Help?

#1
Hi everyone, I have a '74 (i think) Honda Z50, the spark plug has spark and gas is getting to the engine but I can't get it to fire.

Any suggestions to how I can get it running?
 

minidragbike

Supporting Speed Nut!
#4
It is most likely something to do with the ignition system. Mainly the coil, but I don't know anything about those motors.

If you had spark, then it would be the timing, but that's not the problem.

If there is a kill switch wire, check it. And make sure your flywheel is clean around the magnet area.
 
#5
You might need to clean the points. If it has set for a while, thats most likely it. They're under the flywheel. My brother got one this summer and we had the same problem. It had spark, but it wasn't enough. After I cleaned the points, it fired up on the second kick. You might want to try kicking it a few times with the throttle wide open first. It could also be flooding.
 
#7
i just picked one up and i have a suzuki trailhopper what i would do is to clean the carb and change the plug then try you might need to buy a carb rebuild kit when you have done that if it still doesn't fire check your timing
 
#8
i've already cleaned the carb and got a new plug, im gonna clean the points latert today so if that doesnt work i'll check the timing.
 
#10
The only timing you have on the ignition is the flywheel key. If the bike ran when it was parked, it should be fine. The timing chain times the cam,and if it's out, you won't have compression.:thumbsup:
 
#12
You need a flywheel puller,but if you're careful you can take it off without one. You can get them off sometimes with a small gear puller, hooking it in the slots on the flywheel. Or a not reccomended way is to have someone pulling on the flywheel an use a punch in the countersunk hole on the crank, and give it a few taps. You cant hit it too hard or you'll damage the bearings. More like snappy little taps. a liitle penetrating oil beforehand helps too.
 
#13
Sometimes you can get a little emory board like the women do their nails with,and put it through the slot in the flywheel and get it in the points enough to sand them.
 
#14
another easy way to get a flywheel off (it works better on cast iron flywheels) is to buy some penetrating oil or WD-40 and spray it all around the flywheel where the crank goes into it and let it sit (in the shade, not in the sun because the sun will just evaporate the oil) for as long as you have the patience, and then start tapping lightly on the back of the flywheel outward all the way around the flywheel. you can tell if the flywhel is loosening up, because if you look where the flywheel is wet from the oil and if the oil is getting rust in it and turning brown, thewn that means its eating away at the rust, and before you know it you'll get the flywheel off.
Damn, thats a long explanation.
 
#16
Maybe some dust in the pointsfrom sanding. If you can pull the flywheel and clean the magnets and the curved ends of the wound copper coils that would help too. There may only be one coil. If there's two,the coil with the finest wire windings hooks to your points, condenser and coil.The other one is for lighting and charging. Try a small screwdriver and a clean cloth and clean the points. Turn the crank with the flywheel on and make sure the points are opening and closing.You'll be able to see them opening when one or the other of the slots comes around. There should be a T stamped on the flywheel and a little pointed casting on the case above the flywheel. The points should be opening just as the T is lining up with the mark.
 
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#18
Maybe they slipped.They only open about .010. It's hard to see without good light. Line the T on the flywheel up with the mark on the case above it. Loosen the screw that holds the points,just a little. On the left side of the points there is a slot and on the plate is a slot that lines up with it. Use a screw driver that will fit in both slots at once and pivot the points til you can barely see a gap. Then watch them as you barely move the flywheel counterclockwise. You should see them open a little more.If you do, tighten the screw and try it.
 
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#19
The points manufactured today dont have nearly enough meat on the contacts to do and sanding of filing on. you can clean them a bit with a very clean business card rubbed through the contacts till it comes out clean. a little electrical contact cleaner helps also.filing the points was a trick from days gone by when the contacts were thick enought to file flat and clean and still have enough meat for a good electrical contact. hope this helps...jonnybiker..p.s if you sanded or filed them there most likely shot and need to be replaced before they will work again.
 
#20
If the Honda has the original points, there is plenty of metal there to sand. if there wasn't, I would have to replace the points in everything I own. A '74 Z50 would most likely have been manufactured in 1973. Usually the foot of the points that rides on the little cam will wear out before the contacts. I've only done this a few hundred times though. I have 2 ATC70s with sanded points, a ct70 with sanded points a Z50, suzuki TS125, Several Tecumsehs, Briggs,and Kohlers all with sanded points, and all run well:thumbsup: By sanding, I don't mean actually removing metal, just oxidation and minor surface corrosion.
 
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