[Steveolio]

So it's been a while since I've been on the forums.

Last summer I was riding to work on my 1974 CB360 and she just starting spitting and sputtering, I think one of the cylinders stopped firing, and then she died all the way. I tried kicking her over for about five minutes and no success. So I started walking her home, I was only a mile from the house, but I live in Seattle so of course it was up hill. There was a lot of pissing and moaning on my part. After about five minutes of walking I give her a few more kicks and she sputters to life but ONLY after I hold half throttle. This works for about 2 blocks, but thank god, I'm now up the biggest hill. I walk her the rest of the way home, park her in the corner of the garage, call her dirty names, and neglect her for about 7 months.

So I don't hate her anymore, but I certainly didn't treat her right. Where do I start, is there a list of things I should check to root out the problem and get her back in riding condition? The bike has about 16k miles on it, has always had trouble running consistently for the 5 years I've owned her. I had it running great for about 12 months after 66Sprint helped me out. So I think I know how to recheck everything, but I'm wondering if its finally time to rebuild the whole engine? Will this ensure the bike runs more consistently? Do I need to have a more through maintenance schedule? Should I change from points to electronic ignition?
I would like to have a daily rider bike so I'm honestly contemplating getting her up and running and selling her for a fuel injected bike. I don't want to do this but I also know now from my years of owning the bike that it's about 50% riding 50% fixing the bike and I would like it to be more like 90% riding 10% fixing. Is that ever achievable with a 1974 CB360 bike?

Thanks for your thoughts fiends,
Steve

 

[spirograph]

Fuel/air mix, compression, and spark - it's gotta be one of those three things. I'd start with a regular tune-up; clean out the slinger and the mesh screen, new oil, cam chain tension, timing and tappet clearance.

Then I'd:
-Verify spark (inline spark tester or the screwdriver trick) - also, make sure the inside of your points cover isn't contacting the wires and shorting your points
-If that doesn't fix it, verify compression with a compression tester
-If compression is good, probably time for a carb rebuild

I'm in Seattle as well, so if you want an extra set of eyes on the bike, feel free to PM me. In general, I wouldn't recommend an engine rebuild unless you have a compression problem - if you're anything like me, you'll be equally liable to make it worse as make it better long run, how often do you do your routine maintenance? The 1500 mile tune-up, or do you go longer? You still have to do that with e-ignition, it just makes it a little shorter because you can skip timing.

 

[spirograph]

Another thought - what's your battery situation? Old, new, lives on a trickle charger, new reg/rec?

 

[J-T]

When something suddenly quits like that it's usually something really easy to fix. It's just not necessarily easy to find.

If you really want to know what happened you need to check/fix one thing then see if that fixed it. If not, try one more thing.

Kick it over slowly and listen for strange/unusual noises.

I'd start by verifying spark. Try it with the plugs that are there now first.

While you have the plugs out anyway, just as well check the compression. It won't be up to spec (cold) but will at least tell you you have some.

If either plug looks really black/sooty go to the carbs. Symptoms like yours can happen when a float valve sticks open.

 

[Steveolio]

spirograph: clean out the slinger and the mesh screen

What's the slinger? Is the mesh screen you are referring to in the oil filter or the petcock?

spirograph: I'm in Seattle as well, so if you want an extra set of eyes on the bike, feel free to PM me.

Good to know, thank you for offering your help, I'll PM you if I start cursing at it again.

spirograph: Another thought - what's your battery situation?

It's at least 2 years old, lead-acid, and I charge it when the bike sits for a while. When the bike was up and running smooth I checked to make sure that the charge circuit on the bike was functioning properly, and it was at the time. Are you recommend I start with new plugs and new battery? Then do a normal tune up?

J-T: I'd start by verifying spark. Try it with the plugs that are there now first.

Last year I verified that the spark was working well, but because I've always done the points timing myself I've never felt confident that I've gotten it 100% right. Obviously I did a well enough job when it was running for 10 months but it always seemed to me that it was off at higher RPMs (3500). Maybe this was just my imagination playing on the fact that I don't feel confident in the tools/procedure I used. I did the timing when the engine was off (but warmed up).



So it looks like I should start with a tune up (oil change, spark plugs, timing check, cam chain tension, new fuel, check fuel lines, and maybe a new battery).

 

[spirograph]

For sure! The 360 is about the only thing I know a damn thing about

The slinger is the sort of round cup under the right side engine cover - the CB360 doesn't have an oil filter, and instead passes oil through that cup (spinning at high speed) to centrifuge out any particulate. It works reasonably well, but you have to remove a circlip and then pop the cap off of it to clear out the gunk every once in awhile. I'll see if I can find a picture for reference.

If you've got a multimeter, you can read the DC current across the battery poles; if it's less than 12.7v fully charged (I think, though someone will be along to correct me shortly if I'm off on my numbers), your battery is probably toast at this point. It's not uncommon for L/A batteries to die in two years depending on how they're cycled and treated (warm vs cold storage, etc.). Weak batteries will make these bikes run like crap, so that'd be a decent place to start.

If you're getting weird firing over 3500 rpm, it might be an issue with your advance - if it's sticking or the springs are loose, that could affect whether or not you're getting full spark advance. Have you tried checking your work with a timing light? (the gun kind while it's running, I mean).

 

[Rob Axel]

.. well it's not a 360 but (weather permitting) my wife rides her 450DOHC to work whenever she can. I am by no means a mechanic, I know enough to keep me in trouble and the bike needs work. If you are set on going fuel injected, go for it..BUT DONT SELL THE 350.. keep it and learn. Yeah, being able to just hop on, push the button and go has its place..BUT, the "cool factor" is off the charts with a vintage bike! Especially when you can learn with it and not rely on it as yoUr sole transport.
Plus, there is nothing worse then seeing someone else riding a old bike and getting that pit in the bottom of your stomach then thinking .."why did I let her go..."
Life is to short to drink bad beer and live with regret..

 

[76TWIN]

I would suggest doing these in this order

1. Check battery. If below 12.6V at full charge and resting then it's no good. Replace it if so. I would recommend using an AGM type battery instead as these are much more robust and reliable.
2. Check for compression. If no compression then you can stop here and know that you're in for a top end rebuild at the very least.
3. Check spark plugs. If fouled, clean them up or replace as needed. Take some pictures of them and post them for us to review.
4. Check spark plug wires and caps for breaks and cracks. Replace as needed.
5. Check cam chain tension and adjust as needed.
6. Check valve clearance and adjust.
7. Check cam timing.
8. Check ignition timing and adjust points.
9. Turn on the bike and check for sparks. If no spark, then check the ignition coils, plug wires, and condensers and replace as needed.
10. If you have sparks but the bike still won't start then spray a bit of starting fluid into each carb's intake and try starting again. If it starts then you have a fuel delivery issue. Time to take the carbs apart and clean them thoroughly.
11. If it will still not start even with the starting fluid then go back to step 3 and go through the whole ignition system again.

 

[jakec]

I'm in seattle, if you don't want it anymore, I'll take it... I hope it's orange ;-)

Anyways sounds like a fuel issue if you were able to get it going by starting it with half throttle. That would mean that the fuel / air mixture was off.

- OR -

It could be running on one cylinder (likely). Bike won't idle or start without throttle when this happens. And then when you ride it it'll be weak.

FIRST - check spark and set SET don't "check" SET the timing.

Does it have separate fuel lines for each carb? First thing is to check those to make sure both are getting fuel. Then check the carbs and see what your float bowls look like, and adjust them.

Yesterday I had a unique experience, I was flying down westlake coming around the big bend headed north near the aurora bridge, doing a tear-jerking 46 mph at WOT on my CL175. After about 30 seconds at WOT i starter loosing power and the bike began to slow down. Finally I came to the stop light at the Fremont bridge, and when it turned green the bike would barely go with my weight on it.

I'm on the bike thinking **** I really just blew the head gasket by maintaining 6k rpm for too long? What really happened was I was almost out of gas (already on reserve) and I was using fuel faster than it could get to the bowls.

I have also had early mornings where the bike wouldn't start right, all I had to do was prime (squeeze) one of the fuel lines until I saw the inline filter fill up and that cylinder started running. Another thing is All my carb'd bikes have had a tendency to want to cut out if i'm coasting downhill with no throttle input. Something about how the fuel flows. Maybe this happened to you.

 

[spirograph]

Losing power on Aurora is my nightmare - those lanes are like three feet wide to start, and it somehow feels uphill in both directions

+1 on the running on one cylinder. Among the myriad suggestions here, try running it with the points cover off - if it runs, you’ll know one of the points is shifting to the cover.

Edit: Ohhh, Westlake. That’d be less panic inducing for me once I had a similar one-cylinder-firing issue at the bottom of the massive hill by the Montlake Bridge. The fun part was pushing it all the way up 23rd to where I live, at the top of the hill...

 

[jakec]

Last month I pushed my dad's bike about 3 miles on the burke gilman after it shredded it's advance plate. that was flat though

Post some pictures of this 360!

 

[spirograph]

The funny looks from all of the bicyclists was just overwhelming jealousy, I promise

I dunno we mean mine or his, but because I'm shameless, feel free to flag me down if you see this on the road!

 

[jakec]

Spiro, and other Seattle members in this thread:

sorry to hijack the thread but we're just waiting for the OP to come back so might as well...

Do any of you guys have a lead on a cheap titled twin? Doesn't have to be pretty, it can even be from the 80s. I have a friend that I am trying to help get into the sport, and he's tight on cash, as they usually are. I want to find him a small displacement bike, like a cm200 or something cheap and undesirable like that.

 

[spirograph]

I might have something - a buddy of mine’s got an ‘81 CM185T, but it’s been a little bratted out, so it might take a little work to get back to pretty. Not sure about the title status either. I’ll ask him, but don’t feel obligated, it’s not a perfect project. I monitor craigslist pretty religiously, and I’m maxed on bikes, so if anything good crops up I’ll send it your way. Only thing on there right now is a pretty crusty 360 down in Tacoma - (https://seattle.craigslist.org/tac/mcy/d/1974-honda-cb360/6515218889.html). If you can get him down to $200-300, could be worthwhile, but it’s a lot of wirewheeling

 

[76TWIN]

This one is cheap and is titled

https://seattle.craigslist.org/tac/mcy/d/1974-honda-cb360/6515218889.html

it's a bit rough though.

 

[jakec]

Oh, I've seen the rust bucket in tacoma. I was thinking more along the lines of throw a battery in it and rebuild the carbs and let him ride :-D

 

[76TWIN]

Oh, I've seen the rust bucket in tacoma. I was thinking more along the lines of throw a battery in it and rebuild the carbs and let him ride :-D

Not gonna happen for cheap I'm afraid. Especially as the weather is getting warmer, prices will start to go up.

 

[jakec]

It can happen! Like I said, it can even be ugly... or worse, from the 80s.

Here's a good candidate that I am just waiting for a reply on, to see if he has a title.

https://offerup.com/item/detail/307939758/

 

[76TWIN]

" It is not currently running and has exhaust pipes set aside..." Not running is a far cry from "throw a battery in it and rebuild the carbs and let him ride"

 

[spirograph]

It could be, though. The guy who posted it needs time to figure out how to put the exhausts back on so not running might be a matter of turning on the petcock...