HondaCB650

That makes a lot of sense. I will read over the McGrugor carb clean manuel again and recall my procedure. I understand the marker on the choke rod and that is a good idea - I will watch that a little more closely.

Thanks or the tips and I will see what I come up with next week when I can get back to it.

Glad to help out with the experience i gained during the rebuild of my carb set. (VB44C off of a 1982 CB650Sc Honda Nighthawk) Ours are very similar....

The best advice i can give is to have patience, the ability to walk away from it all and give it another think is an absoulute must, as most parts, including that nasty formentioned spring are no longer obtainable if you damage/ruin it!

There are a lot of persons here (advice from Volker P is golden!) that will get you through, as they did for me. hang in there, we'll get it figured out.

I really do believe that you have a little more cleaning to to with respect to jets and internal passages...here is why:

I dont know if this is actual fact, but when my carbs were somewhat clogged, the bike would start, with difficulty then it took choke to keep er going...When i revved the bike it revved up , but stumbled around back at normal idle. when i began the dissassembly and cleaning process, i noted that the low idle jets (on my carbs they are removable, on your they may not be?) were clogged, i could not even see down the middle of the jet. Granted this is a somewhat of a microsized hole, but it's there for a reason. I ended up using acetone and a heated ultrasonic bath to get them cleaned out, and the ultrasonic/acetone combination really did the trick, for the other jets as well!

I cleaned my carburetors as outlined in the McGregor manual, (link provided by Volker) step by step. all was good! the only area i had difficulty was the choke spring and alignment of the choke plates to their respectiverods and bodies... this took a few times to get it right & is why i took the time to explain this in detail., remembering how it affected my bike......

Once i got it all set and back on the bike, she starts quickly and easily, runs strong. You'll get there, am sure of it!

I would also highly reccomend that while you are in there, get the new o-rings for your fuel and accel pump rails as well as the ones for the accel pump assembly. The folks here should know the sizes for? In fact, i believe that the McGregors manual gives the sizes for these? have a second look... be sure to get buna-n or viton for best resistance to fuel.

Lastly, have you checked the intake boots for leaks? i also replaced their o-rings when i was doing the rebuild. mine were hard as a rock, compression set due to age and heat cycling. was easy to do whilst it was apart for cleaning.

Hang in there...enjoy your holiday weekend!

nashbuilder wrote:No i took the automatic petcock off and put a screw in the #2 vacuum port to cut it off.

So you have fuel directly in the carbs. Always good to know.

nashbuilder wrote:The idle issue I am not to worried about right now. I cant even get the bike to start now unless I spray gas through the airbox.

Nevertheless this migth be related. If your idle is too high, your flaps are open too much. This will reduce vaccum over idle passages and consequenly less fuel and more air. Additional fuel or whatever sprayed inside could help at such problems.
This may answer some of your questions I guess.

nashbuilder wrote: It idles fine when I start it up and just let it idle, but when I give is throttle it dies once the throttle is released.

All this sounds like some strange throttle behaviour. Loose cam, flaps, lever or so. Maybe sticky pistons. Or strange synchronisation status.

When you refer to flaps are you meaning the choke or throttle flaps ( plates, petals)?

When you refer to pistons - engine piston or carb piston/slides?
strange sync - engine sync/ timing or carb sync?
and loose cam - cam chain or the cam shaft?

I am sorry I just want to make sure I am confident the advise that I am being given. I really appreciate the 2 of you helping me out and I hope that I am able to get this straightened out.

Sorry, this was all about carbs:

So the throttle flaps on their (throttle) cam,
possibly a loose lever at this throttle cam,
the maybe sticky vacuum pistons of the CV carbs,
and carb synchronization.

The pistons move up and fall down no problem when I lift them with my finger (on the bench)
The Sync was good and we used a carb sync gauge.
The lever might an issue but on the bench seem to work everything just fine.
The flaps might be not be perfect. That was the one I was having the most problems with on the carb bench but got it working nicely before I put them on. I wonder if when installing the carbs something adjusted and maybe they are sticking closed?

I removed my pressed in slow/idle jets this weekend. I used a modified method based on:

http://www.cbxclub.com/forum/viewtopic.php?t=5507

Rather than the 4-40 tap and threaded rod mentioned in the above link, I used a 2-56 tap to tap about 3-4 threads into the top of the slow/idle jet. No drilling was needed as the hole itself was just about perfect for this thread size. Of course a 2-56 threaded rod with nut is needed as well. i bent an "L" at the top of the rod to make it easy to hold still while I "tightened" the 2-56 nut. The other nut you see in the picture is just acting as a washer. 2-3 turns of the 2-56 nut and the jet popped right out. No mess or fuss.

A few moe pics.....

very cool. Was along the lines of what i was thinking if I ever needed to do it. You going to retap for 82 jets?



Actually I would have cut it out then repainted every thing flat black.

Wow that was a great idea. I have purchased some 82 vb44C carbs that fit and have the screw in slow jets, but I might have to try this on my old ones to have a back up.

Thanks for the great description!
Something for the "internal links" collection.

cb650 wrote:very cool. Was along the lines of what i was thinking if I ever needed to do it. You going to retap for 82 jets?

Nope. Just going to clean the jets/ports and press them back in. Since they are already threaded, getting them back out (if needed) should be a snap.

So after running the bike around 150 - 200 miles I am still getting carb 3&4 running rich and 1&2 are good/lean. I had a buddy behind me and said that he could see a little black smoke from the tail pipes of 3&4. The carbs have all the same jets in them so where do I start with fixing this? I would really like 1-4 to be running the same.

Did you check out plugs, too?

If you have some oil consumption, this migth be valve stem seals. Or rings/cylinders.

Compression is more or less equal on all four? If this should be the origin of a difference like that I guess you should be able to feel the difference in compression when turning the engine by hand at the crankshaft with a 24mm socket.