I just bought a Nighthawk 450 as well. My ignition switch was bad, but I managed to fix it 100%, as good as new. Don't forget that if you replace the switch, you'll have different keys for gas and for starting the engine.
This video helped me through the repair:

 

Likely you can take care of the front brake problems with a thorough cleaning of the master cylinder and caliper as well as the replacement of the seals. There's a tiny return hole in the master cylinder that commonly causes problems, been discussed here many times. If you're not concerned about a showroom restoration there are aftermarket master cylinders reasonably priced which can get you on the road.

Do a search on tank liners, there are better options.

 

Moved to "Member Intro's"
Check the SOHC section for information on this model

 

Redkote is a good tank liner/sealer but requires the fuel tank to be Absolutely as dry as it can be..like 'desert dry' so the Redkote will stick/bond correctly to the steel inside your tank;a good bit of prep work should be done to clean out as much old gummed up gas inside it as possible also.

 

The ignition switch in mine has a pigtail with a 6 pin connector but the base is missing from the switch.
Could i use this? Emgo Ignition Switch Repair Kit 40-15810
Will other model Nighthawks ignition switch work?

I read reviews on the Red-Kote Liner and i am going to give it a try. Thanks.

 

[h=3]Assemblies where 35100-443-921 is used[/h]

• 1982 CB450SC A - HANDLEBAR / TOP BRIDGE / KEY SET
• 1983 CB450SC A - HANDLEBAR / TOP BRIDGE / KEY SET
• 1985 CB450SC A - HANDLEBAR / TOP BRIDGE / KEY SET
• 1985 CB450SC AC - HANDLEBAR / TOP BRIDGE / KEY SET

 

The Nighthawks use a smaller connector than the earlier CB/CM 450's

 

Not sure what you are saying?
Will this work? Emgo Ignition Switch Repair Kit 40-15810
It should plug right up to the female end of the harness?

 

BamaRambler, I don't see your model listed in the 'this item fits the following applications' list.

 

dtsmjr8dan, I know its not in the list but looking at the part make me think it might work.
Here is my bad Ignition switch/wiring.

 

It looks totally different to me, but if you want to try.........that's all up to you.

 

The electrical part of the switch has two parts. Mine is missing the bottom portion of the switch.
The bottom portion is what rolls across the ridges inside the housing that with the turn of the key that aligns with the contacts of the switch.
Someone had told me that several other Nighthawks have same ignition wiring and some of those in the list for this part.
That is why i think the Emgo Ignition Switch Repair Kit 40-15810 might work.

 

The Emgo unit is a totally different switch than yours.
The switch you picture looks to be the large connector type, does it match the harness? The CB450SC's I've encountered have a a smaller connector with smaller spade connectors but I also haven't come across a '82 model either. Maybe the change took place in '83.
David Silver Spares sells a complete ignition switch for the early large connector that may work David Silver Spares USA - 35100-413-007P but it's not the same part number as yours

 

I have emailed David Silver Spares and per their reply email they cannot confirm this will fit a CB450 Nighthawk. This part is made to fit a CB250N 79/80 Super Dream.