My bike will not start!

Preventing Backfire on Motorcycle Exhausts ' DoItYourself ...

www.doityourself.com/.../5-tips-to-preventing-backfire-on-motorcycle-e...

When the engine on your motorcycle has an emission system malfunction, such as anexhaust leak or a moment of running rich or running lean, backfire can ...

Exhaust backfire, popping when letting off throttle - Motorcycle Forum

www.motorcycleforum.com > ... > General Motorcycle Discussion

Apr 26, 2009 - 28 posts - ‎17 authors
Exhaust backfire, popping when letting off throttle General Motorcycle Discussion. ...You can damage the engine by running too lean or rich. Backfires on deceleration
21 posts
Jan 24, 2015
What causes a bike to back fire?
8 posts
Jul 15, 2012
At my wits end! Backfiring and fouled plugs on ...
13 posts
Feb 26, 2011
More results from www.motorcycleforum.com

Glad That You Asked. Why Do motorcycles Backfire? at Cyril ...

cyrilhuzeblog.com/.../glad-that-you-asked-why-do-motorcycles-backfire...

Jun 12, 2010 - A visible flame may momentarily shoot out of the exhaust pipe. ...Another backfire situation occurs when the engine is running rich, meaning ...

Is backfire when decelerating a bad thing? : motorcycles

check coil to make sure someone hasn't swapped position of plug wires

Reset valves and throttle bodies

check fuel is good and not older than 6mths if bikebeen stood long period ? carbs may need cleaning !

If you change the exhaust pipes, you have to sync the carbs (if you cant sync them, you have to change the carb jets), usually it is backfiring because the carbs are not in balance.

KICK HARDER TRY PULL STARTING IT..IN SECOND GEAR..DOES IT HAVE ENOUGH COMPRESSION TO START?IT SHOULD START PULLING IT...START OFF WITH NO THROTTLE THAN IF NOT STARTING CRACK THE THROTTLE SO LIGHTLY AND SHE SHOULD FIRE OFF WHILE IN GEAR BEING PULLED OF COURSE BE CARE FUL NOT TO RUN INTO. WHO EVERS PULLING YOU..USE A LONG TOW ROPE..IF YOUR NOT A SEASONDED RIDER AND KNOW YOUR BIKE VERY WELL I WOULD NOT ATTEMPT THE PULL START...IF NOT CHECK YOUR COMPRESSION AND TIMING..MAJOR VACUUM LEAK MAYBE AT BASE GASKET..IS ENGINE SUCKING TO MUCH AIR? GOOD LUCK..

it probably isnt a firing order problem, or it probably wouldnt run

one coil fires 1 & 4 cylnder, the other coil fires 2 & 3 cylnders, as the pick up gets its signal from the crank, it sends a spark to each cylnder on the exhaust stroke as well as the compression stroke, ignition timing also doesent change as it is electronic and cant drift out like when points wear.
a short in the ingnition or kill switch can occasionally cause a backfire
Backfire can also be caused by
lean mixture, dirty carbs, loose carb clamps
leaking inlet or exhaust flanges and gaskets
tight valve clearances, burnt valves

make sure everthing is clean and tight, good air filter and exhaust, check valve clearances ,and give it a compression test, check the valve timing, incase it has been assembled wrong,(they rarely jump a tooth unless the chain and tensioner are completely stuffed)

u need clymer manuals for both bikes--library has a vehicle troublshoot section also

that sounds like a timing issue with the back fire, also check coil wires.

Next time this happens, take out 1 spark plug and inject a little gas, replace the plug. (You can do both f you want but 1 is enough) If the bike fires up it is prob not getting gas for some reason…