collapse

www.dimecitycycles.com


www.restocycle.com

www.CITYLIMITMOTO.com

www.jadusmotorcycleparts.com

www.bisonmotorsports.com

www.speedmotoco.com

www.cognitomoto.com

www.townmoto.com

www.sparckmoto.com

www.Moto-Madness.com

www.pistonsociety.com

www.steeltowngarage.com

GET DTT UPDATES ON FACEBOOK AND TWITTER

Author Topic: 1974 CB360 Engine Troubles (I think)  (Read 9658 times)

Offline rsjudka

  • Posts: 91
1974 CB360 Engine Troubles (I think)
« on: May 13, 2017, 02:20:07 »
Hey everyone!
I'm not exactly sure how to start, this is my first time posting but I've already read a ton of the posts on here!

I recently purchased a 1974 CB360 for some mechanic (or so he claimed🙄) and for the first 25ish miles it ran without any problems.

Now, I'm having an issue where white/blue smoke is coming out of the right exhaust as well as some oil. It is also occasionally popping while revving the bike.

I think the bike also is only running on one cylinder (when I unplug the left spark boot the bike dies, but runs the same when I unplug the right spark boot). I tested both coils and they seem to be working properly.

Finally, there is also a weird ticking noise that sounds like it's coming from the top of the engine.

I've done some basic maintanance to it (changed throttle cable, changed oil, replaced a cracked top triple tree) but haven't messed with the engine much.

I feel like these issues could all be related, but I'm extremely new to motorcycles so I'm not sure.

Could someone point me in the right direction to get started? Also, if you think this is more serious of an issue, should I just take the bike to a shop? I would rather much work on it myself.

EDIT: Also forgot to mention, when I ride the bike, for the first 5 minutes or so it feels as if the bike is half powered, can't get over 30 mph. Bike has a very deep growl noise. Then, all of the sudden, the bike rides fine, great power. Sounds like it should (aside from the ticking).

Cheers,
Robert
« Last Edit: May 13, 2017, 02:26:59 by rsjudka »

Offline trek97

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 5178
Re: 1974 CB360 Engine Troubles (I think)
« Reply #1 on: May 13, 2017, 07:41:07 »
Could someone point me in the right direction to get started?


Start here...
http://www.dotheton.com/downloads/CB360T.pdf

Check for proper oil level, Cam chain adjustment (engine at operating temperature), Valve adjustment (engine cold), Points gap / Timing check and adjustment (Stroboscopic timing light - engine at operating temp), Carb sync check and adj - Air/fuel mix adjustment (on center stand, engine at operating temp). 

In that order.  :)

« Last Edit: May 13, 2017, 08:03:09 by trek97 »

Offline redwillissuperman

  • Posts: 997
  • Keep it simple- engine, wheels, bars
Re: 1974 CB360 Engine Troubles (I think)
« Reply #2 on: May 13, 2017, 11:29:32 »
Hey everyone!
I'm not exactly sure how to start, this is my first time posting but I've already read a ton of the posts on here!

I recently purchased a 1974 CB360 for some mechanic (or so he claimed) and for the first 25ish miles it ran without any problems.

Now, I'm having an issue where white/blue smoke is coming out of the right exhaust as well as some oil. It is also occasionally popping while revving the bike.

I think the bike also is only running on one cylinder (when I unplug the left spark boot the bike dies, but runs the same when I unplug the right spark boot). I tested both coils and they seem to be working properly.

Finally, there is also a weird ticking noise that sounds like it's coming from the top of the engine.

I've done some basic maintanance to it (changed throttle cable, changed oil, replaced a cracked top triple tree) but haven't messed with the engine much.

I feel like these issues could all be related, but I'm extremely new to motorcycles so I'm not sure.

Could someone point me in the right direction to get started? Also, if you think this is more serious of an issue, should I just take the bike to a shop? I would rather much work on it myself.

EDIT: Also forgot to mention, when I ride the bike, for the first 5 minutes or so it feels as if the bike is half powered, can't get over 30 mph. Bike has a very deep growl noise. Then, all of the sudden, the bike rides fine, great power. Sounds like it should (aside from the ticking).

Cheers,
Robert

Engine is f*cked most likely but small possibility it's electrical. The spark plug "boot" is a separate slip-on piece. There is a brass spike in the boot that pierces into the center of the spark plug wire. Pull the boot off, cut off 1/2-inch of plug wire, and reinstall.

On the engine stuff- put on a pair of Mechanix gloves. Start bike. Immediately touch headers a few inches from head. Both should be getting warm. Go for 5minute ride.  Check headers. Both should be HOT. Most likely right will be dead cold. Try above spark plug fix. Re-test.


Offline advCo

  • DTT BOTM WINNER
  • *
  • Posts: 2201
  • Nick Ol' Eye
    • adventur Studios
1974 CB360 Engine Troubles (I think)
« Reply #3 on: May 13, 2017, 13:24:48 »
Agreed with both of the last 2 posts. The carbs on the 360 can be very finicky especially if the intake or exhaust has been modified (pods, open exhaust), and the slightest bit off sync can cause running on one cylinder.

It's good practice to do as red said and make sure you're getting a good bite on the spark plug wires.

I would start there, making sure you have spark on both sides: pull plugs out and turn the engine over with the spark plug in the holder and the threaded part touching the engine - you should see a nice blue spark on each side. If not, test your coil on the suspect side.

Once you can confirm spark, 100% go through and do the manual maintenance procedure trek recommended. Follow it to a T. If you are worried about it at all, there is a great set of videos on YouTube by Common Motor Collective that go through all of the procedures in the manual step by step for the Honda twins. They were very helpful for me my first time around.

The ticking is most likely loose valve tappers and will be adjusted in the maintenance procedure. The bike 'warming up and running fine' sounds like carb sync to me.


Sent from my iPhone using DO THE TON
« Last Edit: May 13, 2017, 13:26:29 by advCo »
"He broke the mirrors off his Cadillac, 'cause he doesn't like it looking like he looks back."

74 CB360 - Luna - http://www.dotheton.com/forum/index.php?topic=63294.0
82 GS550L - Tracker-ish - http://www.dotheton.com/forum/index.php?topic=67229.0 - Sold
74 XL350 - The Turd - http://www.dotheton.com/forum/index.php?topic=70252.0
Suzuki FA50 "No-Ped" - http://www.dotheton.com/forum/index.php?topic=71189.0
73 Suzuki RV125 -http://www.dotheton.com/forum/index.php?topic=73875.0

Offline irk miller

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 6717
  • You've been mostly-dead all day.
Re: 1974 CB360 Engine Troubles (I think)
« Reply #4 on: May 13, 2017, 15:00:32 »


EDIT: Also forgot to mention, when I ride the bike, for the first 5 minutes or so it feels as if the bike is half powered, can't get over 30 mph. Bike has a very deep growl noise. Then, all of the sudden, the bike rides fine, great power. Sounds like it should (aside from the ticking).


This sounds like the points shorting out.  Do you have the gasket under the points cover?  I paint the inside of my points covers with the liquid tape.

Offline rsjudka

  • Posts: 91
Re: 1974 CB360 Engine Troubles (I think)
« Reply #5 on: May 13, 2017, 16:08:13 »
Engine is f*cked most likely but small possibility it's electrical. The spark plug "boot" is a separate slip-on piece. There is a brass spike in the boot that pierces into the center of the spark plug wire. Pull the boot off, cut off 1/2-inch of plug wire, and reinstall.
So if its not an electrical problem, is it not possible to fix the engine? Or would it just require some extra work?

On the engine stuff- put on a pair of Mechanix gloves. Start bike. Immediately touch headers a few inches from head. Both should be getting warm. Go for 5minute ride.  Check headers. Both should be HOT. Most likely right will be dead cold. Try above spark plug fix. Re-test.
I have checked the engine heat. On startup the left side warms up but the right side is cold. After a 5 minute ride, the left side is burning hot and the right side is only warm. Would it being warm be different than being dead cold?

Thanks for the tip on the spark plug fix, I will definitely try that out when I have the time!

Offline rsjudka

  • Posts: 91
Re: 1974 CB360 Engine Troubles (I think)
« Reply #6 on: May 13, 2017, 16:11:58 »
I would start there, making sure you have spark on both sides: pull plugs out and turn the engine over with the spark plug in the holder and the threaded part touching the engine - you should see a nice blue spark on each side. If not, test your coil on the suspect side.
I've tested for spark on both sides and I do see a blue spark. However, I'm not sure how big the spark should be.

I have also tested the coils just to see if that could be the issue, and they both spark (as for how big the spark is supposed to be, I'm not sure).

Offline rsjudka

  • Posts: 91
Re: 1974 CB360 Engine Troubles (I think)
« Reply #7 on: May 13, 2017, 16:14:32 »
This sounds like the points shorting out.  Do you have the gasket under the points cover?  I paint the inside of my points covers with the liquid tape.
I do have a gasket I plan on installing under the points cover. I have noticed some oil leaking through the points and am waiting for the seal and rubber plugs to come in some I can try to stop that leak.

Should I invest in some new points or first wait to stop the leaking, then see if the issue continues?

Also, if I need to replace the points, should I replace the coils too?

Offline trek97

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 5178
Re: 1974 CB360 Engine Troubles (I think)
« Reply #8 on: May 13, 2017, 16:35:10 »
Jesus!  Just do what I said to do.  then we can go from there.   ::)

Dont go blowing your money on parts you may not need.  Spend it on the tools you need to find which parts you need.

sync gauges...
http://www.ebay.com/itm/2FastMoto-2-Carburetor-Synchronizer-Carb-Vacuum-Gauge-Sync-Tool-Honda-/201802347691?hash=item2efc5b74ab:g:rYkAAOSwNnRYkQV6&vxp=mtr

Gauge adapters should be bought from crazypj right here on DTT (probably cheapest)
or...
http://www.common-motor.com/honda-360-carb-ports

timing light
https://www.harborfreight.com/timing-light-with-advance-40963.html
« Last Edit: May 13, 2017, 16:50:13 by trek97 »

Offline irk miller

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 6717
  • You've been mostly-dead all day.
Re: 1974 CB360 Engine Troubles (I think)
« Reply #9 on: May 13, 2017, 17:42:53 »
Here we go, let the attitude begin.  Good luck, my man.  I hope you get it sorted.  Maybe when we're allowed to, we'll talk about how to diagnose certain symptoms.  But for now, listen to mom.