Hey guys, Im having some trouble with my 1988 flhs. It will run just fine while cold and will idle in my garage indefinitely, but as soon as it gets up to 125-150 degrees the tach goes haywire and the bike will sputter and die. From my limited experience that usually means the coil housing is cracked and as it heats up it will quit working, but the housing seems intact. Also from time to time when I pull the clutch lever the tach will go crazy and Ill lose all power including lights for about a second, then everything will return to normal. Im not sure if I have two separate issues here, is there something that could cause both of those things? My mechanical knowledge is fairly limited, so any and all help is greatly appreciated.
-Jem

 

If it were mine i would start the bike after it sat for a bit and is cold. Then take a heatgun and heat up the coil to see if it replicates your issue. If not the coil then i would put some heat on the cam sensor in the nosecone. Those tend to go bad and only show it when the bike is hot.

 

No dice on either of those. I let the bike cool down and just had it idle, couldn't get it to die buy heating either the coil or cam sensor.

 

Has it happened at any other times? How sure are you its a heat related issue? That clutch issue is stumping me at the moment.

 

Im only guessing its heat related because it dies when Ive been revving it, but when it cools down will start again no problem. The first time I noticed the clutch issue was about two weeks ago, I was riding in the evening and noticed my headlight would cut out when I pulled the clutch. Shortly after it started to lose all power, but would return shortly after I let the clutch go. I rode it several times after that with no issue at all, then last week I was on the freeway and it completely died and would not restart. I let it sit for about five minutes and it fired right up, but only ran for about a minute and died again. Now in my garage it will idle fine but if I rev it up to around 2500rpm it will die after about a minute.

 

Clutch issue sounds like a pinched or bad wire in the right handlebar controls. Probably unrelated just a wire issue, when you pull the cluch it shorts to ground release it goes back to normal.

 

The clutch lever is outside the switch housing, there is nothing to do with the clutch in the housing.

OP: inspect the wire from the starter to the main breaker, and from the main breaker to the ignition switch.

Replace the main breaker.

 

I know clutch lever is outside of the switch housing, the clutch lever clamp goes across the wires though and the clutch clamp holds the switch housing still as well. So like I said could be a pinched wire issue and if the wire is not routed appropriately through the clutch lever clamp then when you pull the clutch you put pressure on the wire wich would cause all kinds of funky effects.

 

i had something like that happen to my 85. tach would go nuts, i found the underside of the voltage regulator had a crack in the sealant. on a machine that old i would replace the main 30 amp and all 15 amp breakers as well.