Engine problems in the rain

[rev_mook]

Hey gang, I was riding threw Kansas when the sky opened up into a deep black color and unleashed a fierce thunderstorm.   I decided to push threw, as there was nowhere to stop except for the side of the road.  Unfortunately the machine had a different idea and picked a spot for us; it lost half it's power at speed.  Further investigation revealed that the left side cylinder stopped firing.  After the rain let up I was able to get the engine running okay at higher rpms (3,500~4,000) but at idle, the left cylinder would not fire..  I suspected water got into the carb and somehow screwed with the pilot jet?  I dumped the float bowl and rode a few miles, but this didn't fix it.

At this point the bike was dry, and all the connections seemed dry.  After about 40 miles of riding this morning, the idle returned to normal.

Is this a sign of the HT lead going bad, or perhaps a failing coil?  I can't really troubleshoot on the road, unless it fails to work again...

[Bob_Roller]

If you have the original OEM black and gray coil, check it for cracks .

It usually gives you problems in damp conditions .

A Dyna 'brown' coil is a popular replacement  part .

Your symptoms are classic high voltage side of the ignition system problem .

Replacing the spark plug leads, would be a good idea, if you have no idea how old they are .

[Bob_W]

When my "Crack-o-matic" failed I could see a crack in the coil. When dry it ran great, but not in the rain. For me fifty miles from home on a bike means rain.
Bob

[Bob_Roller]

Don't know if you are on your way back home, or are still trying to get somewhere .

Motorrad Elektrik has the Dyna brown coil and adapter bracket for around $95 plus USPS Priority mail delivery, they also have ignition leads for $25 per set .

Located in the Birmingham, Alabama area, usual 2-3 day delivery time .


http://www.motoelekt.com/ignition.htm

[nhmaf]

Yes, most likely the coil if you have the OEM unit, this is a common symptom of a cracked one (and the cracks may be VERY tiny and hard to see) - another vote for the Dyna Brown coil - and do replace the plug leads while you're at it if they are over 5-6 years old..

[Matt Chapter]

Did I ever tell you guys about the time I took the beemer in to the Honda shop (at the time, they had a duc / beemer mechanic) and they washed the bike after they were done with it?

It took me at least an hour to get it to start, and by then I'd killed the battery so I was pushing it up and down the parking lot!

I replaced the coils with the dyna coils very shortly after that.

[tvrla]

Yep - the coil! My 81 had that problem when I got it. Rode in the rain and it ran crappy.

So if you don't feel like replacing it right away, just don't get it wet!  

[rev_mook]

Just an update:  I got suck in a torrential downpour, luckily under some shelter.  This afforded me some time to swap spark plug wires, and the problem followed!  I limped over to an auto parts store and picked up a universal repair wire, cut it to size and now I can run in the rain.  Today I ride the Tail of the Dragon!

http://goo.gl/maps/aGQ3c

 

[Justin B.]

The Dragon's a blast!  Suraklyn and I did it last summer on the "big bikes" and I'd like to try it someday on an Airhead.

[Bob_Roller]

If you can work US 191 in eastern Aridzona into your route home, you won't be disappointed !!!!!!!!


http://www.motorcycleroads.us/roads/az_us191.html