Only runing on 2 cyls?

[mpoertner]

Hello there! New to the forum. Does anyone have a digital copy of the owners manual? That might answer a lot of my questions about this bike. I bought my 83' Venture Royale a couple months ago for $900. I have lots of questions but one major one concerning me right now.

 

I don't know the bikes history so I was doing some routine maintenance on it. Replacing spark plugs and I noticed the plugs were wet on 2 of the 4 cyls. So I started up the bike and sure enough - If I pull the plug wire from those same cyls the engine does not bog down at all. While if I pull the wires from the other 2, the bike just about dies. There is spark on all fours wires though. And if its wet with fuel and getting spark, what gives?

 

If it matters - the cylendars in question are the front left and the rear right.

 

So is the bike really only running on 2 cylinders? Hell, I thought it was running fine. Theres not enough power to pop a wheely like another gentleman mentioned in another thread but once warmed up the bike runs smooth and has been a great commuter for the past month or so.

 

Any help would be greatly appreciated.

Matt

[mbrood]

Sounds like the carbs are simply out of sync and two are pumping too rich... I would start there. Even a look down into the carb throats should show all butterflies closed an equal amount and they should rotate open equally as well but a vacuum sync sounds to be in order.

[bongobobny]

Check the vent lines for the fuel bowls, they may be plugged. Also even though you have spark it may be weak, get a spark tester and measure the maximum distance, it should be at least 0.070".

[Venturous Randy]

Also, pull the sided covers off the carbs and check the diaphragms for pin holes or being torn. Bad diaphragms will cause plugs to foul. Just remove the four screws and lift off the cover. One screw may have a safety screw and if you don't have a socket to fit it, you can usually use vise grips.

RandyA

[mpoertner]

Great ideas everyone. Thanks! When I get a chance to check these I will report back with what I find.

[dacheedah]

http://www.yamahaventure.nl/en/motorcyclemaintenance.html

[van avery]

http://labs.trunkful.com/vrmanuals/index.cfm

Service manual if you don't have.

[buddy]

Mine was doing this as well so it may not be it? but doesn't hurt to check

remove left side cover on upper frame rail just under seat by the false fuel tank area you will see a white 4 wire pig tail this is your pickup coils mine was not getting good connection causing issues