82 R65 won't start

[Siouxzy]

I have been dealing with ignition problems on my LS for a while now- First, the bike was having loud back fires and periodically stalling- it finally left me stranded many miles from home. My mechanic said it was the Hall Sensor- we ordered an Omega replacement from Rick Jones back in MAY- it still is "NOT IN STOCK" so we put used hall sensor in there temporarily- which seemed to fix it for a few days- then it had more issues- so we replaced the coil. - i rode it home (about 45 miles) and was happy!! The next day, i went to start it and it cranked, did not ignite, and when I turned it off there was a loud back fire. :-/ I posted my info on the Airheads list and several folks said to adjust the valves- I adjusted the valves, and installed new spark plugs but it still won't start. I contacted my mechanic who said the only thing left to replace is the ignition module under the tank so I took the one from my running R100 and tried it on the LS but it still won't start. When I lay the plugs (in the wires) on the cylinder heads and turn the key they both spark- but the bike will not start. I am stumped and my mechanic is not responding to my emails or answering my calls. I am at a loss.  :'(Any ideas? thanks

[Bob_Roller]

Have you operated the starter with the plugs on the cylinders ??
What color spark do you get ??

[tunnelrider]

It does sound like a problem with the electrics in the ignition circuit.  But to go back a step, have you tried starting it without the air filter?  Also have you checked your choke cables are properly set and you're using the choke?  Spark plugs aren't getting fouled by turning it over?  How old are your spark plug leads?  I assume you have checked the fuel lines.  Are the idle mixture screws underneath the carbs set at least 1/2 a turn out from a light seating?
But since you've probably gone through these steps yes the quality of spark at the plugs will be a good indicator.

Sounds like a damn annoying problem you're going through, sorry to hear.  
I had a problem with dirt and water in the spark plug well of my dirt bike that prevented it from starting and had similar symptoms.  So that problem was the electrical pulse going to the spark plug shorting to the cylinder head.

P.S. When you check the spark with the spark plugs out make sure both are touching the cylinder fins firmly (or wherever you choose to ground them) as apparently the post '81 electronic spark system doesn't like being ungrounded when firing and will lead to problems if not done properly.  Don't let this put you off, just use some duct tape or similar to hold the spark plugs down nice and good....

[Tony Smith]

Ok, so you have replaced the Hall unit with a known good one, you have swapped out the coil and you have replaced the ignition amplifier with a known good one.


It might just be me, but I reckon you are barking up the wrong tree.

Let us pray from the book of airhead:- if you think it is electrical, it is probably fuel. If you think you have a fuel problem, it is probably electrical.


Seriously. You have spent so much time and money chasing an electrical problem and your fault remains, these are not complicated machines.

[thrang]

I don't think its the ignition, assuming you have checked the plugs and the HT leads and you said you have a spark. So I'd take a good look at the fuel system.
Starting with the obvious, your tank has not collected water bellow the fuel?
Then I'd make sure the little gauze filer in the petcock assembly is clean.
Next the carburettors.
Whip them off one at a time and give them a good clean out, making sure that the floats are free, and that there is no crap jamming the float needle. Check that the jets are clear with a blast of compressed air.
Make sure the chokes are not jammed and that you have good movement in the cables. Finally I'd have a look at the diaphragms although problems with them usually show on running motors rather than stating.  

(Rebuild kits are not expensive and its a fairly easy job with a good manual or helping hand. BTW if you do rebuild them, only do one at a time then you can reference the other one when reassembling)

Hope this helps.

[montmil]

While the plugs are out, dribble a little petrol down the sparkle plug holes. Replace the plugs and leads. See if she wakes up and runs for a few seconds. If the engine lights off, you have pretty solid confirmation that carb rebuilds are in your future.

Let us know what happens...

[tunnelrider]

One thing I didn't mention is that the bike's original grey coloured coil under the fuel tank is almost the only stock item on the bike electrics that usually fails. Most would've been replaced by now but it might be worth checking the colour of the coil (the big piece that the spark leads run from).  Mine is green and looks as if it was changed a long time ago, by a previous owner.

[montmil]

Ms SiouxzyQue posted her question on August 30. Lots of good responses but not a peep back from her.

Whazup wif dat?  [smiley=huh.gif]

[tunnelrider]

Indeed Monte, the fix may've been so basic it was not worth her remembering the question?  Looked quite plummoxed with all the smileys and not so smiley though...  We have another member!