Boggin' in the rain!

[Scudder]

I ride my 1980 gs850 as a computer daily about 50 miles a day. Since the weather has warmed some in Chicagoland over the past couple weeks I've been riding nearly daily.

The bike is great a runs well, and I'm normally very happy with everything about the bike. However, It rained quite a bit today when I was at work. Bike started fine after work, but is was bogging down or cutting out a bit on the ride home.

On the expressway it was raining pretty good, and I had a hard time getting it up to 65-70 as easily as normal on a dry day. It eventually got up to speed but the quick acceleration was gone at speed. After I got off on the exit ramps and was stopped at a light, the bike seem to pick up better and didn't have any issues.

Any ideas?

Scudder

[matt1100]

Mine runs crappy in the rain too, could be they just don't like getting wet. My theory is that the extreme amount of moisture in the air throws off the air fuel mixture and is compounded by ethanol's reaction to moisture. There is one place in my area that sells 89 octane "marine" gas, which is pure gasoline. I should use it more often

[Scudder]

Air flow issues makes sense. I rode my old bobber from Milwaukee, in a down pour a couple years ago. I put an after market air filter on it which allowed small amounts of water to be sucked into the carb. It was cutting out much like tonight.

I sure would like to find out a way to prevent this on my gs however.

thanks

scudder

[bonanzadave]

If you have not ever changed the spark plug boots.....change them NOW.

It is cheap insurance that prevents arching in wet weather.

http://www.bikebandit.com/ngk-plug-caps

[Steve]

A couple of things come to mind:

1. You running pods?
1a. Are they cheap paper ones or are they good ones (K&N, APE, Uni)?

2. You still have the original plug wires (and/or boots, as bonanzedave suggested?

To see if it might be the wires, stop beside the side of the road, leave the bike running, make sure it's on the side stand.
Run your fingers along the wires. If the problem is that the wires are getting wet, YOU WILL KNOW IT REAL SOON.

.

[Scudder]

I'm not running pods. I changed out the plug caps last summer, but haven't changed the wires. It's not supposed to rain to day. I am riding to work so I'm hoping things are good when its dry. That will at least mean, in my mind anyways, that it is rain related, and narrow the path to figuring it out.

Scudder

[Scudder]

OK. Just finished my morning commute, which was a dry one today. The bike ran like normal. On the expressway, I barried the needle on the 85mph speedometer rather quickly today just to make sure the acceleration and top end was still there. It is.

I did notice the idle at stop lights was lower than normal. Maybe just a coincidence, but could the cutting out in the rain, and drop in idle be related to an electrical issue? I did replace the stater and R/R this Winter, but I know they wouldn't necessary be contributing to this type of problem.

The new plug caps I put on are transparent so I can see the plugs and wires are doing their job.

Normally not too big of an issue to deal with this and figure it out over time, but I'm riding this bike to the Smokey Mountians in 6 weeks and would hate to have a reoccurance if we run into rain.

PS: I have riden this bike in the rain plenty times before without a problem. Could the new tranparent caps be the issue?

Scudder

[Steel Toed Tank]

I had my bike start doing this same thing way way out in the middle of nowhere.
I hit a patch of bad rain and instead of being able to power up to 150km/h+ is seemed to take all the bike had to maintain 100. Once clear of the rain I could feel the bike switch between full power and not full power.
It did this off an on for a little bit then cleared up all together once the bike was dry.

To combat this I used quality electrical tape around where the plug wires meet the cap, and I stuffed the caps full of dielectric grease.

Never had the problem again.

[Scudder]

Thanks I'll tape them tonight.

Scudder

[Steve]

You can also spray the wires with WD-40.

Yep, go ahead and use the stuff the way it was intended.

.

[Scudder]

I check my plug wires. No cracking, etc. Could it be that the new caps are letting water in? Seems that plug wires are to only possibility?

Scudder