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xs400E


victor400
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Hello, new to the forum but not new to motorcycles. I currently have a Seca 750 that is running well. I just bought a

1978 xs400E that has been off the road for at least 7 years. I got it started after a quick and dirty carb clean, unstuck the floats and slides. After it was running I noticed the right muffler(as I am sitting on the bike) was much hotter than the left.

Bike runs rough but I expected that. Any suggestions on where to go from here?

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Hello, new to the forum but not new to motorcycles. I currently have a Seca 750 that is running well. I just bought a

1978 xs400E that has been off the road for at least 7 years. I got it started after a quick and dirty carb clean, unstuck the floats and slides. After it was running I noticed the right muffler(as I am sitting on the bike) was much hotter than the left.

Bike runs rough but I expected that. Any suggestions on where to go from here?

pilot jet blocked ,also check twin contacts (if fitted) to check timing/gap

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pilot jet blocked ,also check twin contacts (if fitted) to check timing/gap

went over the carbs again, now there is no spark from the left plug there is spark to the right, how do I check the coil for viability? the wiring and connections do not appear corroded

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went over the carbs again, now there is no spark from the left plug there is spark to the right, how do I check the coil for viability? the wiring and connections do not appear corroded

coil primary resistance = 4 ohms (small wire and ht lead)

secondary resistance 9500 ohms (small wire to other small wire)

check ht cap not cracked and has continuity from lead

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coil primary resistance = 4 ohms (small wire and ht lead)

secondary resistance 9500 ohms (small wire to other small wire)

check ht cap not cracked and has continuity from lead

Swapped out the coils and can get spark from previously dead plug. So far I have traced it to a two prong connector for red and white wires(sorry I don't have a wiring diagram yet) it connects both red and white wires to a single red and wire in the harness. One side works with both coils the other doesn't. I am confused one connector(brass) that connects both wires but one side does not conduct current!!

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Swapped out the coils and can get spark from previously dead plug. So far I have traced it to a two prong connector for red and white wires(sorry I don't have a wiring diagram yet) it connects both red and white wires to a single red and wire in the harness. One side works with both coils the other doesn't. I am confused one connector(brass) that connects both wires but one side does not conduct current!!

redwhite is the + feed from ignition swtch and connects to both coils. Grey and orange go to the conacts via condensor.

the connector must be faulty or just needs some contact cleaner as they can get verdigri and prevent contact.

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Thanks for all the replies. Here is a list of things that were wrong with this bike.

1. Points were improperly set, left side was grounding itself.

2. Air filters old and falling apart.

3. Carbs seriously gunked up. Swapped them out with a set from an 81 400 that were amazingly clean even after sitting for years, cleaned up quickly.

4. Pilot jets on original carbs slightly mangled and unremovable. right side had air flow carb problem

New clean carbs, points set correctly(timing to follow no timing light yet, new breaker plate ordered) and it fires up.

Mostly this is a list to help others with similar problems, and thanks for the help

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