| Author | Message | ||
     Woodbutcher |
hey guys... so here goes. myself, my wife, and my brother have 3 buells in the family. a blast, a S3, and a S1W which i recently acquired from my brother. he took good care of it for the last 5 years, but wanted to see it ridden more, so i bought it from him. the first thing i did-being very familiar with CV carbs- was strip the carb out, see what jets i was working with, and put her back together. 190 main 45 pilot 4th clip on needle (jet kit) 2.5 turns out air screw when i put her back together and took her for a spin, she ran fine (LOTS of pop pop pop on decel... thats a side issue), but there was some oilish gas streaks on the subframe just rear of the air cleaner. i swore it was the breather bolts... so i cleaned them up, put some permatex ultra black on the bolts and let it sit for a day and dry. that didnt fix the dribbles so i bought new gaskets for the carb to bracket, brack to air filter, and still some streaks after a brisk 3 mile tour... well, i parked the bike while still at idle, took off the Force Winder air cleaner and revved the engine... this thing is misting out gas like nobody's business! here the whole time i thought it was the carb boot to intake leaking, a gasket etc... 100 bucks says this Force Winder air cleaner doesnt seat properly against the aluminum oval plate, and the spitting/misting carb gas is leaking in between the filter and aluminum frame. i can seal it with some black rtv, i just didnt know what you guys thought. the only mods the bike has is: Bartels air cleaner with K&N filter KT pipe Thunderheader can Race ignition i have an extra force winder exhaust i am going to put on to test it out and verify everything inside of the air cleaner is sealed up. here is the video and picture below. https://youtu.be/OSXLxXeRfNM  | ||
| Buell_m2_s3 |
From the video it appears to do the same on mine so it I think it is normal? Since you are getting a blast of fuel from accelerator pump it could be just that it likes to slobber. I could be wrong (Message edited by Buell M2 S3 on August 31, 2015) | ||
| Blackm2 |
If it has been sitting for awhile, it may have solidified fuel in those tiny orifices next to the atomizer. Stick something like a small paper clip in there to ream them out. Carb cleaner may not clear it. I removed this CV40 off of my current S1 that had been sitting for years. I had put it on my Cyclone when I sold it after cleaning it thoroughly, or so I thought. https://www.youtube.com/watch?v=d1aMkae0ltE | ||
| Blackm2 |
Oh and that oil spray is most likely coming from that rear head breather bolt, that 90 degree one. Mine was doing the same thing on the S1. I removed it and put the same breather set up that is in that cv40 video. | ||
| Woodbutcher |
its definitely not the breather bolts. its the same thing i thought.. but as you can see the mist spray in on the front of the tube.. the breather bolts are dry as a bone and are slightly inset from the tube. the carb was really cleaned well but i can check. i bet you the force winder solves it. anything that spits out is going right back in! i do like the looks of this one though...  | ||
| Akbuell |
My totally stock '01 X-1 did the same thing. I believe oil vapors from the crankcase mix w/the fuel vapors in the airbox, then drain out into the airstream. For me, the fix was to install XB rocker covers. Simple fix, and eliminates one gasket surface. Downside is having to run lines, either over the side or to a catch can. The blowback is pretty much the nature of the engine. If you have every watched one of these run on a dyno, w/the aircleaner off, there is a lot of mist blowing out the intake system, even at WOT. I believe it is due to the relatively short distance from the slide (or throttle plate for FI engines) to the intake valve(s) in relation to the diameter of the intake tract. Hence the (relatively) really long intakes on the XR750. When the intake valve closes, a pressure wave builds up at the valve head, and 'echoes' back to the carb/throttle body, causing the blowback. Hope this helps, Dave | ||
| Alfau |
Valve umbrellas in the rocker box | ||
| Bluzm2 |
It's called reversion. Interesting stuff! Part of it stems from the smallish air filter. The bigger race can has more surface area to absorb then release the drool. | ||
| Jolly |
Ive got the same problem on my 96 S1, but not on my 98 S1W both running the exact same air cleaner and XB rocker box cover conversion with catch can...and both still running CV carbs... I'm tempted to buy a whole crate load of mikuni's and see if that fixes the problem...then put one on every carb Buell I own. my S2 (CV carb) drools/leaks after I shut it off...  | ||
| Hootowl |
"my S2 (CV carb) drools/leaks after I shut it off..." Check to see if the fuel inlet elbow is leaking. Stock is two piece brass/plastic. The plastic bit can develop small cracks and weep fuel. | ||
| Jolly |
Hootowl, excellent advice...already replaced with the brass fitting.... | ||
| Woodbutcher |
well guys, it was the chinsy air filter to frame seal on the Bartels that was the problem.. put on the forcewinder and went for a spirited ride for 15 minutes... not a drop on the frame... and i put nothing on the breather bolts ( no loctite or rtv). i actually like the look and feel of this cleaner better. it allows me to 'hug' the frame with my knees while riding which im used to with other bikes.  i will create another post, but have a decel popping issue i need to solve. 1. i am getting extreme decel popping. from 2-4k rpms. in fact, i can rev the bike at a standstill when warm and it 'bumbles' on decel... but on natural engine braking, while slowing down its more of a loud pop pop pop....only way to stop it is to crack the throttle while braking... quite annoying. upgrades: ForceWinder KT pipe (bigger) Thunderheader can (pretty open) Race ignition 45 pilot 190 main 4th clip 1-3 turns out doesnt matter on air screw. thats it... i put a 48 pilot in it instead of the 45 currently and it decreased it to bumbles on decel... no loud popping anymore. one would think that means it needs the 48 pilot.. but i think its may be more of an exhaust gasket leak (i have new ones, but need to install them). the reason i think its exhaust rather than too lean of a pilot circuit is that when i do the idle drop test with even the 45 pilot, the bike wont die/stall until 1/2 turn from seated! to me that means a 42 would suffice at 2.5-3.5 turns out.. no? next step is to replace the exhaust gaskets to eliminate that, otherwise this is all just speculation. | ||
| S1owner |
thunder header might be your issue I have never used them but have heard over and over they are impossible to tune to. | ||
| Woodbutcher |
whats a popular throaty sound for these tubers? i love the sound. and its even got that nice raspy decel noise when upshifting.. but this popping is nuts. a bit too little back pressure im thinkin. | ||
| S1owner |
Theres several out there. Sound is hard as everyone has a diffrent thought. Here is a clip of mine with a 2.5" header and a dadams pipe I love the sound http://youtu.be/JjzUPhrhBjM | ||
| Woodbutcher |
sounds like mine. actually im not too worried about the note coming out of a push rod... im sure they all sound good... i would rather have tunability. | ||
| Coxster |
I have my breather tubes going over the engine to plastic tubing. So far no leaks. The oil runs back in I guess. I just had my fill of the VH can coming loose at the end plate and tearing up. I took out the damaged baffle and welded the endcap on. I can feel a loss at 4000 compared to before but it still pulls good at 4500-5500 and she snarls like a mean dog. Drowns out rap music at intersections too | ||
| S1owner |
Heres a link about thunder header http://www.badweatherbikers.com/buell/messages/476 23/736997.html Pay attention to the last comment Firemanjim knows his stuff | ||
| Woodbutcher |
thanks guys. ill check out the thunder link. i am installing the 'washer bolt' technique others have used to increase back pressure to decrease the popping/extend valve life in straight race pipes. we shall see what happens. see here. http://www.tabperformance.com/Reduce-Back-Pressure -Exhaust-s/203.htm |
