Help a brotha out!

[tradrockrat]

I'm stuck. I'll list the issues and then I'll tell you what it IS NOT.

2006 RK Custom damn near stock - PCIII and Screaming Eagle slip-ons and air filter. Around 40K miles

Excessive noise / vibration from bike - sounds like knocking engine or top end clatter
Cracked Rear Exhaust pipe
Two killed batteries in less than a month

Front motor mount is perfect.
Top motor mount is perfect.
good ground to regulator / rectifier, but am unable to test current because battery is dead

I was assuming bad front motor mount and bad rectifier - but now I'm lost. And I'm WAY too broke to throw new parts at it until it stops breaking stuff. Even assuming the rectifier IS bad - which is the most likely culprit for the batteries - I'm not going to replace it if I can't figure out whats shaking my bike apart and breaking it.

The bike has been down almost a month now and it's killing me!

any way to test the rectifier off the bike?

Help! Beth wants to ride and we don't fit on a 500cc single!

[GzrGldGeo]

How about the stator? Maybe it has a mechanical (vibrating, knocking) and an electrical not charging battery properly too much or not enough. Maybe the stator and regulator to start. You think you have 1 or 2 problems?

With the bike off and positive disconnected does the positive measure anything less than infinite resistance (total open). If this is the slightest resistance that can be measured there is some type of short I would think.

That is about all I can offer. I don;t know shit. Can you take out the power commander, just to make sure it hasn't went haywire? No telling what a haywire Power Commander might do.

[speed]

George's last suggestion is a good one. I have seen more than my fair share of Power Commanders go bad. Try running the bike without it plugged it.

If that doesn't fix the problem are you sure the roughness is an electrical problem? You need three things to make power; compression, fuel and fire. Have you done a compression test? Have you checked the plugs for an even burn on both cylinders?

With regards to compression - did you have a backfire at some point that could have taken out a valve? If you have a loss of compression it's more likely in the heads than the rings and cylinders on a bike that's only a few years old.

With regards to fuel delivery - did you have a backfire at some point that could have taken out your intake gasket on one cylinder and is leaning it out? That would be the most common culprit for a lean condition that would cause a very rough running engine.

If you have access to another RK I would try swapping the crank sensor out too. They seem to go on a regular basis. I just replaced my third on my RK and when they go you'll get a very rough running condition.

Good luck.

Cheers,
Speed

[Blackpearlultra]

I am wondering if you have an intermitent short to ground? It could be causing your bike to fire out of sequence which would shake the shit out of it and also kill your battery. Have you had any work done where a wire may have been pinched?

[tradrockrat]

Thanks for the replies -

I used a sporty battery to run a test for a ground and didn't find one. I'm gonna try to start the bike with a jump and the old RK battery in a bit and test voltage at around 3000RPM - if it's right (I hope it isn't so i can replace the regulator and have the electrical issue "solved") but still running rough I'll pull the PCIII and try it without.

I think I may have two separate problems - I'll try to fix on at a time here.

[tradrockrat]

Update

Found an old sportster battery that can crank over and start the bike

Tested voltage - 14.8 volts across the rev spectrum, from idle to high revs (no tach). Apparently rectifier/regulator is fine. Also seems to indicate that stator is good

Replaced front motor mount anyway cause I had one.

Rear exhaust bracket is broken

Unplugged PCIII - no noticeable change in engine noise.

After sitting for near a month I got black smoke out of right exhaust pipe when reving.

Noise seems (and I mean seems - we all know how sounds can be tracking nightmares) to be located in front cylinder. Knocking continues after shutting off as engine winds down. you know - kind of a knock related to piston / flywheel / primary movement

Shaking seems to be under control?

New questions:

If regulator is good and there is no apparent short / ground what the hell killed my batteries?

Did the rear bracket brake and then cause rear pipe to break or did something else brake them both?

Is the knocking and the black smoke related or is the smoke just a result of sitting for a month?

oh yeah- - managed a newbie moment and set my arm against my pipe while changing out the PCIII - the hot pipe... left a dime size layer of skin behind - youch!

[speed]

The front motor mounts from Harley are junk. Hopefully the new one has solved your shaking problem. When the front mount breaks down (usually from oil being dripped on them) you can get enough engine shake to break pipes and pipe mounts. Been there done that - especially with the old style Rinehart True Duals.

Good luck.

Cheers,
Speed

[tradrockrat]

Thanks for all the input - I'm taking tomorrow off to track all this down and at least figure out the issues. Any more input is always appreciated.

Now it's off for more electrical testing...

[RamMedic]

Did you ever do a compression test of both cylinders?