hops Posted July 18, 2004 Report Share Posted July 18, 2004 (edited) Right now, starts great, low end is good, topend is "great", but right before is hits the pipe, it blubbers and stumbles, then takes off like a rocket. Orignally tried "toomey style" needles, but went back to stock and it helped a bit, but not enough for my liking. Don't get me wrong, the bike is ridable, it is just bothersome considering my stock gearing, 22in 9 paddle tires, and what kind of riding I've been doing. Plugs tend to be rich off the pipe, clean up on the pipe: almost too much(plug? see below) Considering what I've given you to work with, what ya'll think? I'm pretty sure its just a needle move, but which way? down(clip up)? Also, how much of a difference will a B9-ES vs. a B8-ES NGK plug make? I know the difference is the heat range, but is it that big a difference? (ie, if I go back to a 8, will I have to reduce the mains cause of the cooler temp?) 30 or 32.5 pilot stock needle, middle (or clip 1 down from middle) 360 mains 165+ lbs compression +6/7 timing VP 110 @ 40:1 yamalube see below for mods...before I keep rambling Edited July 18, 2004 by hops Quote Link to comment Share on other sites More sharing options...
PlaynSand Posted July 18, 2004 Report Share Posted July 18, 2004 I had similair issues when tuning my ported 350 with stock carbs. Would always sputter at the begining of the midrange then clear out and run. was'nt real bad but bothered the crap outa me . I had some LRD needles but they were too lean and would cause a bog at the start of the mid no matter what main I put in it . The stock needles caused a sputter but were better if I ran the clip at the top , also stock pilots helped a little more over the 30's . Never really found a cure , so stockers are on the shelf now and running PWK's . I was visiting with a engine builder from Kansas , ((not naming any names)) And he was telling me that the stock needles would never work properly on a ported engine and to get some RZ needles and run as big a main as it would stand , but he said the stock carbs would rob it of a lot of power and it would be better to run aftermarket carbs. I don't know if all he said was true , but he was handing everyone their ass in the drags riding a 535 Cheetha with +10 swingarm and 25" paddles. I never found any RZ needles , so I gave up and bought the Keihins. Quote Link to comment Share on other sites More sharing options...
nickxc Posted July 18, 2004 Report Share Posted July 18, 2004 you said you went back to stock needles and it helped. toomey needles are longer than stock so if stock needles helped Id say you are prolly lein and need to raise your needle by lowering the clip position... try running it at the rpm that it is studdering and pull your choke 1/2 way out and see if it gets worse or better. if better you are lein, if worse you are rich... Quote Link to comment Share on other sites More sharing options...
bbluebanshee Posted July 19, 2004 Report Share Posted July 19, 2004 i just had the same problem on my gf's banshee. i had the needle on the second from the top and blubbered at 1/2to3/4 throttle. i dropped the needle progressively to the clip before the lowest position and it runs super strong now. no dead spots or blubbering. Quote Link to comment Share on other sites More sharing options...
Big Bad Banshee Posted July 22, 2004 Report Share Posted July 22, 2004 I have built a few 4mm stroker motors, and the 1st thing I would do is set the timing at 4% 6 or 7 is to much unless you are running alky Quote Link to comment Share on other sites More sharing options...
hops Posted July 22, 2004 Author Report Share Posted July 22, 2004 Thanks for all the responses. I'm gonna get to run it this coming "weekend" (sunday-tuesday), and will be able to open her up near the parking lot, so tuning will be easier as I don't like opening the carbs while on the sand. My thoughts are to put in the b8-es plugs, check the main, then try the choke trick and go from there. I know the stock carbs aren't ideal, but atleast they are bored to 28... As far as timing, that's what the builder set it to, so unless I have other issues, it will stay until I have more work done. (But I probably could drop octane if I did??) I will try and let ya'll know how it goes. And as always, if someone has something to add, please feel free. Quote Link to comment Share on other sites More sharing options...
Banchetta Posted July 25, 2004 Report Share Posted July 25, 2004 I'd say lean the needle out. Lower the needle by raising the clip towards the blunt end.... Quote Link to comment Share on other sites More sharing options...
hops Posted July 28, 2004 Author Report Share Posted July 28, 2004 Well, I had even worse luck this weekend. Was running a 360 main, no color. Went the the store, threw in a 380, no color. Went back to the store, finally threw in a 410. PHUK, no color. It was dry and hot, but really now, that's quite a jump just for weather. I was probably border line lean on previous trips, but I atleast got some color on the porcelin. And this is both plugs, not just one side, so I think that rules out an air leak. My only thought is the timing is too advanced, like stated above. Would this cause the plugs to show no color? Its either that, or I've been running extremely lean for like 5 trips now, and the builder don't know schitt. HELP Quote Link to comment Share on other sites More sharing options...
sredish Posted July 29, 2004 Report Share Posted July 29, 2004 Well, I had even worse luck this weekend. Was running a 360 main, no color. Went the the store, threw in a 380, no color. Went back to the store, finally threw in a 410. PHUK, no color. It was dry and hot, but really now, that's quite a jump just for weather. I was probably border line lean on previous trips, but I atleast got some color on the porcelin. And this is both plugs, not just one side, so I think that rules out an air leak. My only thought is the timing is too advanced, like stated above. Would this cause the plugs to show no color? Its either that, or I've been running extremely lean for like 5 trips now, and the builder don't know schitt. HELP well, hot and dry would mean you'd need to lean out, not richen. I would still check for air leaks. timing can possibly lean some, but not all the way to 410s. how is your airbox setup? if your quad was running good on top, then why did you mess with the mains, a midthrottle burble is in the needle, or is this at full throttle? you could have something loose after jetting and rejetting over and over. Quote Link to comment Share on other sites More sharing options...
hops Posted July 30, 2004 Author Report Share Posted July 30, 2004 Yeah, talked to the builder, wants me to check for air leaks too. Running freshly cleaned dual clamp on K/N's with outerwears. It wasn't running good, so I checked the plugs is why I started with the mains. No color, and couldn't get it to bog either. Got somethin goin on, gonna try to look at this next week. Just happy to still have it, someone took off with my trailer, two bikes, and dumped em off in an apt complex down the street...Had the lock that goes into the ball hitch, they couldn't get it too far jerry rigged on the hitch. Too bad I didn't catch em in the act. Thanks guys, I'll see what I can find out. Great site, great source of info. I'll be back.. Quote Link to comment Share on other sites More sharing options...
sredish Posted July 30, 2004 Report Share Posted July 30, 2004 Just happy to still have it, someone took off with my trailer, two bikes, and dumped em off in an apt complex down the street...Had the lock that goes into the ball hitch, they couldn't get it too far jerry rigged on the hitch. Too bad I didn't catch em in the act. God damn! I'd have buckshot chasin their asses!! Quote Link to comment Share on other sites More sharing options...
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