liviob Posted October 12, 2011 Author Report Share Posted October 12, 2011 (edited) That was a lot of info BillyT. Thanks for sharing. Yes i have not changed any carb or ignition timing settings recently. Only the air screw. When the bike was new i did experiment with a few different carb settings but found the stock settings to work very well except for raising the clip one slot from #5 to #4. The carb is setup a little rich on the bottom. At first i thought this wasnt good but many experianced trials riders assured me this was necessary for smooth torque not crisp throttle response. Based on your comments i believe this is a cold foul. The plug is oily not overheated to the point of failure. The spark looks normal and is bright blue. I did change the original plug gap from .026 to .020 about eight months ago. And then again with a fresh plug about four months ago. I changed the gap as per recomendation of a friend who said the engine would produce more torque because of the smaller plug gap. Funny thing here is that i did not notice any change in engine performance yet i set the new plug the same before installing it. I personaly thought that a bigger plug gap within recmended range would produce a stronger spark, that was simply an intuitive thought. I do take good care of my bike. It's an 09 and it still looks fresh. I will install a new plug gapped to .026 this weekend. If it fouls again i will assume that worn rings have richend the air fuel mixture due to ring blowby to a point that now fouls plugs. The engine may have about 100-120 hours on it at this point. It still starts easy and runs strong. Although i can push the kicker thru by hand without too much effort. Edited October 12, 2011 by Liviob Quote Link to comment Share on other sites More sharing options...
b40rt Posted October 12, 2011 Report Share Posted October 12, 2011 Has anybody mentioned cleaning your air filter ? If really dirty will make bike run rich, which will help to foul the plug. Quote Link to comment Share on other sites More sharing options...
liviob Posted October 12, 2011 Author Report Share Posted October 12, 2011 (edited) Good point! I do clean it about every two to four rides and reoil it with Belray filter oil. Edited October 12, 2011 by Liviob Quote Link to comment Share on other sites More sharing options...
ham2 Posted October 12, 2011 Report Share Posted October 12, 2011 ...........It is basically matching the gap to get the best out of the mags ability............ The bike in question is a Beta? Are there any Beta Rev3/Evo owners out there who can confirm that the plug fouling is a prelude to ignition failure? I hope that 'The Right Reverend B40RT' is more right than I am . Quote Link to comment Share on other sites More sharing options...
liviob Posted October 12, 2011 Author Report Share Posted October 12, 2011 The bike in question is a Beta? Are there any Beta Rev3/Evo owners out there who can confirm that the plug fouling is a prelude to ignition failure? I hope that 'The Right Reverend B40RT' is more right than I am . I dont think BillyT had ignition failure in mind with his comment, but you do bring up an interesting point. I think i will pull the flywheel and have a look at the stator and check the resistance values and give it a good cleaning. Quote Link to comment Share on other sites More sharing options...
billyt Posted October 12, 2011 Report Share Posted October 12, 2011 (edited) I dont think BillyT had ignition failure in mind with his comment, but you do bring up an interesting point. I think i will pull the flywheel and have a look at the stator and check the resistance values and give it a good cleaning. Livlob Sorry! In my prior brief post (LOL) I was babbiling, not really focusing in with any real solution to your problem! If I am reading your post properly the bike is fouling plugs and they look normal when you pull them. Even though they look normal you feel the bike is running rough at idle or/and low rpm? Changing to a new plug does not fix the problem and it still runs rough? If so the plug is not the issue. if you re-install the same or a new plug it runs the same? The plug condition or symptom is witness to something else that is going on! The bike is not running bad because the plug/s are constantly going bad by themselves or need a slight tweek to the gap. The plugs are going bad due to the bike doing something wacky with the mechanics ie compression, rings, woodruf key, or electrical ie timing, wiring, grounding, magneto etc. You wrote: I changed the gap as per recomendation of a friend who said the engine would produce more torque because of the smaller plug gap. Funny thing here is that i did not notice any change in engine performance yet i set the new plug the same before installing it. I personaly thought that a bigger plug gap within recmended range would produce a stronger spark, that was simply an intuitive thought! That was my point in my looonnngg post. A slight change of the gap of the plug will not effect performance as long as it is in the range suggested by the bike manufacturer. You wrote: "Although i can push the kicker thru by hand without too much effort." what size of bike is this? Being able to push it through by hand may suggest low compression i.e. worn out piston, barrel, rings etc? I am also thinking it could be a ignition (mag, coil) problem, timing, woodruf key or a bad grounding issue of the coil, mag etc.! Even a bad high tension wire. If you just clean the plug you took out and re-install it does it run okay for while and then wet foul plug? I am really not sure how long it runs before it wet fouls a plug. Try this little experiment. Get your bike all warmed up, go to a really dark area such as your garage at night time turn off the lights while the bike is running. Get close to the spark plug area and observe, do you see any sparks around the spark plug area or sparks jumping from the high tension wire to ground? If so then the high tension wire is bad and leaking to ground (by ground I mean the frame etc). There should be no light show in and around the spark plug and spark plug wires. I have witnessed several bikes giving off a light show in a dark area with the spark jumping to the frame off the hi tension lead causing all sorts off intermittent problems! One caveat: because a plug looks wet does not guarantee it is wet fouled. Why? If a plug starts to fail due to the bike running lean and you pull it fairly quickly when you feel something is wrong it will look whitish and dryish. Leave that same plug in for a while and the bike will not run correctly due to the plug being weakened(lean fouled) and it will now wet foul due to not totally burning the fuel, now pull it and it will look wet fouled even though it is actually lean fouled! Confusing I know! It is important that you determine a wet or lean fouled plug ASAP. A lean fouled plug will fail quicker and you will have to change it. If the bike is lean fouling (note fouling as in going bad not totally bad yet) it tends to start easier but runs like crap. A totally lean fouled plug will neither start or run! A wet fouling (getting wetter) plug will run much longer and will make the bike harder to start due to it being wet. Of course when it is totally soaked it too will stop the bike from running or start! Hopefully you will get to the bottom of your problem soon. With lots of good folks supplying good answers/tips I am sure you will. Edited October 12, 2011 by BillyT Quote Link to comment Share on other sites More sharing options...
liviob Posted October 12, 2011 Author Report Share Posted October 12, 2011 (edited) I think i may have figured out the problem. For high altitude riding during the summer 6500'-1100' I have to run the air screw at about 1 3/4 to 2 turns out. During the winter i have to set the air screw out to 2 1/4 to 2 1/2 turns out. I opened it a 1/2 turn the last time i rode it due to cold weather. Today after cleaning it i ran the engine to dry it out and decided to wind the air screw in and count the turns. I found it set at 2 turns out. I opened it another 1/2 turn and the engine smoothed out at low RPM and the throttle became a little bit more crisp. Somehow i lost track of where it was set or Maybe one of my riding buddys turned it? Edited October 12, 2011 by Liviob Quote Link to comment Share on other sites More sharing options...
copemech Posted October 13, 2011 Report Share Posted October 13, 2011 I think i may have figured out the problem. For high altitude riding during the summer 6500'-1100' I have to run the air screw at about 1 3/4 to 2 turns out. During the winter i have to set the air screw out to 2 1/4 to 2 1/2 turns out. I opened it a 1/2 turn the last time i rode it due to cold weather. Today after cleaning it i ran the engine to dry it out and decided to wind the air screw in and count the turns. I found it set at 2 turns out. I opened it another 1/2 turn and the engine smoothed out at low RPM and the throttle became a little bit more crisp. Somehow i lost track of where it was set or Maybe one of my riding buddys turned it? Now I am getting a headache! First Billy, now you! For a given altitude, a lowering of temps would create a higher air density, therefore requiering the airscrew opening to be reduced(or fuel screw increased) in an effort to attain the same mixture for the engine(same jets). You gotta ritchen the mix that the denser air has created. Quote Link to comment Share on other sites More sharing options...
copemech Posted October 13, 2011 Report Share Posted October 13, 2011 The bike in question is a Beta? Are there any Beta Rev3/Evo owners out there who can confirm that the plug fouling is a prelude to ignition failure? I hope that 'The Right Reverend B40RT' is more right than I am . I think possibly so, more due to misfire than anythin else! Quote Link to comment Share on other sites More sharing options...
billyt Posted October 13, 2011 Report Share Posted October 13, 2011 Now I am getting a headache! First Billy, now you! For a given altitude, a lowering of temps would create a higher air density, therefore requiering the airscrew opening to be reduced(or fuel screw increased) in an effort to attain the same mixture for the engine(same jets). You gotta ritchen the mix that the denser air has created. Why the hell am I giving you a headache? I do agree I am confused why Livlob is making it leaner in colder temps! Is there something we are missing in the translation here? The air is getting colder so turn the air screw in, the air is thinner up higher needing the air screw to be turned out more but only if it is warm and it is not in Colorado right now. I agree with Hank oops I mean Cope................. Quote Link to comment Share on other sites More sharing options...
billyt Posted October 13, 2011 Report Share Posted October 13, 2011 I think possibly so, more due to misfire than anythin else! I mentioned to Livlob to check for a missfire? Quote Link to comment Share on other sites More sharing options...
copemech Posted October 13, 2011 Report Share Posted October 13, 2011 (edited) Jon must be reeling by now after a take at Billys rambling prose! There within, I find good and bad points. My basic farmboy take is simple, and does not disagree with some of his points. Firstly, IS the system optimized by the factory settings? Or is this simply a conservative reliable setting that may be used for the sake of whatever lack of problems. Engineers tend to build up to a point, then back down for reliability in productiion. Second , The range on preffered gap settings as stated by Lovio is quite wide. (theory still suggests that he can push the gap up under his lower density conditions, providing the mix is not too lean) Thirdly, Going along with the first statement, I will admit that I have been somewhat conservative in my personal experimentation, for some obvious reasons, yet the(my) results seem to be reliable and working(at .028 plug gap) so the system has thus far supported it without issue for several years now.. Within common ignition theory , one will find two common issues, gap and duration of fireing. Both provide better exposure to the combustion gass moving within the chamber as the mixture must be exposed to the electrical ionization to ignite it properly. The system will either reliably support the gap and or duration, or it will not, all mostly depending upon ultimate load imposed upon the arc. Throttle openings and mixtures come into play. Then we get into another potential issue here within system design, and to be honest, I do not really and totally know what we are dealing with. They call these things a digital CDI in some or most cases, although I must admit the fact that neither I or many have no idea just exactly what is in these little boxes that actually control things. Seems there is little out there, and although I would somewhat compare it all to a lawnmower with an electronic ignition, functonal testing seems nil via conventional means. The things are reported to have a timing curve to them, so they must be somehow manipulated by the electrics. As an example I use the Leonelly basic diagram used in the Sherco which suggests 2 charge coils and 3 hall effects to run it! Are they charging caps? Very possible. Now within all that, I may fathom it being true CDI, but being CDI in itself it is also limited to the spark dration limitations inherent in the system, and thusly there is a quick voltage dump through the primary coil and a resultant burn time of about 1 ms which is not altered by the demands of gap requirement, it is either achieved or not all in one quick shot by the capacitive dump. Ones gap being the last resort in achiving the best flamefront exposure possible, which should be open and exposed as you do not have a second chance here. Edited October 13, 2011 by copemech Quote Link to comment Share on other sites More sharing options...
copemech Posted October 13, 2011 Report Share Posted October 13, 2011 (edited) And I hope Billy does not go round trying to light fires with his little UV light sabre! Edited October 13, 2011 by copemech Quote Link to comment Share on other sites More sharing options...
copemech Posted October 13, 2011 Report Share Posted October 13, 2011 One thing here Billy, "It is basically matching the gap to get the best out of the mags ability. Simple so far? BUT here is where the crazy part comes in to play. The bigger the gap (within the effective range of the mags output) in other words widening the gap at the widest part of its effective range will afford a spark that is longer in duration," Within a conventional system, it will require more of the stored coil energy to iniate the spark on the wider gap, thus reducing the duration in that cycle as energy is depleted early on. Quote Link to comment Share on other sites More sharing options...
billyt Posted October 13, 2011 Report Share Posted October 13, 2011 And I hope Billy does not go round trying to light fires with his little UV light sabre! Mr Hill......... I will stick my little UV wand up yer a*** and set fire to your propane tank Quote Link to comment Share on other sites More sharing options...
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