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81 xs400 wont start


mankie
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Last year the bike got dropped it was a soft laydown but it went down. Over the winter i put new valve stem seals in and reseated the whole thing, I honed the cyclinders and put new rings on and finally rebuilt the carbs. This was all done by a shop not me except the rings lol

I have new plugs wires oil, oil filter ect. This bike is pretty much rebuilt... I can get fuel in the carbs. I crank it over and it just wont jump it sounds like its about to but doesnt. after several attemps it will backfire on me and thats LOUD, this bike doesnt have points or a condenser in it I took the plugs out and grounded them to the side of the engine to see if they were sparking and they were but it was a faint spark but at least it was blue and it was the same on both sides.

Any Ideas???

I have a manual but it talks about points ect so if someone has an electrical diagram please let me know.

Chris

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Last year the bike got dropped it was a soft laydown but it went down. Over the winter i put new valve stem seals in and reseated the whole thing, I honed the cyclinders and put new rings on and finally rebuilt the carbs. This was all done by a shop not me except the rings lol

I have new plugs wires oil, oil filter ect. This bike is pretty much rebuilt... I can get fuel in the carbs. I crank it over and it just wont jump it sounds like its about to but doesnt. after several attemps it will backfire on me and thats LOUD, this bike doesnt have points or a condenser in it I took the plugs out and grounded them to the side of the engine to see if they were sparking and they were but it was a faint spark but at least it was blue and it was the same on both sides.

Any Ideas???

I have a manual but it talks about points ect so if someone has an electrical diagram please let me know.

Chris

I have some values you could check with an OHM meter...

spark plug cap 10kohms

pickup coil 700ohms +/- 20% @ 68'F

Coil primary resistance 3 ohms +/- 10%@ 68'F

secondary resistance 8.6kohms +/- 20% @ 68'f

If the sparks are weak, they def won't fire under compression conditions. make sure battery is fully charged.

drewpy

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I have some values you could check with an OHM meter...

spark plug cap 10kohms

pickup coil 700ohms +/- 20% @ 68'F

Coil primary resistance 3 ohms +/- 10%@ 68'F

secondary resistance 8.6kohms +/- 20% @ 68'f

If the sparks are weak, they def won't fire under compression conditions. make sure battery is fully charged.

drewpy

Perfect this is what im looking for i will give it a shot thanx.

Chris

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