Hi, my 1984 FLHT slowly started backfiring during down shifting, It's got to the point that it won't start now. Any ideas Thanks

 

It's hard for me to guess without seeing the bike, but first thing I would check is timing. If the exhaust valve is open too long and the intake is allowing fuel/air in you could be getting detonation in the exhaust pipe. May be a cam, chain, or a valve problem. Do a compression and leak down test. Good luck.

 

Definately sounds valve/Timing related.... Did you have a sudden shut off before it died completely......If so- possible internal breakage (chain, etc.)

BRUCE

 

Check the intake manifold gaskets! I melted a gasket crossing AZ in 113 degree heat....easy fix if that's the case...spray some starter fluid on the intake gasket seal and if it dies...there ya go!

 

Thanks for the advise so far, I checked the compresson and #1 and 2, they were at 115. The carb has a back residue as so do the plugs.

 

Was the bike starting and running good, except for the backfire on decel or were there any other problems, before the bike would'nt start? It may be something as simple as fouled plugs.

 

Sounds like a rich (fat) running condition,, and more than likely fouled the plugs. I would check the slide needle in the carb to make sure it is properly seated in the diaphram. Keep us posted.

 

Did you, by any chance, fuel up anyplace different lately?

A few years ago in WV, I picked up a tank full of "slop gas"...gas that was mixed with diesel fuel...the scoot smoked a lot and fouled the plugs and messed up the flaot bowl and jets. Just another possibility.........

 

I've owned it about a month and road about 50 miles total, the guy a brought it from said it was filled with gas last during the summer, so the last 10 miles I put stabo in with a full tank.

 

I would drop a new set of plugs in it right off the bat, and ck the plug wires; easiest to ck at night - see if there's a light show going on, otherwise a meter is needed if there isn't an obvious problem. Next I would ck over the general tune condition (fuel filter, timing, carb, etc.)