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Issue starting after re-gasketing engine 77 k

tombonombona

The essence of man
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So a little while ago I was able to purchase my dads 77 K for $1. It had been sitting in the shed for 25 years, never moved and still had old gas in the carbs (yuck). So I brought it into the shop, kicked it to make sure it wasn't seized, which it wasn't, and began the tear down. So I got all the gaskets changed, and I am pretty certain I got the timing chain on the right teeth, the marks all lined up and such, put engine back in, hooked things up and went to turn it over. Turns over nice, no issues there, I made a temp gas tank out of a pop bottle for now and I know it is getting fuel, checked that it is getting spark also. I had the carb professionally cleaned and rebuilt, just don't have the filter box on at the moment... I've tried adjusting the timing plate from stop to stop and everywhere in between and it still won't fire... Couple times it chuffed a little but that was it. Any help would be greatly appreciated.

Tom.
 
When mine was running rich I never had to use the choke. After cleaning, adjustment, and changing the jets I have to use full choke and a little throttle to get it to start. When it chuffs are you adding any throttle? Guessing that without the filter box you have a very lean mixture that won't light well. I would put on the box and add a 1/2 turn out on your idle screws to start. I am sure there are others with good or better advice.
 
Just for the heck of it, verify that the wires from the points to the coils aren't crossed. Yellow goes to one coil, blue to the other. One coils goes to cylinders 1 and 4, the other to 2 and 3. I had one switched and it took me forever to figure it out because the guy I had gotten the bike from said the carbs needed work. Turned out that the wires were switched apparently when the points were changed. I took the easy route and switched the yellow and blue wires at the connections right behind the motor and under the air box.

If you haven't messed with the wiring this probably isn't the problem for you, but I'd check anyway since it's so easy. Heck, maybe you have the plug wires crossed.
 
Yup I would bet money on the ignition timing being 180 deg out. Its easy to get the camshaft in 180 off from the ignition timing.
 
Easiest thing to do is swap the wires, thats what I do first thing if it wont fire and timing seems way off.
 
I should have said if the crank is 180 out then your ignition would fire on the wrong cylinders(cam set to marks and crank accidently set to 2-3 tdc instead of 1-4 at tdc. If the cam is 180 out it wont matter to ignition system because it fires paired cylinders anyway. Sorry for the confusion its been a long day.... Anyway swap the wiring and it will probably fire. I think I have confused enough people myself included, time for bed lol
 
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Bit of an update. I put the airbox on just to try to eliminate any fuel mixture issues. I tried swapping the yellow and blue wires, went through the whole range of timing and got nothing, not even a chuff. Switched wires back and same thing, nothing. Checked the points gap, its on the small side at about 12 thou but that is still within spec.... I'm just about at my wits end with this bike.
 
Are the plugs wet? Have you double checked compression and double check valve clearance to make sure you dont have them tight? Tried extra fuel(spray carb clean or a very small amount of starting fluid)? If every thing checks out there double check your cam timing.
 
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