck On edit: Make sure your carbs are synced too... Well I took the stator cover off and what I have is a stage 4 stator so I bumped the timing up +4 seams to help A little. If I am on the streat in third and about mid range and stab it, it takes about 2 seconds for it to do anything.I am running a13 up front and a 41 out back running 91 oct. should I run hotter fuel?? Edited October 26, 2008 by deckheight Quote Link to comment Share on other sites More sharing options...
05.Banshee.SE Posted October 26, 2008 Report Share Posted October 26, 2008 Head & domes? Quote Link to comment Share on other sites More sharing options...
daddyo Posted October 26, 2008 Author Report Share Posted October 26, 2008 Thanks guys I'll keep tinkering on it. Trying to get ready for dumont halloween.. Quote Link to comment Share on other sites More sharing options...
daddyo Posted October 28, 2008 Author Report Share Posted October 28, 2008 I also niticed when I took my carbs apart and i only have a 140 main I put a 145 in and it seamed worse. From what i hear alot of you guys are ronning about a 200 plus. does that sound right? Quote Link to comment Share on other sites More sharing options...
THE GRIM RIPPER Posted October 28, 2008 Report Share Posted October 28, 2008 Yes 200 plus on stock carbs.... Tell these guys the exact carb size and brand... Jetting sizes are different for different brand carbs Quote Link to comment Share on other sites More sharing options...
daddyo Posted October 29, 2008 Author Report Share Posted October 29, 2008 I talked to buddy of mine and he told me keihin carbs run different sizes I got 30 keihin carbs with a 140 main and a 40 pilot. but just ordered vf3 reeds. I am thinking maby a 150 or 155 main once i get those reeds on what cha think? I only run sand and mostly dumont.. Quote Link to comment Share on other sites More sharing options...
Washburn Posted October 29, 2008 Report Share Posted October 29, 2008 You might have an all topend port job and thats gonna get you around in the dunes and if you want a little more lowend/mid range get a Noss Head with smaller domes and a timing plate set at +4 if you want to stay on pump gas Quote Link to comment Share on other sites More sharing options...
Tim Potteiger Posted October 29, 2008 Report Share Posted October 29, 2008 I got a 87 ported pollished little bigger carbs duel k&n filters trinity stator. The thing runs great just got no low to mid range. any help?? 2 strokes in general, and especially Banshees are very notorious for having a "dead" spot before the power really comes on. "Hotter fuel" as you call it (high octane fuels actually burn cooler and slower than normal pump gas) will not change this. That being said, you might require higher octane if you make the necessary changes to get some low end. Your only hope for better low end would be higher compression and/or more timing advance. The, other, and possibly most important factor, in 2 stroke power delivery is the pipe. What pipes are you running? I run 18cc domes and 3+ timing advance on a motor that is ported but the port timing is not changed. I run 36mm Lectron carbs (huge for my motor/porting setup), and yet my power curve is very smooth with tons of low end. I absolutely despise riding bikes with most engine builders' port work. They always modify the port timing and raise the exhaust port for maximum horsepower gain. In doing so, they frequently ruin the ride-ability of the motor. The number a dyno puts out means nothing if you just like to ride. The way in the which the power is delivered throughout the RPM range is what is important. If you bump the compression and timing and find the motor still doesn't satisfy your low RPM desires then you might consider dumping your ported cylinders and going back to a set of stock cylinders or possibly getting a set ported that would be more suitable to your riding style. Quote Link to comment Share on other sites More sharing options...
daddyo Posted October 29, 2008 Author Report Share Posted October 29, 2008 I got fmf gold series pipes fmf silencers, bored but not shure how big, 30 mm keihin carbs, 140 mains 40 pilots soon to have vf3 reeds on the way. ported polished +4 advance on a stage 4 stator 13 front 41 back duel k&n filters and a crappy mid range that if I stab it from mid throttle sits there and does nothing till the motor feels like it . Hopefully when I get vf3 reeds and re jet it it will solve the mid prob. I dont really need to run trick yet right?? do I?? I really appreciate all the help everybody has given . This is my first shee I used to ride a cr 500 till it tried to kill me two years ago on president's day at comp at dumont. It tried to put the handle bars through my leg at the joint. still got a knot there. Quote Link to comment Share on other sites More sharing options...
burleybanshee Posted October 29, 2008 Report Share Posted October 29, 2008 your pilot seems a little small for 30's, i know large pwk's it would be right. You should be around 45 pilot and 145 to 150 main, depending on your porting and altitude. Do a compression check and see what you have on each cylinder as well. Might let you know if you need to re-ring, might also help the midrange. Quote Link to comment Share on other sites More sharing options...
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