Topic: A few 550 into a 500 Q's...

[Scott S]

 I picked up a complete '76 550 engine last weekend. It has the 087A carbs and a spare wiring harness.
 Supposedly, it came from a running bike.

 I plan to clean the carbs and detail/tune up the engine and drop it into my '71 CB500. Pretty straightforward, right?

 A few questions, though:

1) The 550 engine was missing all the advance stuff; points plate, retaining bolt, mechanism, etc. I found all the parts and I plan on running a Pamco anyway, but the spare advance I have is from a CB500. It has "323" on it and "AD125-02".
  Any problem with running that in a 550 engine?

2) I did a search on the 087A carbs and see a few people having issues with them. I know that externally they're the same as my 627B carbs and all the changes were interanl: needle profile, etc. I'm guessing that Honda was going towards leaner running as part of the emissions process.
  I have a rack of 627B carbs that I could use to swap out jets, needles, etc. Any benefit to that?

[bryanj]

All the advance/points stuff is the same,
Main difference in carbs is jet sizes--its the later 77/78 carbs that are a real sod
You will also need the RH rear engine mount plate as it has the clutch cable stop on it.

Apart from that its good to go

[Scott S]

You will also need the RH rear engine mount plate as it has the clutch cable stop on it.

Apart from that its good to go

 Glad you told me that......back to the junkyard....

[Greggo]

Check this thread too...


http://forums.sohc4.net/index.php?topic=83545.0

[Scott S]

 This is what I needed, right?



 I guess that means I'll need the later clutch cable, too? My CB500 has the early style clutch cable that goes into the LH sprocket cover.

 Greggo, off to read that thread right now!

[Scott S]

 Oh yeah...I searched for quite a while the night I brough the engine home, but where can I find a serial # look-up?
 I'm 99% sure it's a '76, but where on this site is a cross reference?

[Scott S]

 And from another thread: "the 500 has a 34 rear sprocket,the 550 has 37,itll have a tall gearing if you dont change to a 37,the different transmissions have different gearing internaly".

 I JUST bought a new 100 link chain for my CB500. Haven't even taken it out of the box yet. I'm guessing it will be too short for the 37 tooth 550 sprocket?

[bollingball]

Scot there is another list I was looking for but can not find it. Maybe this will help.

http://www.sohc4.net/?page_id=2765

[Scott S]

 Yep, it's a '76 K model.

  And it appears that the 17/34 and 17/37 sprocket combos both use a 530/100 chain, which is good since I have a brand new one on the work bench.

[bryanj]

According to all the aftermarket suppliers the 500 and 550 clutch cable are the same.

That is the correct bracket

Also DO NOT PAINT the bracket where the big engine bolt goes through as this is where the battery ground cable goes and it need to make good contact with the bracket and the bracket good contact with the engine case