Jtw Posted September 17, 2010 Report Share Posted September 17, 2010 okay bought a banshee with a t-rex head toomey t-5 pipes and no airbox. when i bought it it needed new crank seals. i replaced them but the bike would bog and never hit power band. my friend said i was probably to rich becasue of the white smoke. my main jet was 180 and pilot 50, i went down to 175 and the highest clip on my needle but still cant hit the powerband right. my elevation is roughly 3700. i ride in mid 90 weather, and i have keihin pwk 36mm. any help would be great. thanks Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted September 17, 2010 Report Share Posted September 17, 2010 You need a pressure test on that motor before you can jet affectivley,compression test,tell us what size domes,race gas/pump gas,timing,who determined the crank seals were bad and if so what other damage was done Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 17, 2010 Author Report Share Posted September 17, 2010 (edited) You need a pressure test on that motor before you can jet affectivley,compression test,tell us what size domes,race gas/pump gas,timing,who determined the crank seals were bad and if so what other damage was done ok my compression is roughly 130, i havent done a pressure test and have know idea how to check the timing. no damage was done to motor when the crank seals were replaced, had the mechanic check it out. prior to the seals being changed the carbs were set with 180 main and 50 pilot, and would idle fine. after the shop replaced the seals the told me they needed to rejett the carbs with a 175 main. i told them id do it becuase they were gonna charge almost 200 bucks. i went and purchased the 175 mains and installed them my self on my keihin pwk 36mm carbs, i still had the same issue. bike runs but wont hit powerband. so then i went and purchased 162 mains to see if that would give a diffrent result, but still the same outcome. the bike no longer idles and i have no clue which way to go on my jet or pilot. spark plug is a little wet and a very light grey. sorry i couldnt give you the other info u asked for??? shop swears its due to jetting pump gas no clue domes Edited September 17, 2010 by Jtw Quote Link to comment Share on other sites More sharing options...
350 twin Posted September 17, 2010 Report Share Posted September 17, 2010 mine was completely stock my main jet was 200 and pilot was 25. I just installed a 280 main and a 30 pilot and took off the air box snorkel 2.5 turns on the mix screw,wow what a difference, i only added a fmf fatty pipe Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 17, 2010 Author Report Share Posted September 17, 2010 Are u riding at my elevation? Quote Link to comment Share on other sites More sharing options...
350 twin Posted September 18, 2010 Report Share Posted September 18, 2010 not sure of the elevation in indiana Quote Link to comment Share on other sites More sharing options...
Overboost Posted September 18, 2010 Report Share Posted September 18, 2010 if your engine is tip top and no other problems, your jetting is WAY off considering, again you have NO issues with the engine, your jetting I would start at a 145 main and a 42 pilot, being I have way more going than you with smaller carbs and I am only running 160 main and 45 pilot. as the others said, test the engine first to be sure your only hosed in your jetting pressure and leak down test it Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted September 18, 2010 Report Share Posted September 18, 2010 Dude said he has a t-rex thats alot going on,supposidly they pull fuel real well and dont need abnormally large jets.Take a pic of the bike and post it up mainly the motor/carbs.If there is one thing thats totally necesary its a pressure test,the whole process is listed in a sticky at the top of the forum and its rather cheap to build.Where are you from?You should be able to idle on a 50 pilot.Also check the plug caps if you get no response by leaning it out might have a spark issue.130 psi seems low on a trex build in my opinion,usually they are drag/race motors on high octane Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 18, 2010 Author Report Share Posted September 18, 2010 Ok thanks for the help guys. I will post pics later tonight. I got a hold of some 40 pilots and 145 mains here locally so I'm gonna put this in. After measuring my carbs they are actually 33 mm. The guy i bought it from told me 36mm. If this fails I'm gonna biuld that pressure test setup. I'm in el paso Texas wich is roughly 3700ft. I believe the bike came from Phoenix. Not sure their elevation. Thanks for help guys. If I do have a pressure leak. What in tale will I shave to do to fix it. I assume find the leak and replace gaskets???Please keep the input coming!! Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 19, 2010 Author Report Share Posted September 19, 2010 ok i put in the 145 mains and 40 pilots. big diffrence, seems a little hesitant at first but finally hits the power band im think its a little lean now though, as i said the guy told me it had 36mm but it has 33's on it. im thinking of going to 42 or 45 pilot and 150 or 155 main. i tryed the 40 pilot with the 162 and didnt work at all. still sluggish. i did notice a funny noise though when i ran the 40 pilot and 145 mains. i checked my pluggs and the were black. i took the pic on my iphone so not sure how the quality will come out. i also posted the a youtube video so you guys can tell me what you think that noise is. thanks Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 19, 2010 Author Report Share Posted September 19, 2010 and heres a pic of that plug Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted September 19, 2010 Report Share Posted September 19, 2010 sounded like you were running on one at idle,I would almost bet your plug caps ohm out bad.cap tp cap with a meter i think its supposed to be between 3.5-7.0 but most come in at 5.5.You need new exhaust orings for sure.The pressure test is insurance that your not chasing a problem when jetting same with plug caps.I tune alot of peoples shit If I didnt build it gets three tests,pressure/comp/plug caps.I have chased my tale too many times because of neglectful people.Did you sink your carbs? Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 19, 2010 Author Report Share Posted September 19, 2010 (edited) sounded like you were running on one at idle,I would almost bet your plug caps ohm out bad.cap tp cap with a meter i think its supposed to be between 3.5-7.0 but most come in at 5.5.You need new exhaust orings for sure.The pressure test is insurance that your not chasing a problem when jetting same with plug caps.I tune alot of peoples shit If I didnt build it gets three tests,pressure/comp/plug caps.I have chased my tale too many times because of neglectful people.Did you sink your carbs? so your saying you think i was only running one piston on idle?.... due to the plug cap. hmm..... do i just replace the caps if there bad? i am aware i need new o rings, the shop that installed the crank seals was supose to do that as well, its on my receipt. bastards. i will be doing a pressure probably this week. i also had another question. my carbs are in sync i think but i have to adjust the throttle cable to get the bike to idle. the slides look a little lifted because of this.the idle screws on the carbs do nothing at all. is this normal or should my slides be complettly down. its weird because the bike used to idle fine when i had the 180 mains with the 50 pilots, however it did have a twist throttle on it before. oh ya and by the color of the plug in the pic do you think im lean or rich?? Edited September 19, 2010 by Jtw Quote Link to comment Share on other sites More sharing options...
Jtw Posted September 20, 2010 Author Report Share Posted September 20, 2010 so your saying you think i was only running one piston on idle?.... due to the plug cap. hmm..... do i just replace the caps if there bad? i am aware i need new o rings, the shop that installed the crank seals was supose to do that as well, its on my receipt. bastards. i will be doing a pressure probably this week. i also had another question. my carbs are in sync i think but i have to adjust the throttle cable to get the bike to idle. the slides look a little lifted because of this.the idle screws on the carbs do nothing at all. is this normal or should my slides be complettly down. its weird because the bike used to idle fine when i had the 180 mains with the 50 pilots, however it did have a twist throttle on it before. oh ya and by the color of the plug in the pic do you think im lean or rich?? ok was able to get the slides synced up right and idle. the bike is freakin fast with the throttle wide open but it feels like it builds up before it goes. is this related to my pilot. do u guys think i should lean it out some more. maybe like 35-or 37. its like it has no torqure at first or bottom end but then just opens up like a bat out of hell. i changed the plug caps and spark plugs like you suggested sleeper, made a diffrence. plus that funny noise was due to the actuall exhaust springs not connected.on the left side. i really want that bottom end because i trail ride all the time.il never really need that throttle open that wide. to be honest this bike probably has to much motor for how i ride. probably should have stuck to 4 stroke. i miss my yfz :-( with all these problems involved with tunning. let me know what you guys think. you guys have gotten me really far with your help! Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted September 20, 2010 Report Share Posted September 20, 2010 Check to make sure there is a CEL needle in the slide,if not get two,there a leaner needle than supplied with the the carb and work well,also 38 pilot is the leanest pilot they make for the pwks.I would try the leaner needles first,plus they sell a vacuum guage for syncing carbs,Call jeff from fast numbers in my sig he can hook you up with everything including jetting info Quote Link to comment Share on other sites More sharing options...
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