80 850 troubles

[Anonymous]

I have been trying to get a 1980 850 back to riding shape since I bought it about a month ago. The main problem now is that if you give it any throttle at all it will bog down and die, always. It idles pretty good for being out of synch(havent got a synch tool yet). I have rebuilt the carbs and it runs a little bit better but still the same problem.
Also, cyl 2 is running a lot cooler than the rest and has a miss in it. I changed the plug and switched the 2/3 plug wires and still cyl 2 ran cool. What is going on with my bike???????? I am really really new at all this and need as much help as I can get. this site seems to be amazingly just what I need. I love this bike and want it running proper.Thanks to all who respond.

[Poot]

Well, a carb sync would help (if it was really, really off, it might solve it) and also the adustment of the air-fuel screws on top of the carbs, which should be around 1.5 - 2 turns out.

Are all of your cylinders getting fuel? When My 3rd cylinder was running cold at startup, it was because the float needle valve was stuck closed, and no fuel was going in to the #3 carb. Just check that by unscrewing the float-bowl drain plug, and if fuel starts leaking out as your unscrewing, its probably full.


ALSO , make sure your getting a good spark . test this out, by taking out all of the spark plugs (and then re-attach them to the wires,) and make sure they're near some ground (like the engine block) when you try and start it, check the spark coming out. It should be a nice blue spark.



See how those things go, and some other guys should have posted by then



POOT

[Anonymous]

Thanks for the quick response. I have the air fuel screws adjusted and no real change. Still bogs down. Is there anyway to get the carbs at least a little close to in-synch without the synch tool?
Bowls all have plenty of gas.
There is some juice going to the spark plug but it might be weak. When I take the plug wire off the plug there is no drastic change in performance and my hand gets a nice buzz, hehe, as I hold on the the wire. The exhaust does get get warm but no where as hot as the others.
Thanks again!

[frosty5011]

Chris,

What does the #2 plug look like?

[SqDancerLynn1]

It sounds like you still have carb trouble. YOU must dissamble the carb rack & replace EVERY O ring & have the carbs spotless. NEW intake O rings New boots if needed. Air cleaner MUST be installed with a Good filter
sealed to the housing Side chrome covers sealed to the box NO AIR LEAKS

[Mastiff]

You can do your own carb sync pretty easily. Here is a site that tells you how to make a carb sync tool for just a few bucks. I'd make two of them for our 4-cylinder bikes.

http://www.powerchutes.com/manometer.asp

[mark]

Back to that other question. What color are your spark plugs when you remove them? By the way: Zen and the Art of Motorcycle Maintenance!

[Anonymous]

Wow thanks for all the responses! I got a new plug for cyl 2 and it still looks totally clean. It was black, but since the bike has set up for who knows how many years who knows when that carbon was put on the plugs.
I did, to my complete surprise, come across a great web site about carbs in general giving the mechanics of it all and I figured it had to either be my needle jet or air/fuel needle. I took the carb apart today and there it was, the dirty dirty clogged needle jet that I didnt know to clean or that it even came out. I have lapse in clear thinking and turn into an idiot on occasions.
Anyway, the carbs are on the bike but I cant get gas in the bowls for nothing without cranking the engine for the vacuum to pull the gas in! Is
this normal?
I read Zen and the Art of Motorcycle Maintenance when I was in high school and loved everything about it. It kickstarted my motorcycle love.
thanks everyone.

[frosty5011]

Anyway, the carbs are on the bike but I cant get gas in the bowls for nothing without cranking the engine for the vacuum to pull the gas in! Is
this normal?

If your petcock's prime doesn't want to work (your's probably just has the screwdriver slot on it, as does one of my bikes), then just unplug the vacuum hose where it's connected at the carb and suck on it for about 10 seconds or so to open the vacuum valve and fill your bowls. No gas will come through that hose, or if any does, your petcock needs to be replaced/rebuilt.

[Anonymous]

Just got through getting the bike restarted and the problem still exists. What in the heck is the prob.
Thanks for the advice on getting the fuel back into the bowls that will help a freakin ton, after all I have had to rip apart the carbs three times already.

[jimcor]

So, chris, are you a pianist? Related to the great composer, or just missing a 'p' in your page name?

[Anonymous]

Actually, I am a classical guitarist with a strong affinity for great music, i.e. Chopin.
I have done everything I know and nothing is helping my bike. I have done everything suggested except synch my carbs. I will post a new topic about a carb phenomenon that I have noticed.
thanks to all again!

[Poot]

since you went and rechecked your float-needle valve, I think it may be gumming up a tad. Even after I cleaned mine, and put it back together, they got stuck, and I had to take it apart, and put it together again.



You mentioned that the spark buzzed you. You should se a really nice fat blue spark go from the spark plug, to the metal of your engine when you try and start.



Do you have a compression gauge? Maybe checking the compression could shed some light on the cause?

[mark]

For what its worth, I'll tell you my story with my 79 850. I too was getting erratic spark, miss, coughing, dying, etc. The bike would run on one cylinder, then two, then three, then one, just nuts. Changed everything checked everything I could think of. Turned out to be the spark plugs even though I'd just put in brand new ones. Those plugs if they have been fouled even once will often never fire right again, even if you take them out and clean them. I still can't figure out why, its never been true for the cars I worked on, and I always feel silly typing this in (its about the only story I've got) but that's the truth of it. A local mechanic let me on to that or I would have trashed my bike long ago.

Not saying its your problem at all, sometimes it doesn't work that way at all, but if you're plugs are pretty carboned up, it could be. Good luck.

[Anonymous]

Thanks for all the advice. In the words of the philosopher Joe Dirt, I'll "just keep on keepin on."