This was a tough decision to decide on. I generally stay behind the scenes keeping this site chugging along. Joe, is the one that gives out the amazing wealth of knowledge he has. I've put an amazing amount of time into the bringing together this website and not to mention have footed the bills a few times. I've kept us hacker free for a damn long time. I never ask much of you guy/gals. Only if we get in crunch time and the site needs a little help. Ive never asked for the ridiculous thousands I have seen another site ask for.. ridiculous is the perfect word. I even removed ads for those that log in, severely cutting revenue. Sites been about helping people, not making money. I feel bad actually doing this.. but I need help. I have gastroparesis brought on from diabetes(20+ years). I've been struggling with this nightmare for over 3 years. Finally diagnosed beginning this year. Look it up. Look up worst cases... that's me. Ive lost 60 lbs since January. 28 days ago the company I've worked for for many years found their dirty lil way to fire me. I was approved for up to 3 days off a week for fmla.. that really pissed them off. So illegally fired, savings drained from medical bills, bad diabetic now with no insurance. I'm in deep shit. That is politely saying it unfortunately. If any of you guys cant help please at least keep me in your thoughts. If this was wrong, me asking for help, my apologies. I'm declining in health fast, and unemployment hasn't came through yet and that in itself is a nightmare. Anyone who can, please donate to the website. This time it goes to help me. Thank you everyone. Again, my apologies for asking. I honestly don't know what to do or where to turn.
Rob *This message can be dismissed by hovering over the upper right corner of it and X should appear. click that.*
UPDATE: THERE HAS ALREADY BEEN A FEW OF YOU DONATING. THANK YOU SO MUCH, I'M LITERALLY IN TEARS AS I TYPE THIS. EVERY PENNY COUNTS. THANK YOU SO MUCH FOR BEING THE HEROES RIGHT NOW.
Deceleration Backfiring
Below are actual problems submitted by Virago Owners and Club members. Read through them and see which one matches your particular problem. Feel free to send-in your problem solving experience.
Situation #1 I am a new member of the VOC and need some advice on a problem my 1992 750 cc is having. In the two and a half years I have owned it (bought new) I have enjoyed almost every one of the 39,000 miles I've put on it. But in the last 4,000 miles it has a tendency to do a compression backfire when I have been holding the throttle at a steady pace and then let off fairly fast. It doesn't do it all the time, so when it does it startles me. It sounds just like a rifle shot. I have taken it to the shop. My mechanic readjusted the carbs saying that they can't be adjusted out anymore Next time they will need to be replaced. It is still backfiring. He now says that it probably needs a new "emission valve. Has anyone else had this problem, and what all does it take to change one or do you think that it might be something else? My husband does minor work on our bikes and would do it for me if it would not involve pulling the whole engine. (The Answer as scanned from the VOC Newsletter Mar/Apr '95) IN REGARD TO THE COMPRESSION BACKFIRING PROBLEM WHEN DE-ACCELERATING, I THINK I MAY HAVE A CURE. A COMBINATION OF INSTALLING HIGH QUALITY SPARK PLUGS (SUCH AS SPLIT FIRE) GAPPED METICULOUSLY, CLEANING THE PLUGS AND CHECKING THE GAP EVERY 1,000 MILES, AND USING AN OCTANE IMPROVER IN THE GAS HAS VIRTUALLY ELIMINATED MY PROBLEM. I SAY VIRTUALLY ELIMINATED AS I WILL STILL BACKFIRE WHEN QUICKLY BACKING OFF THE GAS IF I'M AT HIGH ALTITUDE. MOUNTAIN ROADS ABOVE 7,000 FEET ARE STILL A PROBLEM BUT THIS IS UNDER-STANDABLE WITH THE THINNER AIR AT ALTITUDE. Since the publishing of this recommended fix, several other members have asked for solutions to backfiring problems. Following are some of the added recommended fixes and actual solutions: In general, backfiring on deceleration (as opposed to acceleration) is generally caused by a lean condition in the pilot circuit. What happens is that the mixture leans out enough to where is fails to ignite consistenty. This, in turn allows some unburnt fuel to get into the exhaust pipes. Then when the engine does fire, these unburnt gasses are ignited in the exhaust pipe, causing the backfire. Newer Virago carbs have an 'enricher circuit' which cuts in on deceleration to help this problem. Earlier carbs don' have this. I would say check the pilot circuits, and set them a bit richer. It is hard to do this right without some equipment to test where you are. Aftermarket pipes often increase backfiring, probably because they may the bike run leaner. Some backfiring on older modles is par for the course, so these owners should learn to enjoy it. Situation #2 As of yesterday, the backfiring problem has been resolved. Guess what it was......the spark plugs! When I had the 600 mile service, the dealer installed short-reach plugs. The XV1100 takes long-reach plugs. Can you believe it!! Happy now, although a bit dishearted about the dealer....Joe Addison. Situation #3 Found out that the problems that cause the backfire are definitely located in the area of the emission system (air induction system). The air induction valve is the culprit. This is an expensive item. The mixture control valve, which is made of plastic runs $83.00 here in Wichita Falls. In Ft. Worth, $127.00. However, it was working ok. The problem is the air induction valve which is made of some kind of metal. The cheapest solution is to by pass the emission system. This is done by blocking off the the vacuum line from the reed valve to the air induction valve. A local motorcycle mechanic stated that he does this quite often by placing a thimbel in the line between those two valves. He stated that the thimbel is the right size and is cheap. I tried it and it worked. The backfire is gone, the engine runs fine and the spark plugs are the color they are supposed to be. The temperature here today was 105 degrees with a heat index of 110 degrees. I was afraid at first that the mixture was going to be too lean. The bike ran fine. This worked for the 1984 and 1985 XV1000, it should work for the other bikes as well. The Clymer Yamaha manual for XV535-1100 Virago 1981-1995 displays the air induction system on pages 138-139. Good luck with it, Rick Situation #3 I own a 1983 virago xv920k with which I have had the decel backfire problem. The mixture control valve works exactly like a flush valve for a commercial toilet! Intake manifold vacuum acts on a diaphragm which in turn actuates a plunger allowing air to be inducted into the front #2 cylinder. This causes a drop in vacuum and would allow the plunger to immediately close the system to air induction were it not for the fact that there is a small orifice separating the high vacuum chamber (which actuated the plunger) from the now lowered intake manifold vacuum. This orifice slowly allows air to equalize the pressure/vacuum on both sides of the plunger diaphragm and closes the intake manifold to air induction.
Situation #3 I don't care how good a rider you are, how cautious you are, or how long you have been riding. Still, simple, stupid things do occur. Situation #3 Editor's note: Ted has requested that this information remain proprietary for use by Virago owners only and not to be used for commercial purposes. When it comes to machinery I am a perfectionist. A machine, must be carefully maintained and assembled in order to perform to its full design potential. I own a 1983 Virago XV920K with which I had an annoying and persistent backfire every time I decelerated. Copyright © All Rights Reserved Note: This Tech Article was created from the VOC site data.(Virago Owners Club) |