Topic: Registry of 650 Owners

[cb650]

Mine started at 15 a couple times last year even with sitting out all nite.  The ride after was very short.

[Pinhead]

I absolutely LOVE the '82 Nighthawk. If I could find one for sale for the right price I'd hop on it in a heartbeat.

[MikeB]

Hey all. Here's my 82 CB650 Nighhawk SC or "Luxury Custom" if you happened to live in Tokyo. The last SOHC4 made by Honda. 8k miles, nice shape but has a few issues: a nasty tank (old kreme), oil leak, and some pretty grating bad vibes at 5000k or so. Other than that she pulls nicely and has started up every day so far even in 12 degree NYC weather. No charging issues!

Nice looking bike jeepster
wish i could get my front end back together, bent forks  probably dumb ? but does anybody know if any year 650 forks will work on an 82 nighthawk, mine keep measuring out at (1.456") 37mm  from post i've read shouldn't they be 36mm looking at parts fichs for differant years none have the same part #s
or am i worring too much about a slight bend ??

[Frankenkit]

*shakes fist* that was my problem, I've never been able to find out really what forks are interchangeable with what.   I *think* all 650 (at least 80-82) are interchangeable with the difference of course of air-assisted vs. not.  the 79s were truly different animals, but may have the same fork, too. I dunno.

[Soos]

You got 37mm forks??

'79 forks are 35mm, '80 air assist, '80 non air assist, '81 air assist are all 35mm.
Beyond that I dunno.
Have noticed a slight height difference between the years, but cannot for the life of me remember which is shorter, and which was longer.

Then again it could have been the air assist just poking the tubes up higher... ?


Anyways... for 650 replacement forks....

DOHC ('79 at least) front ends use 35mm forks. 
For my '79 I used DOHC '79 750 forks, disks and bolts, and calipers.
Put the disks and bolts on the '79 cb650 rim, and the forks into the stock cb650 tripple tree.



I know that the '84 ninja forks I have are 37mm.
I also know a '84 ninja front tire will not fit(caliper to disk orientation) a '79 cb650 front end.


'79cb650 and std '80 use a narrower trippletree.

The customs have a wider spacing to their tripple tree, for the(stock) extra disk??





l8r

[MikeB]

You got 37mm forks??

'79 forks are 35mm, '80 air assist, '80 non air assist, '81 air assist are all 35mm.
Beyond that I dunno.
Have noticed a slight height difference between the years, but cannot for the life of me remember which is shorter, and which was longer.


l8r

Yea ,kept coming up with 1.456" (37mm i think unless my math is wrong) the triple tees are diff too the nighthawk
uses the 2 bars that fit into holes in the triple, think the rake is diff. too, along with the length, might be longer ?
hate to change out the triple tees and forks, my lowers are in good shape as are the calipers

Soos your 82 650, a custom ? are they 35mm also ?

Don't know anything about forks but
going to assume they should be fairly straight and not tweaked, hopfully can find someone who can straighten them without scratching them up, or maybe make sure the bends are parallel when i put em back together 
any suggestions would be most appreciated

Thanks Mike

[jeepster]

. Other than that she pulls nicely and has started up every day so far even in 12 degree NYC weather. No charging issues!

Starts at 12 degrees?  Wow!  My 82 CB650SC has a hard time at 32 degrees!  (But starts up, nonetheless)

Looks good.

Lee

Thanks. I should mention that I have to hold the throttle open at 2k for a few minutes to get her to idle...dies with just choke.

[Frankenkit]

sounds like idle jet (or pilot screw) issues.

[Pinhead]

. Other than that she pulls nicely and has started up every day so far even in 12 degree NYC weather. No charging issues!

Starts at 12 degrees?  Wow!  My 82 CB650SC has a hard time at 32 degrees!  (But starts up, nonetheless)

Looks good.

Lee

Thanks. I should mention that I have to hold the throttle open at 2k for a few minutes to get her to idle...dies with just choke.

That's how pretty much all 650s run. However, the choke mechanism should hold the engine at about 2000 rpm automatically; you probably need to adjust the choke mechanism so you don't have to hold the throttle yourself.

[leekellerking]

And, apparently, one has to readjust the choke and/or idle screw after installing new throttle cables.  (Or at least, one must if one tried to pull the carbs like the manual said).   

. Other than that she pulls nicely and has started up every day so far even in 12 degree NYC weather. No charging issues!

Starts at 12 degrees?  Wow!  My 82 CB650SC has a hard time at 32 degrees!  (But starts up, nonetheless)

Looks good.

Lee

Thanks. I should mention that I have to hold the throttle open at 2k for a few minutes to get her to idle...dies with just choke.

That's how pretty much all 650s run. However, the choke mechanism should hold the engine at about 2000 rpm automatically; you probably need to adjust the choke mechanism so you don't have to hold the throttle yourself.

[griff6-5-zero]

Will these CV carbs switch out with the Mechanical carbs on a 80 cb650..... Thanks

[Frankenkit]

Nope, the intake manifold size is different.

[griff6-5-zero]

Nope, the intake manifold size is different.

Thanks kit!

[Frankenkit]

no problem.

[Soos]

Will these CV carbs switch out with the Mechanical carbs on a 80 cb650..... Thanks

They will... but you gotta make 'em work to an extent.

3 things needed really.

1 the '81/82 cb650 CV carbs
2 '84 through '91(?92) carb isolators off of a kawasaki ninja.
3 the appropriate throtthe cables for the '81/'82 cb650 CV carbs.

You don't end up with picture perfect alignment.... but it works.
I have a post on fitting '84 kawa ninja(600cc) carbs on my '79cb650 bike.

The same instillation procedures apply for the CV cb650 carbs on a non CV cb650 head with those isolators.



Basically put the isolators on the head, get carbs in place, and tip the intake side down, and the motor side of the carbs up, so they rest in the isolators(not a perfect alignment)
then as rotating upwards, pull them on.
http://forums.sohc4.net/index.php?topic=40287.0
A little more difficult than stocker carbs with old carb isolators though.

If that gives you an idea.....



However you can run SOHC cb750 carbs(best ones to use IMO are the '71-76 carbs) on a '79/80 non CV cb650 head.
A drop in (if you cut off the push cable hanger)
Too boot you get to re-use the stocker '79/80 carb isolators.
The 750 carbs are 1mm bigger in diameter where they go into the carb isolators than the stocker non-CV cb650 carbs are, but it fits. with new carb isolators they fit really well.






I keep getting sets of the 600cc Kawa ninja carb isolators off fee bay now and again for about $10-$12 each set.
So far I have a '84 set, a 86 set and a '91 set.
There is a difference in pliability  only it seems through those years.
The '91's I have are noticably more pliable than the '86 and the ''84's I have.
do a search on "cb650 alternate carbs" or the like... there is quite a few posts.



l8r

[Soos]

Nope, the intake manifold size is different.

And so is the spacing of the carbs ports.


But if determined... where there is a will there is a way....




l8r

[griff6-5-zero]

Soos, you the man..Thanks for all the info. May just keep the mechanical, but the info is here if needed,..

[Frankenkit]

the major shortcoming in the mechanical slide carbs is that you can't whack open the throttle the way you can with CVs.  The benefit, however, is that you don't get pinholes in the diaphragms.

[Soos]

the major shortcoming in the mechanical slide carbs is that you can't whack open the throttle the way you can with CVs.  The benefit, however, is that you don't get pinholes in the diaphragms.

+1!!
Diagnosing a pinhole was a nightmare on my brother in laws yamaha 1100!



l8r

[Frankenkit]

I'm actually all excited to see what new, complete air cut-off diaphragms and throttle pump are going to do for my carbs, because mine were.... uh... kinda tore to shreds.  The throttle pump was ok, just kinda stiff... but I'm anxious to see the difference.

[sixty9byrd]

One more, a 1980 650-sumthin.  Missing a few pieces, just got it yesterday.  Hope to have it  going soon.  Sat for a while - will probably have to clean the tank - carbs are already off...

Up in the Great White North (London, ON) 

[Frankenkit]

beautiful!

[pit monkey]

One More, Fort Wayne, Indiana.  1981 CB650 , 13K miles with required head gasket leak.  But did rebuild the air forks last year and they were still at 14 lbs after sitting all winter.  1st ride this year, should have taken the winter gloves...

[MickeyX]

Kit and I just bought our 2nd 1980 CB650C yesterday and picked him up today. The 1st one (Kit's bike) is all done and runs/looks beautiful. The 2nd one starts getting torn apart this week. I know the carbs are gonna get a thorough cleaning and the tank is rust free as far as we can tell. It has an oil leak so new gaskets are in the plan. Rebuild forks, check the electrical, etc......... One thing at a time. I'm just glad we have some donated spare parts left from the 1st build and certainly a better knowledge base this time around.

Some beautiful bikes on here. So glad to see them all. 

[Hush]

Just don't tell me it has charging problems alright mickey!