TOPIC:

Was out riding my 81 305 csr last weekend when the engine died on me at a stoplight. After that it wouldn't start. Let it sit for about 10 min. and it started back up but ran really rough. So I cleaned the carbs, checked the timing and advancer, compression(125 on each cyl) and valve clearance(which was good), but it still runs poorly. The left cylinder spark plug is a tan color, but the right cylinder is black and wet. The right cylinder also back fires alot with flames popping out of the exhaust sometimes(it has shorty mufflers on it).
Sorry this is so long. Any ideas on what to do next?
Thanx!



Post edited by: vikfelix, at: 2006/07/27 16:05

Post edited by: vikfelix, at: 2006/07/27 19:34

Think I'd start with new plugs. Disconnect plug wires from coils and plug caps, if possible, trim wires slightly at both ends and reattach. Clean all plug related electrical connections before reassembly. tart, ride then report back.

BARNEYHYPHEN wrote:

Think I'd start with new plugs. Disconnect plug wires from coils and plug caps, if possible, trim wires slightly at both ends and reattach. Clean all plug related electrical connections before reassembly. tart, ride then report back.

I agree. If symptom recurs, try reversing the spark wires to see if the problem goes with the wire. Then you know it's the coil or spark-related on the one side.
If not, well then we go down a different road...

Ok, put in new plugs, same thing, switched the coils, same thing(this rules out the wires and boots cuz I switched them with it to). Switched the condensors, same thing. While testing I noticed it backfires thru the carb and it is now blowing white smoke out the exhaust excessivly at times when running. After I stop it, it smokes out the carb and exhaust! This is all only on the right cylinder, the left seems to run fine. Think I roasted the engine?? Any more help would be appriciated.

Thanx alot guys!!

Sounds like you might have a busted ring or bad head gasket. It should be too hard to fix.

donthekawguy wrote:

...It should be too hard to fix.

Somehow, I think that's a typo...

the cylinder has loaded up with unburned gook.
sounds carb related
re set the float on the right side and let it all burn off.

All right, latest update. Checked float levels and adjusted, let it run awile and now she idles like a dream. Checked the plugs and they now look good. Put it all back together and she started right up and idles great. Then I took her for ride and once I get going it starts to sputter and backfire and wont get up over 20mph(no smoke though). Got home and the bike still idles great. I checked the carb sync and they still are all good. One question though, I'm using an old set of automotive vacuum gauges and homemade adapters to sync the carbs, they do flutter a bit but I think I can get them pretty close. Would out of sync carbs cause this many problems? Thanx alot guys!
jk

vikfelix wrote:

...Would out of sync carbs cause this many problems? Thanx alot guys!
jk

I don't think so, not if it idles that well.
The thing about 20mph... is that about 3500rpm? Is this where you are off the pilot jets and on to the main jets? Sounds like you got some gunk in there. You might have got some of it out in your last adjustment. Do you use filters on your fuel lines?

Allright, took the carbs apart and dipped them this time(vs just spraying em). Set em up, went for a ride. Idles good, Runs good at high speed, but hesitates in between. Is there a way to adjust this out? I'm not real good with Keihin carbs, I've only worked on Mukuni's in the past. Thanx for any help!


jk