a mates fx shovel was misfiring on the rear cylinder.pulled both plugs and looked good even had a second opinion.so just out of curiosity replaced the rear plug and all is good. has anyone come across that before thanks

 

plenty of times...treat your plugs with kid gloves...dont drop em

 

only had this with champion spark plugs
especially the rear cylinder the first one to go
because it run hotter

 

 

was champion plugs

 

Never had a problem with Champions... In fact About the only Plug that will recover from wet fouling is a Champion... NGK??? Forget it.
Found many times that the Squirter is pointed at one cylinder or another ... an a Throttle Jockey can foul the cylinder being Squirted... Just sayin..
BTW As a matter of fact..., While riding.. The rear runs Cooler... Check for yerself..
Know Why???
Flame on!!!!

 

your gonna be told by the pros on here that the "front" cylinder is the one that runs hotter- and I agree---

 

I can vouch for that....after I replaced my fairly new AC Delco with new NGK and setting idle, I couldn't start the bike. Cleaned the NGK and still could not start. Removed the NGK and replaced with new AC Delco and started right up. NGK no more.

 

well the front cylinder is hotter TO ME for a couple of reasons

1 its out of the way in the oil spray from the flywheels unlike the rear

2 the pull of the machine as its going forward the intake mixture is heavy latent with fuel this causes it to lean out - But if you tilt the carb to the rear a few degrees that goes away just like the XL factory 2 carb race bikes the carbs angled to the rear - on a dyno we looked at that and the egt did fall off ( went rich ) with the angle - but then the rear didn't like it

 

wow I don't get it the front cylinder catches the fresh air first
how can it be hotter and why Harley designed a device for
putting air on the rear cylinder it fits on the dressers I'm sure
somebody here has one