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Discussion Starter · #1 ·
So the engine in my Nighthawk has been burning oil and seen better a days. a full rebuild is in its future. In the meantime however I have a spare engine I got for $200 from a 1986 nighthawk that I am going to install so I can keep this bird on the road as it's my daily driver. I found a $500 bike on craigslist and offered the guy $200 for the motor and told him I'd come and pull it. Story was that his friend had bought two nighthawks at an auction and made one run. The seller claimed that they had this engine running a couple weeks before I came to buy it (yeah, ok). When I went to pull the engine I turned it over by hand and it had some compression, pulled the valve cover, looked pretty clean, but I could smell varnish in the carbs, but saw brand new plugs in it.

Long story short I got the engine, carbs and gauges for $204, brought it to my friends house, put an oz of oil in each cylinder and turned it over a couple times.

Fast forward to now and I'm getting ready for the transplant. I'm working on a checklist before I try to fire it up and I'm hoping for some tips from you guys.

Here's what I've got so far:
adjust valves
adjust balance chain tentioner
manually adjust cam chain tension
fresh oil and filter (I plan to change it again after 500 miles)
new carb boots and o rings
new exhaust gaskets
new valve cover gasket

The bike is currently running fine, beside smoking like a Kawi triple, so I won't have to worry about fuel or ignition woes. Is there anything I am overlooking or something you guys would add before trying to fire up this engine?

Thanks for the replies.
 

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Discussion Starter · #2 ·
Also does it matter what order I do the valve and cam chain adjustment? rotating the motor for the valve adjustment would tighten the chain on the front of the engine right?
 

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Also does it matter what order I do the valve and cam chain adjustment? rotating the motor for the valve adjustment would tighten the chain on the front of the engine right?
I believe that the correct order is:
1. Cam Chain Tension
2. Valves
3. Timing
 

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No timing adjustment, CDI ignition.

Didn't see it but sounds like you're using the carbs from your current engine. If not, given the varnish smell, I would go through the carbs before installing.

If it starts/runs OK I'd go for a ride. Some city, some highway, bring it home and check the compression.

Personally, I would change the oil at not more than 5 hours run time or more like 200 miles.
 

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Discussion Starter · #6 ·
Yes, I am using the carbs from my current engine. That's a good call on a compression check, I hadn't thought of that. I'll get the oil changed out at the 200 mile mark as well. Looks like I might be able get this buttoned up next weekend, weather permitting. I'll report back and let ya'll know how it goes.
 

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Would it be advisable to approach it this way?

(1) first re-torque the head gasket.... This step specifically, why or why not?

(2) set cam chain tension

(3) adjust valve clearances
 
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