Question about 1977 Honda Cb 400 F

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1977 CB400t Hawk will not idle

I have a 1977 400t Honda motorcycle it will not idle on 2 cylinders will only fire on 2 at 2500 revs, carbys have been sonic cleaned and bench set up. What could be the problem? Thanks

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Hi, Philip I can help you resolve this issue but there are 2 main reasons along with a bunch of variables that prohibit me from doing it on this platform:
1. I do not know the history of your bike.
2. Multi diagnostic issues, fuel, electrical, mechanical etc.
The best thing to do is to contact me at so we can address these multiple possibilities.
Good luck and have a wonderful day.

Posted on May 19, 2017

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Posted on Jan 02, 2017

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Ihave a1977 400t honda that wont run on 2 cyls at idle cuts in at 2500 revs carbys sonic cleaned plenty spark help. Thanks

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