Topic: 1978 CB550K Stripped

[ampsrampstramps]

Got my first bike, a '73 CB450, a month ago and got my second, '78 CB550K, 2 weeks later. The 450 is mint so I couldn't cut it up. What follows is my progress on the 550. I have learned loads from this forum and you guys have been a huge help. Thank you.
For the 550 I want to trim all the fat. Get rid of everything I feel is unnecessary. Parts are being bead blasted and waxed to a matte finish. Frame is cut up and slimmed down. Electronics simplified. I've purchased some new things for the bike but I am going to try and modify the stock parts or build new ones myself. What follows is my progress of all modifications and issues related to mechanical, electrical and metal.

Vitals Before / After
Model: 1978 CB550K
Miles: 8,000+
Carbs: Keihin PD46C
Main Jet: Was 90 / Now 105 (may change)
Pilot Jet: 42 (stock)
Needle: 2nd from top (stock) / Now 2nd from bottom
Float: 14.5mm (can't find a definitive answer on this. Others say 12.5mm)
Exhaust was: Stock 4-4 / Now: Mac 4-1 with slight mod
Air Intake was: Stock air box / Now: K&N Cones (the 35mm do fit)
Battery: Ballistic 8 cell EVO2 LiFe
Electric: New regulator and rectifier from Oregon Motorcycle Parts
Bars: Renthal 7/8" Road Low
Dyna S ignition and 5ohm coils

I will update the list as I go.

The bike as I got it

[ampsrampstramps]

FRAME
First thing I did was cut the tail of the frame off.

Got the curve with some 1/4 inch bar


Had some 1 inch tube and I heard you can fill it with sand, weld caps on and bend it and it wont crush the tube.


The tube filled with sand and capped in the bender.



The sand method didn't work. Crushed the tube but the curve is right. Pick this up again later.

[ampsrampstramps]

Bead Blasting

[ampsrampstramps]

BATTERY

Ballistic 8cell
I mounted the battery under the swing arm off of 2 existing bolts on the engine. The bolts are off center but if you flip the rear brake screw in the last picture you can get a bit more room and get it centered.






The cables slide right up behind the swing arm.




All of the tabs for the electrical panel were chopped, the stand was chopped and the left side exhaust/peg support.


I don't know why the pics are being flipped horizontal when they were shot vertical. But you can see the bolt that can be flipped to open up over a 1/4 inch.

[ampsrampstramps]

ELECTRICAL

I thought I could just reweld the existing electrical plate somewhere else on the frame because it works the way it is but it wouldn't quite fit without jutting out. So I started by cutting the plate up so I could use the existing threads and gaskets for each part.







Using the original threaded tabs for the old regulator I just welded them to the frame. Perfect fit.


Hooked everything up and the bike turns on. Forgot to plug a hole in the ignition and it's filled with beads so I had to get a new one. Key would barely turn.


Then I got a new regulator and rectifier and just welded a plate on to the frame and the parts just bolt straight to it. Probably paint it and scrub it to keep the rust away.


I don't know if this will work. The bike turns on and runs but the rectifier gets warm. On the stock electrical panel things are spaced out with gaskets and some are possibly grounded to the plate. In this case everything is bolted to the plate, which is then welded to the frame. Does anyone foresee an issue with this?

[ampsrampstramps]

EXHAUST
I put a MAC 4-1 exhaust on. It comes with a couple of brackets and bolts so it will fit on various bikes. The brackets are cheese so I made my own to fit perfect.






Getting the bends and marking it to cut down.


Bead blasted.


Tacked on.

[ampsrampstramps]

SEAT


Carboard platypus seat template.


Bent bar to place in the frame with the right curve.


Had some insulation foam to mock up the seat.




Just used a rasp to shape it.




Other option is to use an old skate deck. Cushion the top and bolt to frame.

[Mcwilliams570]

Nice work so far. I like the foam seat you made looks good.

Matt

[luap]

Good work. Sand trick works around a light pole an ALOT of heat an super slow, Or if you have a emtpy welding cylinder you can tack it on then heat it up
If your interested I can ship a hoop out for you 35.00 in the services offerd section

[cabrala]

Project looks cool. That 550 was in damn good shape, but I'm interested in what happened to the exhaust and stock seat. My '78 is missing such features currently as I try to replace it to stock.

Keep me posted if you look to she'd some parts and bring in some cash.

-Alex

[ampsrampstramps]

Good work. Sand trick works around a light pole an ALOT of heat an super slow, Or if you have a emtpy welding cylinder you can tack it on then heat it up
If your interested I can ship a hoop out for you 35.00 in the services offerd section

Ahh thanks for the info. I've got a furnace for melting metal in here. Next time I fire it up I will roast a tube and try it again.

Is that gas tank as nice as the pictures make it look?

Wanna send it to me?

It's almost as good as it looks. A couple of spots where the paint has chipped and rust has set in. If you saw the tank on the 73 450 you wouldn't believe it. Perfect condition after 40 years and 17,000 miles.

Project looks cool. That 550 was in damn good shape, but I'm interested in what happened to the exhaust and stock seat. My '78 is missing such features currently as I try to replace it to stock.

Keep me posted if you look to she'd some parts and bring in some cash.

-Alex

They are yours. Just pay me what it costs to pack and ship +/-. Happy to contribute to a project. The seat is fine. The exhaust has some minor holes but if I remember correctly one of them could be severe soon. I will put some pics up.

[cabrala]

Project looks cool. That 550 was in damn good shape, but I'm interested in what happened to the exhaust and stock seat. My '78 is missing such features currently as I try to replace it to stock.

Keep me posted if you look to she'd some parts and bring in some cash.

-Alex

They are yours. Just pay me what it costs to pack and ship +/-. Happy to contribute to a project. The seat is fine. The exhaust has some minor holes but if I remember correctly one of them could be severe soon. I will put some pics up.

Wow, thanks! I shot you over a PM just to keep your thread about your work and not my parts hunt.

[jgivens]

I'm going to be doing something very similar for my seat on my 550 this winter. Great pics!! Any other tips you have as far as shaping the foam, etc??

[ampsrampstramps]

I'm going to be doing something very similar for my seat on my 550 this winter. Great pics!! Any other tips you have as far as shaping the foam, etc??

Keep in mind this foam wont be in the final seat. Just trying to get an idea for the shape. The rasp works great and doesn't get too messy, an orbital sander with some rough grit should work, or a grinder but it's gonna get messy.

[ampsrampstramps]

Electricity is absolute magic but a real pain in the ass. I prematurely bolted the fuses, regulator and rectifier in. There wasn't enough room to fit it all once I pulled all the other parts up. Welded another plate back in the tail and popped some holes in the frame to run some wires through. If I were to do this again I should have finished the tubing on the frame and filled the whole area under the seat with plate and then organized the electrical.

[JD]

Nice project, given me some idea's on my 1978 CB 550K project,
I salvaged my bike from a guy who had stripped the bike down and never did anything with it, except fill the shelves in his workshop!!!
in fact when i went to buy the bike i loaded it into the back of my jeep, most of it in plastic boxes.
I've just started my project but already spent a bit on original parts, but i need to source a good 4 into 1 exhaust and silencer, any suggestions are very welcome..
Ive being trying to add a couple of photos but there is a Fault code popping up, maybe the picture files are to large?

[Bankerdanny]

If the tank is that nice I would look for a not so nice (paint finish wise, not rust wise) one and sell off yours. You should be able ot make some money on the deal and someone who is keeping or restoring a stock bike gets the benefit of good original paint.

[ampsrampstramps]

If the tank is that nice I would look for a not so nice (paint finish wise, not rust wise) one and sell off yours. You should be able ot make some money on the deal and someone who is keeping or restoring a stock bike gets the benefit of good original paint.

It's not so nice anymore. One of my employees knocked the bike over an hour ago and dented the piss out of the tank. I can't find one on ebay either. Crazy to think the bike has gone 35 years in great condition and just like that... virginity gone.

Nice project, given me some idea's on my 1978 CB 550K project,
I salvaged my bike from a guy who had stripped the bike down and never did anything with it, except fill the shelves in his workshop!!!
in fact when i went to buy the bike i loaded it into the back of my jeep, most of it in plastic boxes.
I've just started my project but already spent a bit on original parts, but i need to source a good 4 into 1 exhaust and silencer, any suggestions are very welcome..
Ive being trying to add a couple of photos but there is a Fault code popping up, maybe the picture files are to large?

Sounds like a nice score! I just got a mac 4 -1 exhaust. Google and you will find. You will probably have to play around with the jets to get it running properly after you make the switch but there is tons of info already on this site if you search that will point you in the right direction. Don't know what's up with the pics.

[cabrala]

#$%*, Nick! I'm sorry to hear about the tank
Can't really do much about it, but I'd be very angry on the inside.

JD, in terms of pictures you will need to log more posts on the site before you can link to or post pictures (if I recall correctly). I think the magic number might be 5, but just keep posting away and trying to add pics every once and a while.

[Garystratos201]

Real bi*** about the tank, You maybe able to push some of it out using air pressure, just be careful and not use to muchh. Then metal finish and bondo........Gary

[ampsrampstramps]

Real bi*** about the tank, You maybe able to push some of it out using air pressure, just be careful and not use to muchh. Then metal finish and bondo........Gary

I'm going to try the hot to cold method I've seen. Hit it with some heat and then cool it off as fast as you can. Sometimes they pop back to normal. I'm sure the paint is coming off too.

[LesterPiglet]

If the tank is that nice I would look for a not so nice (paint finish wise, not rust wise) one and sell off yours. You should be able ot make some money on the deal and someone who is keeping or restoring a stock bike gets the benefit of good original paint.

It's not so nice anymore. One of my employees knocked the bike over an hour ago and dented the piss out of the tank. I can't find one on ebay either. Crazy to think the bike has gone 35 years in great condition and just like that... virginity gone.

Nice project, given me some idea's on my 1978 CB 550K project,
I salvaged my bike from a guy who had stripped the bike down and never did anything with it, except fill the shelves in his workshop!!!
in fact when i went to buy the bike i loaded it into the back of my jeep, most of it in plastic boxes.
I've just started my project but already spent a bit on original parts, but i need to source a good 4 into 1 exhaust and silencer, any suggestions are very welcome..
Ive being trying to add a couple of photos but there is a Fault code popping up, maybe the picture files are to large?

Sounds like a nice score! I just got a mac 4 -1 exhaust. Google and you will find. You will probably have to play around with the jets to get it running properly after you make the switch but there is tons of info already on this site if you search that will point you in the right direction. Don't know what's up with the pics.

It's not as bad as it looks, that dent can be pushed out.

[Tews19]

Subscribed! You have some skills.

[luap]

I havnt tried it but heard about filling the tank with water then putting it in the freezer expanding of the water will push dent out.
Electrical looks good for hiding all the stock components

[ampsrampstramps]

Ha! thanks for the ideas on the dent. Sounds logical.

Stripped Bolt Extraction.
I've been taking some of the casings off the engine to clean them and in the process managed to strip a few bolt heads. Not cool, but a buddy told me try and weld a rod onto the head of the bolt and grab it with a vice grip and twist it out. Sounded a bit hairy but figured it was the only option. The steel bolts go in through an aluminum casing, which melts at a much lower temp, so it was a bit dicey maneuvering around the head of the bolt trying to get a decent weld without melting anything else. It aint pretty but it works. Instead of vice grips I just welded a rod on perpendicular and twisted them right out. Ordered new bolts all around.