"Patina" The 1973 CB175 Cafe Racer

[1sttimer]

Well Guys, I guess I've taken advantage of this forum for long enough and I should start a build thread. I am a first time builder from North Carolina and my name is Greyson. I've learned a TON (no pun intended) from this forum over the past couple of years. I wanted to start small, though I've ridden dirt bikes and 4-wheelers all my life. From a build perspective I wanted something simple.

I found a 1973 CB175 on craigslist from a guy up in King, NC in "running" condition for $600 bucks. He wouldn't take any less and I was itching to get started so I bought it, wise or not. When I picked it up, it looked like this:



This was over a year ago. The bike was entirely stock and had 99% of parts, including the airboxes and side covers. The guy just replaced the cam shaft which was good. It also had 2 brand new EMGO shorty's included.

After I got the bike home I parked the thing in my dining room and got things looking like this:



Long story short, I tried to get the thing running decently and had a guy put some new rings in along with getting the wiring sorted out. That was the BIGGEST MISTAKE OF THIS PROJECT. After his work, it looked the same, minus a new headlight and taillight:



For the life of me I couldn't get the thing running right. After the throttle sticking on me a few times and having other issues, I just wanted to get my hands dirty and tear the thing down. When I did, I found the guys' mistake...a bent oil ring out of its seat and a horribly scored cylinder after a fresh hone.



So, my story will begin here. I have gotten a lot done since this point so I'm going to use the next few days to backfill my work done and build up this build thread. I have learned a ton from this thread and appreciate all you guys do to help out. As I move forward I'll post more pictures, as I know we all love picture-heavy threads!!

Thanks guys and enjoy the ride!

 

[1sttimer]

I should also mention that I am trying to build a ground up cafe racer...I'm doing a custom seat built by a guy in Burlington mounted to a fairly stock frame with some welded supports for rigidity. I'll be running velocity stacks from steel dragon eventually with a 2-1 built by a guy here locally and a DCC "shorty" muffler.

I'll have a 5-3/4" BATES light on the front, a cateye light on the back, DCC headlight ears, DCC headlight/kill switch all wired up with a Sonreir custom wiring harness (eventually).

 

[1sttimer]

My next step was to remove everything on the bike because I essentially want the thing to behave/function/act like a new machine. The bike had 5600 miles on it when I got her.

Starting the stripping process:







I'm going to run kick only so that hunk of metal will be gone to free up some weight:



I started de-tabbing the frame and got carried away in a few places. I still have structure but as you will see later, I'll be adding a few cross members to strengthen things up a bit.



SO now I'm to the point where I need to start deciding what I will be keeping and what I will be tossing. I have zip-lock baggies of every nut and bolt that came off of this thing. I'm OCD like that. I have a handful of parts I won't be using so PM me if you would like something. I possibly have it.

My next step is going to be tearing down the engine for paint. I want this thing to be nice and clean when I put it back together.

Thanks for watching!

 

[1sttimer]

Soooo here's the thing. My dad always told me "a man's got to know his limitations." - Clint Eastwood.

I certainly know mine. However, I wanted to learn as much as I could from this project with it being my first one. I would like the second to go twice as fast because I won't be making the same mistakes.

BEFORE ANYONE ASKS ME WHY I SPLIT THE CASES, I HAVE NO FREAKING IDEA. But I learned a ton in the process. I also learned that I have no clue how to put it back together and that I should have taken it apart sitting upside down on the studs so things didn't fly out at my face.

Mighty dirty in there. Where in the world did this guy ride this thing???



Everything looked super clean on the inside, almost like it was never touched.



Like I said, I'm going to eliminate this. You will see later that CrazyPJ helped me out with a starter block off plug that is amazing. He does great work. I wish I knew all of the things he is capable of.



It took me a while to figure out the trick to getting the oil filter housing off. That 8mm bolt trick seemed to do the job once I bought that special honda tool to get the lock nut thing off.



On to the cases. As I said, I have no idea why I did this. I suppose I wanted to clean everything from top to bottom...another spot where my OCD kills me. Looking back on it I should have taken some degreaser, turned the engine upside down and went to town with a pressure washer.

 

[1sttimer]

Took some heat to get the cylinder head off of the cases, and the same for getting the cylinders off the head.



Gaskets look brand new...means someone was in here recently right??



So here's that nice chunky score mark that the mis-seated oil ring caused over the first few miles I ran the bike. This ended up costing me a new sleeve along with a 1mm overbore, new pistons, new rings and a hone in re-assembly. Keep in mind this happened over like 3 miles of riding. Gnarley. I got some money back from the guy on that one.



Shot of the valves. I actually kept the valves installed the entire time. My mechanic is going to check the clearances for me when putting things back together.

 

[1sttimer]

Sorry, I'm getting to the cases....



Okay, here's my transmission. Everything looks mice and tidy now, until I take everything out...still not sure why I did that.



I kept all of the shafts and gear assemblies in tact so there's some sub-assembly that won't have to happen. I didn't make things overly complicated for the guy putting it back together...I hope.

 

[1sttimer]

Ok so now I start to make a little progress. I used Duplicolor silver caliper paint for the cases/clyinder and VHT wrinkle black for the head and head cover. It took me about 3 tries on the cylinder head to get the wrinkle paint right. I am very friendly with aircraft stripper.

For prep I soda blasted the cases after degreasing with Purple Power. I glass bead blasted the outside of the cases to get some gunk off but I stuck with soda for the head. I blasted the head with the valves installed. I made sure to rinse, pressure wash, rinse, soak multiple times to make sure I got the glass beads from the cases. All clean now.

Here's a mock-up of the paint job. Overall I'm satisfied with it. I hope the paint doesnt chip off too quickly. If I were to do it again, I would leave the bottom end together, de-grease and pressure wash and assemble without paint. As the engine gets dirty I bet it would look a lot better that dirt over paint. We will see.

Sneak shot of the engine mockup before assembly...

 

[Barnburner]

Good luck with the project. My CL175 is bored 1.0 over and I love the extra grunt. With a full rebuild and proper tune like some others here on DTT (e.g. Texasstar's CB200) these little bikes can rip to 80-90+.

 

[1sttimer]

BarnBurner, thanks for the luck...how does yours feel around 65? What kind of RPM's are you pushing? I didn't figure this thing for a long distance interstate goer but for 5-6 mile jaunts could it handle it?

 

[Barnburner]

Mine falls on its face in 5th gear around 60-65, but on stretches I can get over 70. That might be fuel flow issue, though. I generally keep it in the higher rev ranges (no specifics since I don't have a tach) in lower gears and do short rips around town like you mentioned (5-10 miles max). From what I've seen on this forum and others, these little motors seem to perform better at high RPMs. It is definitely not a distance rider - I almost got blown over by a particularly strong gust the other day - but it sure is nimble!

 

[1sttimer]

Could be a carbie issue?

I live about 3 miles from work so I can't wait to have this thing winding up back and forth.

 

[1sttimer]

I also got to work on the hubs. I was going to powder coat the hubs but could not get the cush drive out so I decided to use Epoxy paint. That stuff is amazing. I prep the surface by media blasting and then wipe down with Xylol (Xylene). The Black epoxy paint works wonders. I can't remember the brand I used but the can is in my garage somewhere. I could find out.



When I pulled the spokes I kept them separate front to back and then there are 18 90-degree spokes in the front and 18 >90 degree spokes as well. Same for the back. From what I saw, spokes threaded from the outside of the flange through to the inside are >90 degrees. You can see the button when fully threaded and looking at the outside of the flange. Spokes threaded from the inside to the outside of the flange wall are 90 degrees. You can see the button on the inside face of the flange. I thinkkk....



I also spent some time polishing up my spokes. I found this set of 5 polishing wheels for a 4.5" grinder at HF that I used that worked very well. I used the 600 only and I will finish off with some 1500 grit paper then move to cutting compound and so on. I don't want them to be perfect...her name is "Patina" after all...



I have sent my nipples off to o1marc to be powder coated. Cant wait to see those. I also got some new wheel bearings from All Balls Racing and installed those. Simple product but they came with some extra seals and I have no idea where those go...



Then I went to Western Hills Honda and bought some new actuators and new nuts and bolts for the hubs. I love the way they turned out.

 

[1sttimer]

Well i finally finished up the front and rear wheels. I have 18 more spokes to polish and then I will be ready to lace them back up. First of all, I want to put a shout out to o1marc here for powder coating. He shot my nipples black and also my rims. I dont have a photo of the rims quite yet but I'll get that on here ASAP. He did a freaking amazing job and has super fast turn-around times. And he responds to messages almost immediately...that's always a plus in my book.

Here's the finished front and rear hubs and the triple tree blasted and ready to be rattle canned (saving some cash).



And here's the nipples I mentioned...

 

[1sttimer]

Ok, and here are the wheels, polished spokes and rims (also by o1marc). It took me about 8 freaking tries on the rear wheel to get the lacing right. Then when I went to the next wheel I did it in about 15 minutes.

Also, for anyone who wants a simple, easy to use tutorial on wheel lacing, here it is:

http://www.xs650chopper.com/2009/12/how-to-lace-a-wheel-from-scratch/

That link was given to me by haircuttergirl. Thanks!

 

[1sttimer]

So, I've been really excited to get to this post...I have been working with a guy named James in Burlington, NC at Riverside Antiques Moto Co. He's a super guy and does some really cool work. I had him give his best shot at a one off seat made of fiberglass with a carbon fiber overlay. He did a freaking sweet job. Here's his progression. Since I grinded the stock seat support off the back of the frame, he welded me a nice little cross member right between the rails. He ended up bolting a hinge to the downtube, bolted that to the seat and we used a clevis pin on the middle to hold the back end down.

Here's his foam mockup...I freaking love how low and sleek this thing is. I'm going to tuck an antigravity battery right up underneath.




Here she is after some fiberglass laid down. The front reveal is going to turn out pretty nicely. I'm going to make my own pan out of aluminum and have it wrapped in brown vinyl.



This is the first coat of resin over the carbon. As you can see it soaked right through. He ended up putting 5-6 on there before buffing and waxing.



Here's the seat once the resin started to build up. This is before any sanding or buffing.

 

[1sttimer]

From here he went ahead and got it mounted with the hinge:



He used the shape of the tank to mold the lines with the seat. Thing looks killer...



And after hours of buffing and polishing, I ended up with this sweet seat ready to roll and mounted up.





He also mounted me up a nice little cateye tail light so no one rear ends me when I get this thing back on the road.

Just to put in a little plug...he did all this for very cheap. If you're local look him up. I'll take some more pictures of how it's mounted soon.

Thanks for looking!

 

[DoTheTodd]

Those wheels came out awesome. I love the black nipples, it's a nice touch.

 

[Ryeson]

I have a 72' cb175 im tearing into, your build has given me ideas gallore. Thank you. Your bike looks great.

 

[1sttimer]

Those wheels came out awesome. I love the black nipples, it's a nice touch.

Thanks, Todd. o1marc coated them for me for a great price...without the spokes. He fabbed up a way to do it.

I have a 72' cb175 im tearing into, your build has given me ideas gallore. Thank you. Your bike looks great.

Thanks Ryeson! The hardest part was figuring out the seat. It seemed like the whole bike hinged on the seat mounts on the frame. I have everything basically done, I just have to throw it back on the bike after I get the frame coated. It should come together fast.

 

[Ryeson]

This is where i sit at the moment, rolling chassis. When i get home im going to drop all suspension and motor. Keep the pictures coming, cant wait till your bike is complete.