1980 FLH 1200 stutter

[David Gilmore]

Got an issue with a slight sputter that seems to appear just before I shift into the next gear.
We've checked the electronic ignition, adjusted the lifters, replaced the ignition switch, cleaned the carb, sealed the intake, cleaned the petcock screen.
The bike will run fine at times with no sputter, then after a stop and rest , it may start up again. I can bypass the stutter by accelerating but if I maintain a steady 55 mph, it will act up occasionally.

Sometimes the stutter is slight but other times it may be more intense.

The bike ran fine last season but around Sept. it began running rough. I ended up with a stuck valve and replaced all 4 lifters and rods this spring. Still can't find the source of the stutter and it's driving me nuts!!
Getting a lot of other things fixed though!!....

The bike starts and idles fine.

 

[Jack Klarich]

Welcome to The Forum, What kind of carb? Check the coil, spray some water on it see if it misses, check the wire coming out of the cone for pinches and burn marks The control modules for early electronic ignitions were famous for this as the engine reaches temperature

 

[David Gilmore]

Thanks!
It's a Keihn carb.
I've checked the cone and haven't found any pinched or burnt wires.
Going to check the coil as you suggested in a few minutes.

 

[David Gilmore]

Sprayed the coil with water...no change. Sprayed the wires running out of the coil...no change.

When I took it down the road, it sounds like it is not getting enough gas/spark
so I'm going to check the diaphragm on the carb.

The bright side is....I'm getting a lot of new parts and other little issues fixed along the way!....lol

 

[garystrat]

try the next bigger main jet
Ps HD went to 80 cid in mid 79

 

[David Gilmore]

Thanks, going to look at that now.

Yes, this shovel is a 74 though, 4 speed Electra Glide.

 

[Jack Klarich]

Have you checked the Battery connections this is a link for the charging system http://www.hdtimeline.com/archive/t-47714.html

 

[tourbox]

Also check your automatic advance unit.They were still mechanical back then.It could be sticking are worn out.
tourbox

 

[Jack Klarich]

Also check your automatic advance unit.They were still mechanical back then.It could be sticking are worn out.
tourbox

That is a very good point, check the roll pin on the back of the mechanism, seems to me I remember them wearing and shearing, this could lead to a no start

 

[David Gilmore]

Thanks guys!!
I'll let you know what I find.