Author Topic: CB550 K0 project  (Read 8750 times)

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Offline RSTLESS

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CB550 K0 project
« on: February 05, 2014, 02:45:28 PM »
I picked up a 1974 CB550 K0 back in July of 2013 and I've been meaning to put up a build thread and get some input from the SOHC4 community. My initial intentions were to build a bare bones, with next to no electronics, as lightweight as possible, kick only, cafe racer. These are some pictures of the bike the day I picked it up.
1974 CB550 K0 - Silverback
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Offline RSTLESS

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CB550 K0 project
« Reply #1 on: February 05, 2014, 03:16:53 PM »
I brought her home, got the safety, an old 3/4 helmet, Halcyon goggles, my M2 and started removing the excess almost immediately and added a nice cafe 'X' with electrical tape. (Yes it makes it faster) I also removed the vent tube and replaced with a K&N breather, some pre-planning for velocity stacks.
1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #2 on: February 05, 2014, 03:33:02 PM »
I had some fuel problems in August so I removed the tank and fuel lines cleaned out some rust sitting in the fuel bowl and filter. Since the tank was already off I wanted to take it down to the bare steel and see what kind of shape the tank was in. I started sanding it and the tank looked like it had just been painted over and over different colours so I had it acid dipped. Once acid dipped I fell in love with the bare steel and brazed look so I took some scotchbrite and brushed the steel to shine it up, used some Eastwood Tank Sealant and clear coated to protect the steel.

 
« Last Edit: February 05, 2014, 03:35:03 PM by RSTLESS »
1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #3 on: February 05, 2014, 03:55:42 PM »
With the tank in brushed steel the blue side covers looked pretty odd, so I sanded them down, primed and painted them matte black. The combination of the steel and matte black gave the bike a more attractive cafe 'line'. I also purchased my second bike a 1969 CB450 K2 project that needs a full rebuild. This kind of opened my eyes and changed the direction of my 550 build. With the CB450 needing next to everything rebuilt, I decided to make it my bare bones cafe build and my 550 would become my stock modified build. I swapped the rear brake and mount off the 450 (has more of a classic honda look to me, also smaller) sandblasted the mount, primed and painted matte black, bolts right up to the 550 rear fender, plug and play. Also sanded primed and painted my headlight matte black, and my front disc brake caliper matte black to tie it all in.
1974 CB550 K0 - Silverback
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Offline calj737

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Re: CB550 K0 project
« Reply #4 on: February 05, 2014, 03:55:58 PM »
bike looks to be in very good shape, despite the original paint/over paint. You would do well to very carefully disassemble the bike of the parts you wish not to keep. In their original condition, they have value for many who prefer an original stock condition.

I agree, the brushed bare metal look is very appealing on the tank. I have the same bike, regrettably, it was not a candidate for bare metal.

Welcome
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline RSTLESS

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Re: CB550 K0 project
« Reply #5 on: February 05, 2014, 04:07:14 PM »
bike looks to be in very good shape, despite the original paint/over paint. You would do well to very carefully disassemble the bike of the parts you wish not to keep. In their original condition, they have value for many who prefer an original stock condition.

I agree, the brushed bare metal look is very appealing on the tank. I have the same bike, regrettably, it was not a candidate for bare metal.

Welcome

Thanks calj, very true, and had my bike had original paint I would have left it that way, love the original orange sunburst colour. PS love your build, its one of the 550 builds that inspired me.

I spend a lot of time in a local hotrod shop doing their designs and builds so luckily I knew the value of good quality original parts. I have all of the original parts I'm not using off the 550 and 450 parts all cleaned up and stored for now including an original set of K0 - K2 CB450 exhaust I removed from my 450 when I purchased it in near mint condition. Ill be posting some of it when I get a chance.
1974 CB550 K0 - Silverback
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Offline calj737

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Re: CB550 K0 project
« Reply #6 on: February 05, 2014, 04:11:14 PM »
Must explain that yummy bow tie in the background of your pics.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline RSTLESS

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Re: CB550 K0 project
« Reply #7 on: February 05, 2014, 04:23:52 PM »
Some more pics when I removed the rear fender and tail light. The rear fender was rough underneath so I masked it off and sandblasted the underside, primed, and painted matte black. (I had a couple cans of it, might as well use them)

PS If anyone has a set screw and nut, (the screw with the spring on it for adjusting and setting your front disc brake) for a CB550 I would be interested in purchasing one. As you can see from the last picture the previous owner snapped this one off.

1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #8 on: February 05, 2014, 04:49:45 PM »
Must explain that yummy bow tie in the background of your pics.

That is my first love. A 1969 Camaro RS pro-touring build I have been working on. I bought it off eBay in 2008, drove it for a summer and tore it apart. (I have a habit of doing that) She just wasn't performing up to my standards. Did some sketches for it and some CAD for a full frame to accommodate a 50/50 weight distribution, channeled through the frame and 2" wider front and rear end, picked up a GM LS7 out of a Z06 Corvette, Tremec T-56 Magnum (Corvette ZR1 trans ie. TR6060), sitting on Nitto NT05 12" rubber and wheels in the rear on custom Bonspeed wheels 19", 18" wheels with 8" NT05 rubber up front. Wilwood big disc brake kit, Bears custom rear end, full AirRide system, 4-link rear end, flaming river rack and pinion steering, and tons more good stuff. She's an ongoing project that now requires 20K for a supercharged LS7 build to get her close to 1000 engine hp, 10k on interior, and another 10k or so on Carbon Fiber and body mods. When she's done I plan testing her out in autocross racing to get her properly tuned in and maybe make a few more changes depending on how she does.


1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #9 on: February 05, 2014, 05:15:46 PM »
Unfortunately I live in a colder climate than most and in mid November riding was spotty and with less time to do the ton and more time to play I came up with a design for a bracket that turns my iPhone into a digital speedometer with GPS navigation, a 'GoPro' with audio and video capabilities, with up to the minute reports on weather, and my favourite SOHC4 articles and builds. Its lightweight, reduces the number of cables needed and cleans up the front end.

If anyone is interested I can make these for any bike. The design works with whatever phone case and belt-clip setup you want to use. I have 2 designs for the CB550 one with stock, drag, clubman, or other top mount bars, the other is for clip-ons all with the stock top triple tree. Pictured on the bike is the design that works with the top mounting bars. The CAD rendering is design 2. I can readily make these and I am just waiting on a quote for 250 units. Any ordered would be CNC cut from aluminium, with optional black anodizing.
« Last Edit: February 05, 2014, 05:18:08 PM by RSTLESS »
1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #10 on: February 05, 2014, 05:20:56 PM »
This is the CAD I did for the second design for use with clip-ons and stock top triple tree.
1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #11 on: February 05, 2014, 05:32:14 PM »
I took a vacation and went down to Florida to visit my parents in late November and used it as an excuse to check out Dime City Cycles. I can't say enough about these guys, Kara and Chris dropped what they were doing and took the time to help me figure out what parts I actually wanted for my 550 build. Needless to say I left with a box full, and a lighter wallet. (lighter wallet = lighter rider, therefore faster bike?) Picked up a full setup to change over to vortex clip-ons with new shorty levers, new switches, DCC bar end mirror, slim barrel brown grips, new headlight mounts, and a new thottle.

1974 CB550 K0 - Silverback
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Offline RSTLESS

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Re: CB550 K0 project
« Reply #12 on: February 05, 2014, 05:40:04 PM »
Some pictures of the projects as of January 2014. Can you ever have enough projects?

The front forks weren't easily removed, and looks like I need new fork seals. Judging by the fluid that came out of the forks they haven't been changed in a while. Any one have suggestions on where to go in Ontario, Canada for fork seals, wheel bearings, and a tapper roller bearing kit for a cb550?
« Last Edit: February 05, 2014, 05:43:30 PM by RSTLESS »
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Offline calj737

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Re: CB550 K0 project
« Reply #13 on: February 05, 2014, 05:47:51 PM »
AllBalls tapered bearings for the steering head.

Re forks: two choices here, Progressive springs OR cartridge emulators. Progressive springs maintain stock look, emulators upgrade the look. Both deliver great upgrade in handling. I used Progressives on my 550, have Cartridges in my 500 via GSXR front end.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline RSTLESS

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Re: CB550 K0 project
« Reply #14 on: February 05, 2014, 06:05:31 PM »
AllBalls tapered bearings for the steering head.

Re forks: two choices here, Progressive springs OR cartridge emulators. Progressive springs maintain stock look, emulators upgrade the look. Both deliver great upgrade in handling. I used Progressives on my 550, have Cartridges in my 500 via GSXR front end.

Thanks, cartridge emulators look pretty cool. Ill look into it.
1974 CB550 K0 - Silverback
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Offline SOHC4 Cafe Racer Fan

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Re: CB550 K0 project
« Reply #15 on: February 05, 2014, 06:07:53 PM »
RSTLESS,

Great call on making the 550 a restomod. It's too clean to cut up. I like the iPhone bracket but I'm using aftermarket upper triples.

+1 as to AllBalls for the seals and bearings. I have the Race Tech springs and gold valve emulators. It's a great upgrade for a restomod.

Looking forward to more on this.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline RSTLESS

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Re: CB550 K0 project
« Reply #16 on: February 05, 2014, 06:14:37 PM »
With the font end apart I decided to sandblast the wheels, brake parts, lower forks, and a few other parts for powder coating or paint. I got tired of looking at the solid disc and these 550's were known to have brake issues to I thought I'd take this opportunity to CAD up the front disc and CNC some cross drilled holes to improved both the aesthetics and functionality while reducing a couple ounces.

If anyone is looking to have their stock CB550 disc machined, cross drilled, slotted, or customized let me know. I can make the CAD and have it made to order.

I also removed the rear sprocket cover to make up CAD to CNC a pattern. Thinking of making some 1/2 holes and welding mesh in behind and carry this on into the rear drum cover and some other parts as well. Any have any thoughts on drilling holes in your sprocket cover or drum brake cover. I've seen it done before, sometimes tastefully, sometimes it looks like someone got a new drill.

Should the inside of the sprocket case look like the last 2 pictures? I found some pieces of a chain in a pile of chain lube and I'm wondering if there is a seal gone.
« Last Edit: February 05, 2014, 06:21:39 PM by RSTLESS »
1974 CB550 K0 - Silverback
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Offline calj737

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Re: CB550 K0 project
« Reply #17 on: February 05, 2014, 06:26:50 PM »
"Should" it, no. But they all do until cleaned up and refurbished. The sprocket/side cover is open from the rear, and the chain slings goop which catches debris, which builds up over time, which... Well, you get the picture.

If you remove the front sprocket, be sure to re-install it with Blue LocTite. That whole area deserves to be cleaned back to super clean. A new chain, and perhaps sprockets F/R might be well worth your purchase. Also, double check the case at the 9:00 edge of the chain. This area often has some damage to it from a broken chains or poorly adjusted chains.f damaged, it can be repaired.

The more you remove these covers, the more cleaning you are in for. But hey, after 40 years, what vehicle doesn't need some cleaning? At least there's no fenders, grills and hoods to crawl around to get to the dirty areas. Wide open access, Baby!
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline RSTLESS

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Re: CB550 K0 project
« Reply #18 on: February 05, 2014, 07:16:44 PM »
I was wondering whether to replace the chain and sprockets. They look fine, but they are worn. And I do want to create a little more torque so maybe Ill bump up the rear sprocket a little, throw in a nice gold/brass chain. Any suggestions for increased torque and power off the line?

I'm also considering making a partial sprocket cover to original specs that leaves most of the sprocket case open but allows for a starter cover to be re-attached and a little more protection for the wiring.   
1974 CB550 K0 - Silverback
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Offline SOHC4 Cafe Racer Fan

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Re: CB550 K0 project
« Reply #19 on: February 05, 2014, 08:10:50 PM »
Since you have access to a CNC, I would suggest slotting your rotors in addition to cross-drilling holes. Also, take a look at Raccia Motorcycles CB550 build for a cool idea on opening up the front sprocket cover.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline calj737

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Re: CB550 K0 project
« Reply #20 on: February 06, 2014, 03:19:55 AM »
Regarding torque tuning changes: you can do it with carbs, cams or sprockets. Each has it's Achilles heel. Sprockets: lower torque, loss of high end speed. Carbs: low end/mid range torque, high end lean. Cams: expensive, and high end loss.

Everything is a trade off. All depends upon your style and budget. My best recommendation would be really good, clean and perfectly tuned carbs, MRieck stage 2 head, and fresh sprockets. And a good exhaust. You may not have a real "dyno" beast, but the seat of the pants dyno will be very impressed.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline RSTLESS

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Re: CB550 K0 project
« Reply #21 on: February 06, 2014, 07:11:36 AM »
Since you have access to a CNC, I would suggest slotting your rotors in addition to cross-drilling holes. Also, take a look at Raccia Motorcycles CB550 build for a cool idea on opening up the front sprocket cover.

Great idea, I was considering slotting and I left some space between the cross drilled hole pattern in case I want to add it in later. I may have to revisit that idea.

Its funny how many times I've seen this build on Bike Exif and other sites, but I have never noticed the sprocket cover. That is beautiful. I might have to step it up and add in my own touch.

Thanks for the info calj, more awesome stuff to look up and spend my money on. As far as a cam swap, I've heard of a lot of people using the 650 cam. When I pull the motor I was going to do a big bore kit and possibly do the 650 cam swap, does this require a 650 head too?
« Last Edit: February 06, 2014, 07:15:07 AM by RSTLESS »
1974 CB550 K0 - Silverback
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Offline SOHC4 Cafe Racer Fan

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Re: CB550 K0 project
« Reply #22 on: February 06, 2014, 07:22:36 AM »
No 650 head required for the cam swap. If you are going to stay with an analog tach, you will also need a 650 tach drive and 650 tach. Otherwise, you can plug the tach hole and go without a tach or with a digital tach.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline RSTLESS

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Re: CB550 K0 project
« Reply #23 on: February 11, 2014, 11:18:20 AM »
While I was checking out racetech's catridge emulators and springs I found TNK fork tubes in copper, gold, black, and chrome finish. I have been looking for brass/gold tubes for this build but they don't seem to make them in a 35mm tube for the CB550. Anyone seen any around or know where I can get some to fit my 550? My tubes are near perfect with the only markings being from the clamps with minimal rust, do you think they can be powder coated brass/gold without causing any issues?
1974 CB550 K0 - Silverback
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Offline calj737

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Re: CB550 K0 project
« Reply #24 on: February 11, 2014, 07:48:11 PM »
Yes they can be. Powder coating is very thin and almost not measurable.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis