Topic: '71 cb500 (re)rebuild thread: fabricated new MAC baffle and plate mount

[davis96]

Hey guys,

This is the second build of my second SOHC bike, my 1971 cb500. The other build thread is in here somewhere if you have any questions about the first rebuild. 
A year ago, 4 days after I sold my 350f, I bought this for $300 from craigslist. It had 9k miles and was in non-running, pretty crappy condition.
BEFORE:


THEN:
I did a cheap/somewhat fast rebuild the first time just so I could get out on the road:


THE (RE)REBUILD
I used a very minor head gasket leak as an excuse to take the 3 months of summer to do an equally cheap, but more thorough and thoughtful re-rebuild. I am currently in my last year of law school so I am as poor as poor students come. My summer internship was of the unpaid variety, so I couldn’t afford to do things in a manner which  some deem to be the “right” way (i.e. replace instead of polish/rebuild, powder coat instead of paint). But elbow grease is mostly free, and I think I ended up with a good result. My goal was a clean, mild café-style daily rider which retains a general quasi-period-correct look (nothing too modern).

I opted for the instant gratification, start-to-“finish” build thread in lieu of the day to day updates style, so after I list modifications, there will be a lot of pictures. I'm almost certain I'll forget some stuff, but for everyone's information, here goes:

FRAME
-Tab welded to center stand to limit travel
-Frame/center stand/swingarm/top and bottom triple trees were stripped and painted with black Rustoleum appliance epoxy
-All other frame bits (footpegs, battery box, etc etc) were given a similar appliance epoxy paint treatment

TANK/PAINT
-“Honda” tank emblems shaved, dents fixed
-Painted tank and side covers with Rustoleum appliance epoxy, allowed to cure
-Tank/covers wet sanded up to 2000 and cleared with SprayMax 2k two part rattle can clear
-Walmart chrome door trim added to tank’s edges ($8 for 18 FEET)
-NOS Honda CA72 wing emblems applied to tank with outdoor double-sided tape

ENGINE
-Head pulled, cleaned, full gasket set installed (except base gasket)
-Polished the normal covers (tappet, breather, left/right side, etc)
-Painted the rest of the engine (Duplicolor ‘aluminum silver’)

CARBS
-Basic carb clean/rebuild/bench sync
-Light polish on tops and bowls
-Factory “velocity stacks” pulled from the airbox and used by themselves because I’m lazy and want it to be easy to pull and re-install the carbs (spare me a lecture on the evils of open stacks, I am aware of their disadvantages)
-#115 main jets from dime city cycles

ELECTRICAL
-Replaced inline-type with fuse-type main fuse holder
-60s/70s Sportster taillight
-I mucked up my headlight bucket pretty bad, so I replaced the stock unit with a smaller 55w light made for off road trucks (from Harbor Freight), generic toggle switch used for headlight and mounted out of sight on the back of the new bucket.
-As a result of changing the headlight assembly, there was no room inside for all the wiring, so I hid it all under the tank.
-Replaced both the horn and starter buttons with cheap switches from Radioshack (no problems yet)
-Neutral/oil pressure idiot lights made from $2 Radioshack LEDs, and moved inside the tach.

SUSPENSION/BRAKES
-Converted back to single disc setup for ease of bleeding and selling the parts to helped finance the rest of the build.
-New fork seals
-Fork lowers, brake pivot polished
-Caliper rebuilt/repainted
-Stock headlight ears eliminated, replaced with 10 dollar Emgo Ebay special headlight brackets
-Chrome plumbing pipe used to make covers for Rusty/nasty area on the upper forks between the trees after treating/painting affected area
-DIY fork gaiters from JCWhitney  (trimmed down offroad truck shock covers)
-No name (possibly homemade?) clip-ons from ebay, refinished
-Shocks disassembled, chrome and aluminum polished, springs painted with (you guessed it) appliance epoxy
-New gold 530 chain (kinda splurged on this, but the aesthetics of the gold chain is one of the few things I was willing to pay more for)

PICTURES:










































After appliance paint:

Sanded (2000)


This clear is awesome:

Bit of orange peel, couple runs, but I’ll live and eventually get around to sanding out the imperfections and buffing:



Reassembled:



 




Still left to do: New grips, do something about those awful rusty exhaust header flanges. Feel free to ask any questions you might have, and let me know what you guys think!

Thanks,
Davis

[fastbroshi]

What chain is that?  Looks like an o-ring version.  Those are usually too wide and end up eating into the seal at the countershaft sprocket's 10 o'clock.

[davis96]

What chain is that?  Looks like an o-ring version.  Those are usually too wide and end up eating into the seal at the countershaft sprocket's 10 o'clock.

I got it from ebay:

I made sure that the description specified that the chain was a non-oring type

[fastbroshi]

Cool.  Overall it came out great.  Especially the paint,  from those pics I'd bet a lot of people would be happy with it

[davis96]

Cool.  Overall it came out great.  Especially the paint,  from those pics I'd bet a lot of people would be happy with it

Thanks I appreciate it. Soon I'll get around to snapping some actual decent pics of the final product, maybe after I get my new grips, master link for the chain, and get this thing out on the road for real

[lucky]

What a beautiful job you have done!!!

[Mcwilliams570]

Nice job that you have done. The paint looks like it came out really nice. I had to laugh at one of your pictures I saw a blue exercise ball my wife uses those too they drive me nuts. She leaves them all over the house they are fun to kick around at the cats when they are sleeping though

Matt

[Cheffish]

Looks awesome man

[toytuff]

 

Wow! Very well done!

She looks fantastic.

tt

[davis96]

Wow! Very well done!

She looks fantastic.

tt

Thanks for all the kind words. Unfortunately I went out riding yesterday and lost my freshly painted and cleared right hand side cover, such a bummer. It was such a hassle to paint these pieces, replacing the one I lost and repainting the new one is almost not worth it. I am going to go out and try to find it out on the road, hopefully it is not completely destroyed.

[SOHC4 Cafe Racer Fan]

I feel for you.  I lost one of my 750 painted covers by way of a thief at the Int'l Bike Show a couple of years back.  I could not believe another motorcyclist would do such a crappy thing.  I would have paid some good money to catch the guy and beat him senseless.

[davis96]

I feel for you.  I lost one of my 750 painted covers by way of a thief at the Int'l Bike Show a couple of years back.  I could not believe another motorcyclist would do such a crappy thing.  I would have paid some good money to catch the guy and beat him senseless.

Yea it really bothered me at first. But like all things, I've gotten used to it to the point where my lack of side covers doesn't keep me up at night. I think I'll just run it like this with no side covers for a while until I come up with the motivation necessary to procure and repaint a replacement... Maybe I'll paint the battery so it doesn't stick out like a sore thumb.

[thebearded1]

Bike looks great! I'm thinking about painting my rear springs as well.  How well is the appliance epoxy paint holding up on them?

[davis96]

Bike looks great! I'm thinking about painting my rear springs as well.  How well is the appliance epoxy paint holding up on them?

They still look great, I wasn't sure if they could handle the compression and extension that the spring undergoes, but they seem unaffected by it.

[davis96]

So the other day while i was riding, the baffle apparently made its escape from my MAC muffler. This made the exhaust run like crap and sound like diarrhea. I didn't want to spend $50 on a new one so I made one from stuff I had laying around: a piece of 2" exhaust tubing, a little exhaust reducer, and the end cap was made out of an old honda horn I tore apart (it just happened to be exactly the right outer diameter).

The inlet side of the baffle seals to the inlet of the muffler can, and I made louvers which direct a good portion of the exhaust gasses to the outside of the baffle, which then have to travel through stainless steel wool and through the various holes toward the outlet side of baffle before they can exit. I'm no engineer but the ideas behind the design seemed sound (no pun intended) so i went for it.




quick coat of engine paint to prevent corrosion, wrap with stainless steel wool, then weld the whole deal into the muffler

[davis96]

Also got a chance to cut down the stock plate/taillight mount to fit my needs now that I am running a sportster taillight:

[Viktor.J]

Really sweet build and a nice ride ! I have actually saved pictures for motivation and inspiration to my bike 

But when you had the original headlight mount /fork ears, was there any interfering with the clip-ons ?
cause im thinking of use the combination original fork ears and clip-ons, but dont know how "low" i can lower the fork ears before they stops at the "lower triple three" ?

Once again, a really nice bike and a super job !

[davis96]

Really sweet build and a nice ride ! I have actually saved pictures for motivation and inspiration to my bike 

But when you had the original headlight mount /fork ears, was there any interfering with the clip-ons ?
cause im thinking of use the combination original fork ears and clip-ons, but dont know how "low" i can lower the fork ears before they stops at the "lower triple three" ?

Once again, a really nice bike and a super job !

Thanks for the kind words viktor. The stock headlight ears were cut to accommodate the clip-ons. I cut about half of the total size needed off the top of the ears, but I also wanted to lower the entire assembly (and the headlight) some as well, so i cut the other half out of the bottom of the ears, so that they would hang over the bottom triple tree a bit more. Hope that makes sense, here is a simple illustration of what I mean: the black outline is the original for ear body, with the original cutout for the bottom triple tree, and the red represents how I cut it.