Topic: My Nighthawk 550

[Laminar]

My '83 Nighthawk 550. It's finally at a point where I feel comfortable sharing it, so here goes:





Over the past couple of months, I've completed the following:
- Oil/filter (10w40 GTX)
- Battery
- Stator
- Wiring harness
- Starter solenoid
- Starter
- Regulator/rectifier
- Front brake pads
- Fork rebuild
- Brake fluid flush
- Replace Horn
- Oil/filter (5w40 Rotella T)
- Rear end oil change
- Clutch fluid flush
- Oil/filter (15w40 Rotella T)
- SV650 handlebars
- New tires

I've put over 2000 miles on it since getting it, and it's treated me pretty well. The tank is in pretty rough shape with a lot of dents and scratches, so I wouldn't mind a repaint. Also the cam chain is rattling pretty good, and the valve cover weeps a little oil, so in the next month I'll be pulling that apart and installing a new gasket.

Yeah?

[Alan F.]

Yeah, I'm a fan of that bike. Shaft drive, 80hp, six gears, and no adjustments to ever make?  

My thought is to cafe it tastefully, like these viragos:

http://forums.sohc4.net/index.php?topic=52285.0

I wonder how tough a monoshock conversion will be on this frame, no oil tank, easy to relocate the electrics and battery...I wonder what the neck rake is?

1983 was a great year for Honda in the USA, many great bikes came here in 83 that we've never seen before or since.

It's on my short list of bikes to own.

[Alan F.]

OK, it's a 29* rake and ground clearance is listed at 6.3", sounds like shorter forks will do the trick to me, maybe even just slip the stockers up thru the trees a few inches and run clip-ons....instant risers.

My CB750K3 has 27* and my 93 CB750 has 29*

http://www.hondanighthawks.net/550.htm

Doh, ground clearance is 6.3", and front suspension travel is 6.3".............that's strange.

[Laminar]

Yeah, I'm a fan of that bike. Shaft drive, 80hp, six gears, and no adjustments to ever make?

Yep - I love the hydraulic valves and electronic ignition, too. Maintenance is a piece of cake, no tedious stuff, just changing fluids - oil, brake, clutch, and rear end.

[Alan F.]

Oh, hydraulic clutch too? I didn't see that in any of the specs pages.  I hear they're darn fast too.  I always thought it'd make a great hardtail chopper motor too.

[Laminar]

Yep. My one complaint is the range - with my typically spirited driving in town and on the interstate, I typically see 40-43mpg, which means I'm hitting the reserve by 100-110 miles, and since this is my only vehicle, I feel like I'm filling up about every other day.

[Alan F.]

Yeah that's not a big tank is it?  3.2 gallons I see... I wonder if other tanks will fit on there, maybe a 650 nighthawk tank? Nope those look like they're 3.6 gallons...

The tank on my 93 750 nighthawk is 4.7 gallons, and it looks like it'd fit a 650....maybe that'd do the trick if you can find one.

Maybe a jetting change will change your mileage? how do your plugs look? I bumped my 93 750 NH up two sizes on the small and large jets, I run a 4:1 pipe and still get 50-55mpg. Got them from www.chaparralmotorsports.com  good prices.  And maybe a pound or two more in your tires will help too.
-A

[Laminar]

Bumping my jet sizes up would make everything run richer, which would reduce my milage. I just got brand new tires installed and I haven't had a chance to run through a tank yet, we'll see if they made any difference.

[Alan F.]

Richer yes, but at lower throttle i would run more efficiently, no?
The plugs will tell for sure if it's rich enough as is.

[Pinhead]

Yeah, I'm a fan of that bike. Shaft drive, 80hp, six gears, and no adjustments to ever make? 

My thought is to cafe it tastefully, like these viragos:

http://forums.sohc4.net/index.php?topic=52285.0

I wonder how tough a monoshock conversion will be on this frame, no oil tank, easy to relocate the electrics and battery...I wonder what the neck rake is?

1983 was a great year for Honda in the USA, many great bikes came here in 83 that we've never seen before or since.

It's on my short list of bikes to own.

The DOHC 550 is 80 hp?  What's the DOHC 650 put out? I've always liked the looks and styling of the early '80s Nighthawks. The '82 SOHC 650 Nighthawk looks great but it ain't got no 80 hp!

[Alan F.]

This page claims 75hp @ 9500  http://www.cyclechaos.com/wiki/Honda_CB550SC

This page has specs for both the 82 CB650 (64hp) and the 83 (75hp) http://www.motorcyclespecs.co.za/model/Honda/honda_cb550sc_nighthawk%2082.htm

Lots of other pages I clicked on rated the 83 550 dohc as 64hp and the 83-85 650 as 72hp, these aren't all likely to be US specs though.

I always understood the 83 550 nighthawk to be a direct relative of the cbx550 that was available to the rest of the world but most americans have never heard of, I guess it was a pretty cool bike.

[guamster]

Does anyone know what the speedo ratio is on these bikes? 

Thanks in advance for any feedback.