Back fire

busanewb

Registered
Today I started up the bike. It had been sitting for a couple months and one of my friends said I should press the starter a couple of times to get the oil circulating before actually starting it. After pressing the starter 3 times I got a loud back fire out of the exhaust. Bike started up when I pressed the starter again. Should I not do that? I'm assuming I either over fueled the motor or compression got to high. Do you think any damage was done? I'm not too sure what to do when I do leave the bike sitting for either winter storage or just don't have time to ride... I'm assuming the motor is pretty dry so start up is harsh
 
Start up is harsh no matter how long it sits. Dry is dry. What you'd like is oiled cylinders before firing up. Wouldn't we all. I doubt that spinning the motor w/o starting it would provide enough oil to the cylinders to make any difference. Not sure why it back fired. The engine management system should prevent over fueling as you put it. I rotate riding between bikes so one always sits. There are several things to know about letting a bike sit for long periods of time. If you follow those guidelines everything will be fine when you want to ride it. If you need some info just ask.
 
what would you recommend for starting? I usually put fresh gas in the bike and check to see if the battery is charged as well as check tire pressures.
 
Years ago... with my first motorcycle I had... a 1982 Kawasaki 440 ltd.... I would pull the plugs and drop 4 drops of oil in each cylinder for the wintertime storage... not sure if it helped anything.. I haven't done that with any bike in years and years though... just start the bike and DONT REV IT.. let it idle for a couple minutes... ride it and warm it up.. there are many different metals in an engine and they ALL expand at different rates... until the engine metals are done expanding and the engine is at (more or less) running temperature...
 
Bumping it like you did prolly made the motor back up a bit from the cylinder pressure and it backfired by the open valve. This is obviously not "good" for it but you most likely didn't harm anything just once.
If you really want to do that (preoil) then pull the spark plug wires and just hit the starter for 10 seconds then reconnect and start as you normally do.
If you want to be worry free just run synthetic oil like Amsoil and it will protect better even when left sitting because of the superior sheer wall strength.
 
This is what happens to my 14 after every winter storage. What I do to not let it happen is don't start the bike until the weather is warm. At least 50 degrees F and let it sit in the sun a few hours. Also, have the battery fully charged. I beleive I got a backfire from the busa once too.

If you oil your cylinders before storage and turn the motor by hand one revolution to coat the cylinders, you will also oil your spark plugs. The plugs may foul when the motor lights. I would only fog the engine if the bike was going to be stored years, not months but if you want to go through the trouble, put in a set of old plugs for the first start and then change them out for the good ones again after it runs a few times for the season. See if the startup plugs look greasy.
 
I agree that fogging is for loooong time storage not just over the winter. Mythos is right about the plugs too. Mine are always parked on tenders, have full fuel tanks and I mix in a little Seafoam and run it so it's present in the fuel tank, lines, carbs and injectors. I also run Amsoil. Good stuff! I've done this for years on several bikes and have never had to change plugs, buy a new battery or have my carbs (6 of them on the 39 yr old CBX) or injectors cleaned.
 
+1 on the Seafoam. It's been around for ever (I heard about it 40 years ago and it was well known even then) and has always been highly regarded for moisture elimination fuel stabilization and it definitely cleans the fuel system so do not overdose it. It is pretty strong. I use a a smaller dose about every other fill or so during the riding season too. 1 oz/gallon for storage. Use only in the fuel system for bikes. Not in crankcase.
 
My mind is blown.
Do you guys really go to all that trouble just after a couple of months not running?
My bike sits in the garage over winter (and we get snow for a week or so here in Darfs NZ) and all i've ever done is kept the battery fully charged using a tender, and when I'm ready to ride I crank it over and it starts right away.
No fuss, no hassles, after all, it IS a Suzuki with legendary reliability! :bowdown:
I let it run at a fast idle (2000rpm) for a minute or so, let the idle run at 1200rpm for another few minutes while I get my helmet and gloves on, and then it's 'Hi Oh Silver',
or blue and white in my case.
Everyone has their own way of doing stuff I guess, who's right or wrong is hard to guess.
 
Mine is stored for 5 months each year. I don't know how much harm would come from doing nothing at all but I do it every year for peace of mind. I'm not sure I would bother with the whole routine for two months. The bikes have sat that long in summer. I'd at least check antifreeze strength.
 
I called a friend who is a ducati technician. He said it was most likely unburned fuel that got in the exhaust and one of the cylinders sparked it. Sound right?
 
There should be no spark at all when the valves are open but who knows---? Maybe if the fire in the motor could last all the way to the exhaust stroke??? Seems very possible if there was a bunch of fuel in there. Maybe the backfire then creates so much backpressure it can stop the engine instead of letting it run. IDK. Food for thought.
 
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