[mayerjw2]

Hey everyone. I've been hovering around the forum for awhile now, reading build logs, getting tips and tricks from you all, and generally learning as much as I can about Honda Twins! I've posted questions here and there but finally I think it's time to start a build log...

This project is a joint effort between myself and close friend Tony (one of these days I'll convince him to join the forum at which point he'll hopefully help in updating this log). As far as our qualifications to work on these bikes, they are few... I have a couple degree's in mechanical and manufacturing engineering and yet spend most of my working days (designing industrial robotic systems) wondering what exactly they taught me in school... Tony is a graphic designer with a love for motorcycles. Hopefully that means we end up with a great looking bike - unfortunately that means if it doesn't run, nobody's blaming him :shock: Needless to say I intend to lean heavily on you all and your experience...

The bikes: We picked up a 1975 CB360 parts bike (engine case donor...), and a 1974 CB360 that's in decent shape. We've had a headache with title issues (full story here:frame swap 74-75). So now the plan is to rebuild the '74 motor with the semi-titled '75 engine cases, restore the rest of the bike and apply for a new VIN from the state...

Okay, okay, but what about pictures? Here's what we're starting with:

Now I've been trying to figure out the exact model of this bike, it appears to be a '74 CB360T due to the front disc brake and black points cover, but to put that idea to rest here are the VIN plates

So it seems to be a plain old CB360 with several of the 360T amenities. Feel free to correct me!

Next up is the concept pic. Here's where having a graphic designer on the team helps quite a bit:

So basically a resto-mod I suppose. This is our actual bike with some photoshopped parts/paint on it. Obviously we're missing quite a bit (front fender, rear brake light, rear fender, etc...), but this should get us started! I'm not a fan of repainting over good original paint. Thankfully (or not) our paint is in rough shape, so a custom job it is...

We've been working for a little bit now, here are some progress pics:

 

[mayerjw2]

(That's Tony)

(And that's Tony's latest wheelchair design...)

So we've torn everything down to a bare frame. Don't have a photo but I'm sure everyone's familiar with what that looks like around here, yeah?

We're in the process of taking apart the motor now. We're going extra slow trying to understand how each part works, taking plenty of photo's and trying not to mess things up... It's amazing how great it felt fully understanding how the clutch works.

We're getting close to splitting the cases, going for a complete rebuild. In my next post I'll probably start picking everyone's brain with rebuild experience... We're excited about the project, slightly terrified about rebuilding a motor, and moving full steam ahead either way!

-Jake

 

[mayerjw2]

We're long overdue for an update. We've been working steadily on the bike but I've been waiting to update the log until we had some good pictures to show or ran into an obstacle we couldn't overcome.

Most of the past 2 months were spent tearing down 2 engines. We recovered the top case from the donor engine and have turned the corner from the dis-assembly phase to the cleaning/restoring, and (hopefully soon) rebuilding phases. Here's the disassembled engine with the donor top case:

So with the 360 engine, I've come to learn that the cam chain tensioner design unfortunately hasn't held up well to the test of time. The slipper and guide are discontinued and sadly nothing is offered aftermarket for this problem. The cam chain guide was snapped in our good engine (likely why it was parked) and the one in the donor engine was badly worn. The slippers for both would've worked in a pinch, but we decided to bite the bullet. We were able to track down a NOS slipper from the Honda dealership network. The guide on the other hand was much more difficult to find. Luckily there's a guy not too far away with a stockpile of old Honda parts and bikes. We dug into a 360 parts motor he had laying around. 1 hour and $20 later, we ended up with a practically brand new guide as well as a solid slipper (pre-recall style though...). We now have a collection of sorts of these hard to find components:

We decided to get started on cleaning the aluminum covers we planned to polish. The plan is to paint the cases, jugs, and head with the dupli-color engine enamel (semi-gloss black) and polish the rest of the covers for a shiny contrast. The supplies were purchased:

The degreasing began:

 

[mayerjw2]

We got excited at this point, so after stripping, wet sanding, buffing and polishing we ended up here:

Here's a side by side with parts from the donor engine. The light's pretty bad, but the contrast is still remarkable:

They aren't perfect, but for our first time with the process, we're pretty happy with the results. This afternoon, I'll be dropping off the cylinders, pistions, and head at Bore-Tech to see where we stand. Crossing fingers for needing simply a hone, fresh rings, and maybe a fresh lapping of the valves with new guides. Thankfully if we need to bore, our engine is in good hands. Here are the parts as they stand now:

In the meantime, plenty of wet sanding and buffing to keep us busy. Hopefully while those parts are at the machine shop we can finish the covers and get ready to prep the cases for paint. Still need to buy new oil seals and gaskets but most everything else internal looks great. When it comes time to rebuild the bottom end (hopefully sometime in February), we'll need all of your expertise and help!

 

[dtsmjr8dan]

A tip for your polishing:
As you polish, go one way, then 90* with the next finer grit.
When you use the polishing compound (mother's or autosol) do the same with polishing strokes.
Looking good so far.

 

[mayerjw2]

Hey jr8dan, appreciate the tip. We'll be getting back at the polishing tomorrow night, so I'll take your advice and we'll see how she goes. Top end is at bore-tech (cool place by the way - i'll post pics of the work they did and give them a shoutout when everything comes back).

In the meantime, I've recently finished a book by William Rosen called, "The Most Powerful Idea in the World: A Story of Steam, Industry, and Invention". Anyone read it? It's a very in-depth history of the development of steam power including all the key inventions that were critical steps along the way. It broadly tackles the importance of the patent system to innovation and credits this system (in the context of the story of steam) as the catalyst to the industrial revolution. I though it would appeal to my mechanically inclined/interested brethren here at Hondatwins. Our UK friends may find it particularly interesting as the bulk of the story and many of the key players were your countrymen.

The book also sparked (pun!) my interest to learn more about the internal combustion engine's history and development. Does anyone have a recommendation?

 

[mayerjw2]

No readers out there huh? Well consider that a standing request if anyone has any recommendations.

Got back to some sanding and polishing tonight. Took jr8dan's tip, added an extra fine grit of wet sanding and here were the results:

Whoa!

Starting the process of cleaning up the cases and prepping them for paint. Need some help here though:

I think this is the neutral sensor, correct? How do I remove it?

 

[mayerjw2]

Hmm... I was looking over the parts fiche for the engine and I couldn't find that part (yellow arrow above) called out. My concern is exposing an electrical switch to water and cleaning solvents as we prep the cases before we mask them and prime/paint. Any help out there on this one?

edit: I finally found the switch on the alternator page of the fiche. Unfortunately it doesn't clarify how it's mounted. Help!

 

[barnbiketom]

look at this pic. it is pushed in!! there is a hold down that was on where the one screw hole is..like a distributor clamp????? you must have removed that earlier! It should now pull out, but the o-ring may hold it in pretty hard, but should be replaced anyway..so give it a turn and yank.. spray it with blaster or something.. it should come out.

 

[combustioncafe]

Nice to see a fellow Cincinnatian bringing another old Honda back to life. (It's nice that we live so close to Boretech, right?) Those engine cases are looking great. I'm in for updates on your build. I'm currently working on a 71 CL350 myself, hoping to be done by June.

When you get your 360 done, run down to Fuel for Cars & Coffee sometime (Saturday mornings). Also, if you ever need any wrenching help from a novice/ameteur, let me know :lol: .

 

[mayerjw2]

Quick update tonight: barnbiketom, you were right! After a bit of "persuasion" it came right out. Thanks for the tip!

What side of town are you on combustion? And how's the 350 coming? Got a build log? I'm an amateur right there with you sir, blind leading the blind over here... Thanks for the kind words.

Parts are still at boretech, though I got some okay news from them. The head is in decent shape except I'll be replacing both intake valves with stainless steel replacements. Cylinders and pistons were in spec! Simply a hone and some fresh rings. Got the rings on order and should hopefully see some parts back from boretech in the next week or two!

In the meantime, we finished off sanding, buffing and polishing the main covers for the engine:

Really happy with how they turned out!

We should have the cases prepped for paint shortly. Then we'll just have to wait for a warm day to paint. We'll get a warm day sometime in 2014 right?

 

[mayerjw2]

Lots to update on today! Things are moving along steadily, but maybe a bit little slower than we'd like... (lots of pictures to follow):

Got the head, jugs and cylinders back from bore-tech and they look great. Can't say enough about Bill and Bore-tech, great work, reasonable prices (considering the workmanship and experience), and an overall nice guy. We ended up with a hone on the cylinders, fresh rings on the de-carbonized pistons, new stainless steel intake valves, one new valve guide, valve seats cut and new seals to go with it. Plus we paid for Bore-tech to clean the parts as well:

Everything came back looking gorgeous I'd say... While those parts were at bore-tech we started in on cleaning the cases and prepping for paint. Here's what our upper crankcase looked like a few weeks ago:

So we gave the cases a good soaking to try and loosen up some of the caked on dirt and grime. This was followed by a lot of scrubbing by hand...

Getting the old gaskets off was as advertised (a real PITA)... Got to that point with all the cases and started taping them off for paint:

While Charlie watched...

We were finally ready to paint but Cincinnati weather wasn't cooperating in the slightest... Conveniently, Tony's family lives in West Palm Beach Florida and Tony had a trip scheduled to visit. Luckily for us, we picked up the bore-tech parts a few days before he was heading down so Tony took all the parts to sunny Florida for painting!

Here's his paintbooth in his parents garage:

First the self-etching primer:

Followed by the engine enamel (cast aluminum color):

And the finished product soaking up that Florida sun:

Tony did a heck of a job! Hard to believe its the same part as the one in the first picture.

Unfortunately though, he ran out of paint and couldn't find it anywhere down there. Apparently there are no O'Reilly auto parts stores in southern Florida! So the rest of the parts are coming back primed and once we get some warm weather will be getting the same treatment as that upper crankcase. In the meantime, the engine rebuild may begin with some frame sanding/stripping in between for good measure!

 

[huddy]

Wow great job on the paint. And I hear such good things about bore tech if you don't mind... How much did you pay for their work??

And what was your choice of cleaner for your parts soak?

Thanx

 

[Mydlyfkryzis]

It will be nice to have another CB360 on the road....

The stock front fender incorporates a fork brace in the mount....If you decide to go fenderless, at least replace the brace...The spindly 33mm forks are wobbly enough....Personally, I prefer fenders....I was out today (northern NJ) and the snow was melting and puddles everywhere...I had dirt from the road and salt and water in my face....

The motor is looking delicious....

 

[dtsmjr8dan]

Those cases are coming out great. I found out about that technique over fifty years ago and never forgot it.

 

[mayerjw2]

Wow great job on the paint. And I hear such good things about bore tech if you don't mind... How much did you pay for their work??

So we ended spending $285 on labor (clean/blast, decarbon/clean pistons, replace valve guide, fit piston rings, valve job, general assembly/disassembly). And another ~$170 on parts that I was able to buy through them (S.S. intake valves, the replacement valve guide, and complete engine rebuild gasket kit). Additionally, I sourced the new piston rings separately and supplied these to him to fit and verify. I would imagine a good chunk of labor cost could have been saved if we had chosen to simply have them measure the bores/pistons and then hone the cylinders and cut the valves. But for me, the assurance of knowing that the head and piston/rings/cylinders were rebuilt & measured properly under the experienced eye of Bill at Bore-tech will help me sleep at night and was well worth the money on my first engine rebuild. In the next engine I get into, I may try some of that myself.

And what was your choice of cleaner for your parts soak?

Good old-fashioned dawn dish soap and water! I figured if it's good enough to clean oil spills in the ocean, it oughta be good enough for the dirt and grime on the outside and the oil on the inside . One thing I would do differently though; take the engine studs off the upper crank case before soaking. The soapy water (and perhaps the length of time i let them soak) didn't play nice with the finish on the studs. Not that it matters, but thought I'd give you a heads up.

Mydlyfkryzis - that initial concept was missing quite a bit and we are planning to put a front fender on the bike. In fact, the bike is essentially going to be stock with a few upgrades (the new intake valves, roller bearings, bronze bushings, some electrical upgrades maybe, custom paint job, maybe some goofy white wall tires...). As you can see we've already opted to go with a more stock looking motor, painting it the gray vs. the semi-gloss black we originally thought we would. Excited to keep moving forward and one day get in on some of that delicious sounding road dirt, salt and water

Thanks for the compliments all!

 

[mayerjw2]

Warm weather has finally arrived in Cincinnati, just in time for opening day - Go Redlegs! It has also let Tony and I get some work done; we've been in a bit of a holding pattern on painting the parts. Finally turning the corner and starting the motor reassembly.

About 2 months ago, I took a new job which has really turned out to have been a great decision so far. I've been privilege to some unexpected friendships with coworkers who happened to have a history with motorcycles! One such new friend is Tom Aultz. To my surprise, I learned that Tom actually raced a Honda CB350 for years! Here's a few pictures Tom lent me of him in his younger days racing his 350 in the mid 70's:

These photos are awesome! They were taken at the Nelson Ledges racetrack. Look familiar to anyone? Tom currently rides a early 70's Moto Guzzi and has a late 60's Velocette waiting in the wings for restoration. He bought them both new!

The timing couldn't have been more perfect as Tom graciously offered up his machine shop (in his basement!) and his experience to help Tony and I with the bottom end reassembly (admittedly the single most intimidating part of a motor rebuild to a first timer).

We started with inspecting the crank and measuring runout:

She looks gorgeous and didn't require anything. Bearings are tight and well within spec. Regardless it was a great exercise that I wanted to go through to gain some experience/

Then began reassembly of the transmission:

It came together beautifully and proved to be fairly straightforward:

Tom hasn't aged a bit!

The trans looks great. Shifts smoothly through each gear and really shows no wear at all. Very thankful to Tom for walking us through it. Next time around Tony and I should be able to tackle it ourselves but boy was it nice having experienced eyes and hands guiding us this time. Doubt it will be the last time we look to tap into to Tom's wealth of knowledge!

Tony and I got our paint booth set up again and got the bottom crankcase finished:

Tony's talent is really on display here and I can't wait to see his work with the tank and side covers once we get there.

A little before and after action:

Beautiful.

There's something about the transformation that's beautiful in its own right; the before and after, the grime washed away and made new, the reclamation of the discarded. Lots of great life and spiritual parallels there!

Tony and I are planning to reassemble the bottom crankcase and button the two halves together tomorrow night. Big day ahead! Hopefully a reassembled motor update will be coming soon...

 

[mayerjw2]

More progress to update on! We keep chipping away at the motor, focusing all of our time on getting this chunk of the project behind us. After getting the transmission reassembled it didn't take much to get the rest of the top case components assembled:

We then set to work on assembling the bottom case. Though there really isn't much in there (oil separators, kick start mechanism, cam chain auto-tensioner bolt assembly), it still took us a couple of hours to go through it all.

Here's where things got interesting. With these beautiful cases ready for reassembly, the dirty old crank case bolts just looked horribly out of place and had to be addressed. That being said, we weren't interested in replacing them altogether. We had perfectly good bolts it hand that just needed some cosmetic attention. Though we're willing to spend when we need to, this seemed like a good place to get creative before pulling out the wallet.

I first soaked the bolts overnight in white vinegar. I was hoping this might be good enough, but unfortunately it took off the plating as well as the rust and grime. This worried me; particularly the fact that the bolts immediately began to surface rust. Having them plated was cost prohibitive and we didn't want to spend the time and money a complete electroplating home setup would cost. Painting them seemed like a bad idea considering we still had to torque them down. So after some brainstorming, my coworker Tom came up with the idea of soldering the bolt heads to essentially "silver plate" just the bolt head. Brilliant, and certainly worth a try!

This proved to actually be pretty challenging:

But we took a night and cranked em out:

We were hoping for the cosmetic "illusion" of a new bolt. But the main goal was that the bolt heads didn't draw the eye. In that case they'd most likely go unnoticed. I think it worked!

That being said, it was a pretty tedious process. We're happy we did it, but we may think twice before going the route again...

Finally we were ready to bolt the cases together. Took our time to prep the surfaces and lay down an even coat of hondabond. Then it was simply a matter of torquing the bolts down evenly and to spec! This happened last night and marked a big milestone for us and a personal accomplishment for myself

A discerning eye might notice a couple of things: First, the neutral retaining screw and lock washer on the top case (the ugly rusty parts...) were only put in place to assist in assembling the trans. They will be cleaned up to match. Second, and perhaps more concerning is that the clips for the electric starter motor (which should be mounted under two of the bottom crankcase bolts) are MIA. Oops... We had them cleaned off and ready to go yet we still forgot to install them. So two of those bolts will be coming back out (one at a time of course). If that's the worst mistake we make I'll take it.

All downhill from here, yeah?

 

[svcta]

Your build looks great! Can I ask what you're using to paint your case covers? I have polished mine as a way to keep busy while troubleshooting other problems and I need to paint them now.

 

[74cb360t]

looking good! Keep slaying away!