Need help 84 DOHC 650 feels likes its running on 2 cylinders

If it's broken or just needs tweaked

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KC650AZ
Posts: 1
Joined: Mon Aug 03, 2015 9:59 pm

Need help 84 DOHC 650 feels likes its running on 2 cylinders

Postby KC650AZ » Mon Aug 03, 2015 10:14 pm

I have a 1984 Honda CB650 Nighthawk.


It has:
1. Pod filters,

2. 4-1 kerker exhaust

3 79k needles

4. 122 main jets with 2 shims

5. 35 slows

6. Good compression 135 - 140

7. New/used CDI box, wires and coils.

8. coils tested fine at 3.0 ohms

9. New battery

I just got the bike running but it's weak and feels likes its running on 2 cylinders

It burns a LOT of gas...It spits gas out of carbs and backfires, very hard to first start.

It has new plugs and once running I noticed that cylinders 4 and 3 are very hot but the plugs are normal ash color.

Cylinders 1 and 2 are much cooler and plugs look new and white.

For instance I checked header temps for 4 and 3 and they are each 400 degrees hotter than cylinders 1 and 2.

I am getting spark when tested on cylinder 1

I cleaned the carbs twice

What is wrong with this bike I can't figure out why its running like garbage. Which cylinders are actual working correct? The cold ones or the hot ones?
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