Topic: Swapping a CB550 into my CB500...so close, and yet so far.... DONE!!

[Scott S]

 So, I picked up this '76 CB550 engine, carbs and a complete wiring harness from Craigslist. Only $125!
  It has 26K miles on it (which is more than the 14,000 on my CB500), but it looks well taken care of. Pulled the oil pain for inspection, gave it a good tune-up, rebuilt the carbs (just to be sure) and did a little detailing. My CB500 runs great, but it has some oil leaks around the head (probably the pucks), most likely because it sat in a shed for 28 years. I'm sure the gaskets and pucks are old, dry and hard. It also suffers from the common CB500 tranny issues, like the occasional false neutral, usually between 1st/2nd, and, rarely, a missed shift between 4th/5th. Great bike, though, and an early production model.
 Here's the 550 engine and it's new home.

[Scott S]

 Out with the old....


 ....and in with the new!

[Scott S]

 I thought I was going to have some wiring issues with the alternator. The plugs didn't match up.


 Then I remembered that I had a known good stator/rotor in my parts pile. Just swapped the innards over to the polished alternator cover and it was plug and play.

[Scott S]

 After this pic was taken, we got the header/exhaust on, swapped in a new rear sprocket (to match the 550 tranny ratios), and actually heard it run!
 I kicked it over 40-50 times but couldn't get the oil ight to go off. I tried it with the starter/kill switch on, and after maybe two coughs, she came to life! Oil light went out, no death rattles, no smoke, no leaks.....YAY!
 However, success was brief. I couldn't get the advance to retard enough. I was swapping over my Pamco from the 500, but using the advance mechanism on the 550. I pulled the 500 advance and it turns out that I had a loose spring on the 550 advance.
 That would have been an easy swap, but I'm afraid I may have damged something when making the swap. I no longer have spark on 2/3. It was running on all four before. What REALLY sucks is that I can't trouble shoot to see if it's power, the coils or the Pamco because my cheap, P.O.S. Harbor Freight multi-meter is just that (and now has a new home in the trash can) and my "good" multi-meter has a dead battery! Aaaaargh!!
 I'll get a battery tonight and hopefully do some trouble shooting tomorrow. I was thiiiiiiiis close to taking a test ride!

[Scott S]

 Oh, and I forgot to mention: We also wasted over two hours yesterday futzing with the clutch cable, basket, cover, etc.
 I was told that I needed a 550 cable because it was longer, so I had a new Honda cable on hand. However, since I'm running 400F bars, I thought I'd try the shorter CB500 cable.
 Well, it's not so much the cable length as it is the SHEATH. Swapped in the 550 cable and had the clutch adjusted in 5 minutes, but only after pulling the cover twice, disassembling the actuator twice, checking out everything we could think of and getting into a shouting match with my father.
 Save yourself the headache. You MUST use the 550 cable. 

[grcamna2]

That's a nice looking swap .

[dave500]

yeah the 500 and 550 cables have a different free length,some one else not long ago went through the same thing,,nice looking engine,i use the 550 engines,youll feel a little more pull all over and a slicker shift,that kicker might also foul on your side cover youll have to use the straight 500 one.

[bryanj]

Cable problem is strang 'cos here in UK in the High Level catalogue they list the same cable for the 500/550/750

[dave500]

ive done the swap twice and the cables wont work.

[Deltarider]

Cable problem is strang 'cos here in UK in the High Level catalogue they list the same cable for the 500/550/750

Probably because we were blessed with euro bars and not those dreadful sit-up-and-beg type bars.

[dave500]

500 cable is 22870-323-000 and 550 one is 22870-374-000 in my lists,with the two side by side youll see its the free length of the inner that fouls you up,i found the photo i used in the other thread,you need this much free cable with the handle bar end disconected,three inches.

[Scott S]

 Dave is right. It's the free length that differs. I was hoping to use the shorter (overall) CB500 cable with my 400F bars, but there was just too much cable exposed. It simply will not adjust out.

 Dave, that kicker is from a 550F and is used because I'm also running 400F footpegs/controls. Works just fine.

 Got a battery for my multi-meter last night. Plan on trouble shooting later today.

[Scott S]

 Success!!!
 I found a loose wire, probably something that I disturbed when swapping the advance unit. Runs great with a LOT more power than the 500, especially in the midrange.

 I may want to tweak the clutch and carbs. Carbs were bench synched, but I think I need to fine tune the IMS screws and maybe throw on the vacuum gauges, just for final tuning. Only other issue is that the neutral light stays on. I just need to adjust the switch against the cam. Worst part of that is removing the side cover again.
 Can't wait to put some miles on this one!

[dave500]

good one scott.

[Scott S]

 Lubed the clutch cable and it's MUCH better. Don't know why I neglected to do that before the installation... 

 Tweaked the IMS screws and got the bike running even better. Will probably still fine tune that and, eventually, vacuum synch the carbs.
 Runs SUPER strong with no leaks or other issues. Just need to pull the sprocket cover and adjust the neutral light switch now.
 
 Here are some crappy garage pics.

[pamcopete]

Scott,

Looks great! Even better, it runs great too. Guess you are in the market for some 550 side covers! 

[seanbarney41]

Scott,

Looks great! Even better, it runs great too. Guess you are in the market for some 550 side covers! 

nahh, let her sleep

[Scott S]

 Exactly...let everyone think it's "just" a 500.

[Scott S]

 Some fresh pics. Man, I'm really loving this bike now. I really, really enjoyed riding it before, but the 550 swap and the new Halcyon mirrors really make a HUGE difference.

[tango911]

Looks awesome!!   want to sell your xs650 ?   

[Scott S]

 Everything is for sale....for the right price. Indy is a little far away though, isn't it?

[Tews19]

Some fresh pics. Man, I'm really loving this bike now. I really, really enjoyed riding it before, but the 550 swap and the new Halcyon mirrors really make a HUGE difference.

Wow she looks great... Look like my 750's sibling... You have a video of the bike running? Do you feel any difference from the 500 engine?

[Scott S]

 There is a major difference between it and the 500. My 500 was a little leaky, probably from bad seals from sitting in a shed for 28 years, but it ran well. I did a compression test when I first got it and, while a little on the low side for a couple of pistons, it was within range and within 10% of each other. Never smoled, never used oil.
 The 550 (this one is stock as far as I know) has MUCH more power all over, but especially in the midrange. It also pulls a few less RPM's at 50-60 mph, using stock sprockets (yes, I swapped in a stock 550 rear sprocket).
 So far, I'm really impressed.

[Tews19]

Video or it never happened! Just playing

[Scott S]

 Maybe Monday, when I'm off work again. I rode a little today, but it's 40-something freaking degrees here!