Is the firing order on a suzuki gsx600 the same as a gsx400

Question edited to include maker.
Question moved to sub category.

It is a well known issue.

https://www.google.com/search?q=04+Suzuki+Katana+600+backfires

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on the left ,i thought the firing was 1342

1,3,2,4

check and adjust the firing order of the HT leads.

check fuel is good and not older than 6mths if bikebeen stood long period ? carbs may need cleaning !

timing belt jumped timing..

sounds like the firing order is wrong. it should state the correct order in the manual

I would pull the plugs and let the gas into the cylinders to dry out , you may have a hydrolock engine after putting so much gas into it , recheck the firing order to be sure is OK ususlly when you see a carb backfiring and smoking the firing order is not right

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