I am having two issues with my Hog, and I don't know if they are connected or not. I would appreciate any comments.
1. Electrical problems: power failures and the battery dying twice.
2. Sometimes idles fine, other times she kind of fakes to stall or stalls at the light, but more like a general 'stumble' (best description I can think of); sometimes this stumble happens in higher gears, like a temporary 'lull' as you are cruising (as if the bike thinks it is empty then realizes it is not).

Could these two issues be connected? Could some electrical issue (stemming from the stator/regulator/Rotor/current/voltage) also manifest in an unreliable idle and/or little lulls in power (for instance, second gear in a 40km/hr zone, brief power loss). Are these two or three separate problems, or one inter-connected problem?

A bit about the bike for context. This is a 1992 FXR, 1340 Evo. She is in good nick in general. I got her a Stage 2 rebuild in Spring 2010 (only had 25,000 km on her when I bought her in Fall 2009): new pistons, mikuni carb, ev27 cam, new ignition and coil and rollers etc etc, V&H big shots. Seems to run like a dream except for starting/battery issues and the idle/lull problem. Problems started last summer: brief power failures (2nd and 5th gear). Battery died last August, and Harley replaced the starter jack shaft kit. Last October she lost power on the freeway (no lights even), and I had her towed to Harley. Battery was not seated properly they said, and the cables/wires had frayed and detached. Reseated the battery and fixed cables. In November she started like a bitch and idle was bad (nursed her at lights). Put her in storage for winter. Got her out today, rode a few hrs, idle was poor and had a few lulls, stopped for 45 mins, would not start (tick tick tick was it!).

I apologize for not being as mechanically competent as I should be for riding this old beast. I'm now trying to understand if this is separate problems or an inter-connected problem. I am open to all ideas. I will have the Harley stealership that did the Stage 2 look at it, but it seems they did not fix the problem previously, so I need to get up to speed! Sorry for the long post! Any suggestions???

 

Sounds to me like it is a series of problems stemming from one major electrical problem... there are too many tests to list here, but I would recommend NOT taking it back to the HD dealer. Start with your battery... is it fully charged and holding that charge? Then move to the battery with the bike running... 11.7 minimum to 14.8 maximum voltage... any different there is a charging problem. One step after another needs to be done... not hard, but get a hold of a trouble shooting guide for 12 volt electrical systems. Doesn't even have to be bike specific...

 

+1 on battery. Check your voltage before you start the bike. Then, check your voltage as you start the bike(load test). Your voltage should drop as you start the bike but if it is a major drop(8v-10v), you probably have a dead cell. I had this problem a couple of years ago where battery would start the bike and the bike would run, but run like chit(like it was starving for gas).

 

Another place you might look is your intake. If it is leaking it could cause the idle and stumble problems. Easy to check, with engine running spray some carb cleaner around the intake seals if the idle smooths out or goes up you found your problem.

Unless your battery is dead it should not cause any performance problems with a carb. set up.

 

Check the condition of your battery, if it's a wet cell are all the levels up? Check connections. Check voltage across the battery at idle, if idle is too low you are not even replacing the charge, you are drawing power not charging. The sound of a low idle sounds cool but comes with a price. With the engine idling at the proper rpm spray some WD-40 around the intake if the rpm changes, you could have a leak at the intakes.

 

Thanks for the replies.
I started with the first piece of advice. I retrieved the hog from the HD dealer, having told them to charge the battery, and rode it to a performance shop. The bike only just made it, dying at the light two blocks from the shop (the only stop on the way!). I pushed it two blocks. Fun. They are doing a full electrical diagnosis. I will mention to them Tuesday to check the air intake, so thanks for that tip.
In the meantime, the HD dealer has agreed to cover labour costs plus the cost of a battery if it has been killed. My argument was that I had brought the hog to them three times with power failure and idle/stumble issues, and that when I pay $92 an hour for labour cost I should be purchasing competent judgment not trial-and-error mistakes. So aside from replacement parts (like if the stator is gone), The HD dealer will reimburse me labour costs, a battery if it needs replacing, and the cost of the dyno tune HD never did post-Stage2.

I wish the HD dealer was being decent when I brought the bike in for repairs, of course!

 

Many dealers have a hard time keeping good help for various reasons and that leads to poor overall repair. Your issues could be related and I have seen simular issues on carb bikes when the batt is weak. A good indy will get it sorted out as they see many more problems like this than the dealer.