I need a bit of general guidance/advice on my '83 650.

[Blok]

I got the Nighthawk for $250, runs good, has a few minor minor issues. I have a thread on the other forum if you want to see the bike :)

Now, my question is this: I have been working way too much lately and it's been too cold, etc etc so the bike has sat in the garage. The problem is that now it won't start. It turns over but just doesn't turn over quite enough to crank. I guess the battery is a little too weak to give it the full juice?

Also, when I stop trying to crank it, about a second later, there is a bit of a phuTT sound from the exhaust.....is this simply a bit of built up something or other escaping when the starting is stopped?

Sorry for the very vague descriptions but as I'm sure you can tell, I'm a bit new to motorcycles and working on them.

[detdrbuzzard]

you have to have a fully charged battery and your attempts to start it may have flooded the motor

[ExTex]

It sounds like you got a good price on the 650.  I really like my 1983 650 and hope you do too.
Glad to have another Nighthawk owner.

Yes, the battery is the 1st suspect.  Mine has an old battery and I have to charge it in 2 weeks if I let it sit.

Check the battery liquid level.  Fill it with distilled (only) water if needed.

Clean the battery posts and connectors.

Use a battery maintaintainer.  WalMart has them for $20.   
Do NOT change at more than 1.5 amp

A new set of sparkplugs are probably also a good buy.  Get NGK at OReilly's auto parts, they are the cheapest.

Add some Sea Foam to the gasoline.  It will clean deposits off the carburetors.  WalMart has the best price.

Enjoy a great bike.

Ride  safely,

[Blok]

Hey, thanks a million for the advice. I will definitely do those things you mentioned on my next day off.....if I ever get another day off :)

So, is the 'phuTT' sound anything to worry about?

[ExTex]

phuTT sound....I can think of 2 possibilities

1.   There is some unburned gasoline that sorta burns when it reaches the exhaust area.  I doubt this because
the exhaust area should not be hot enough to set off the gas.

2.  There is an exhaust valve that isn't opening because the hydraulic lifter has lost prime and the compressed gas & air escape when the pressure gets high enough to push them through the valve opening.

This happened to my bike once when I let it sit a long time.  The bike worked fine the next time I started it.

You can search the forum for more information on what to do if this is the problem.

Get the battery problem solved and then worry about the phuTT sound.

Ride  safely,

[Blok]

Again, thanks for the advice, I have tomorrow off so I am heading to Walmart bright and early :)

[Blok]

Ok, I'm completely embarrassed and will accept any (good natured) calls of NEWBIE but ummm, how do you remove the seat? I've googled it and tried everything I could find  but nothing works. What is the correct method of removing the seat on a 1983 NH 650?

[Zugzug]

LOL pull the side covers off. There is a bolt on each side. dont feel bad, your not the only one that had that problem.

[Blok]

Suuuuuure, that sounds easy enough. I'll be back in twenty or so minutes to ask another goofy question :)

[Zugzug]

The phutt is probably nothing. When the battery is weak or low it can have enough power to spin the motor but not enough left over to send spark to the plugs. If you decide to jump start it make sure the car/truck your jumping it from is not running. The bikes electrics cant handle the auto alt output.

[Blok]

Yup, that I knew :) At this rate, I might be able to ride in 3.5 years!

[JordanA]

Mine Phutts too.  I've noticed no ill effects.  It is usually after I've been riding the bike for a bit and then turn the key giving the electrics power again.  I feel like it is the starter just pushing out sir somehow.  Nothing serious in my opinion.

The two bolts for the seat are right at the base of the rear cowl (or fender if that makes more sense).  There is one per side, 10 or 12 point, forget which.  Slide the seat forward towards the tank a bit to remove it, because there is a clip that holds the rear of the seat in place beneath it. 

You can do it.  We believe in you.

[Blok]

Holy smokes! Three things:

1. I really need to have more time off :)

2. I really need to get better lighting in my garage.

3. Whoever designed the inner parts of the Nighthawk must be a LOT smaller than me. They got a battery in there? Really? Where the heck do the chargers go ?! :)

[Zugzug]

LOL, I usually put the connectors on the battery that the charger can plug into but I havent gotten around to it on the hawk yet. Since I been using AGM batteries I very seldom have the need. If you do need to jump it you can hook the ground down by the starter and the pos on the battery or the relay.

[JordanA]

I connect my charger/tender to the battery and the frame rail.  Positive to the battery (outside terminal) and the negative to the frame itself.  No problems.

[Blok]

Ok, I'm still here and the Nighthawk is now running but the brakes are a problem. Seems the left side of the brake system is frozen. Is a rebuild kit sufficient or do I need to replace everything? Price range?

We have moved since last time I posted but the guy next door loves Nighthawks and stopped me as soon as he could when he saw the bike in the carport. He is an Engineer so has been over hlpeing me get things right, time permitting. He has a Suzuki DR 200 so I imagine we might be riding some in the near future :)

[ExTex]

Ok, I'm still here and the Nighthawk is now running but the brakes are a problem. Seems the left side of the brake system is frozen. Is a rebuild kit sufficient or do I need to replace everything? Price range?

We have moved since last time I posted but the guy next door loves Nighthawks and stopped me as soon as he could when he saw the bike in the carport. He is an Engineer so has been over hlpeing me get things right, time permitting. He has a Suzuki DR 200 so I imagine we might be riding some in the near future :)

You really need to pull the calipers apart to see what is needed.  Most likely, all you will need are the rubber components and some elbow polishing.
Usually the rubber components are cheaper individually than in a kit.. I think.

I redid a stuck piston on my Sabre last fall and all it took was polishing the piston and new fluid.

Ride   Safely
 

[niteman]

I just redid the caliper on my450sc not too long ago. I agree with the above statement that you just need to pull them apart to see what needs done...very doubtful that you need all new parts. What I did was just order new rubber seals and bushings before I took it all apart, I figured that the bike was 23 years old and it wouldn't hurt to have new soft parts down there.

There is a lot of good info on here for dealing with a stuck piston too, just do a search. If you use air pressure to release the stuck bastard, don't turn the pressure up past 20psi, and practice patience. BTDT.

[Ghetto]

I feel like this is me last year 

Ya, I have an 83 650 and that thing will not start after the battery gets a little low.

[flyingbrick]

Frozen pistons can be really fun to remove. When I did my brakes I found that all 4 of mine were frozen. I tried air and stuff but none of that worked. I ended up going to an auto parts store and just kept grabbing brass fitting until I wound up with a tool that screwed in to the caliper on one side, and ended with a grease fitting on the other side. Pumped the calipers full of grease and the pistons came right out.

[niteman]

When one of my pistons was frozen, it took a couple of different attempts, over a couple of days, but here is what I did (and the next time I have to deal with that, it won't take as long).

The process was this:
-I soaked the stuck bastard down with PB blaster and let it sit.
-Using air pressure (too high at first-45psi) set at no more than 20psi, I placed a thin block of wood to fill the gap between the piston and caliper body, secured the free piston with a c clamp, and applied air pressure to the brake fluid inlet. It didn't budge.
-I soaked it in blaster overnight.
-i went back and tried again to no avail. I posted a pic on here and someone pointed out that the piston looked canted a bit.
-I used a c clamp to depress the stuck piston as far down as it would go and then applied air pressure. I repeated this process a couple of times as the piston would come out a little and then stop. After a few minutes it popped out and I was able to finish the rebuild.

The inside of the cylinder was funky. A good thorough cleaning was in order. After all was nice a shiny clean I installed the new o rings/seal that I ordered from hondaparts-direct.com, applied thin layer of brake fluid to pistons, and buttoned it all back up.

Worked like a charm ever since.

[Blok]

Thank you all for your advice, my neighbor and I will take it apart this weekend.

[Blok]

Ok, next topic for anyone still willing to read this and advise:

When the bike idles for about 5 minutes or more, there is a very strong gas smell. Does this mean a carb problem? I'm going to run some sea foam in the tank to see if that helps any...can't hurt but if anyone has some advice or experience with this, your insight is appreciated. And thanks for all of the advice I have received so far, it is very appreciated.

[niteman]

Could be a leaky float bowl gasket.

Could be getting too much fuel, like running too rich.

Start with the easy to check stuff and go from there.

I am just starting to delve into carbs and fuel systems myself, so someone else could chime in on this. Also check the oil to make sure there is no gas in it as that would point to other problems as well.

[Blok]

Ok, bike is running and running pretty well, thanks for all of your advice!

I think the problem with the gas was I had left the petcock in the on position. The front brake still needs some work but the bike stops fine. However, I'm not going any further than around my block until it is completely fixed.

As for riding a Nighthawk, 'Wow' is all I can say. I didn't get crazy or anything but that bike is nice! I'm rusty as heck but the bike smoothed out nicely in a short amount of time.