Author Topic: CB360 twin in Colorado (Read 6552 times)

brett_bike · « **on:** June 23, 2010, 06:24:10 PM »

Well, part way through my CB550F build I picked up this little gem for $200. Not too pretty, but with fresh oil, new plugs and fresh gas she fired right up. She was pretty filthy from sitting under a tarp next to a cabin for 7 years. I plan on taking this down to the frame after I get her running solid and make it a stripped down cafe racer.

Thoughts and advice for the build are not only welcome, but encouraged.

But, first things first...One of the exhaust studs is broke off, I'm looking for help/direction in removing it before I go any further.

scottly · « **Reply #1 on:** June 23, 2010, 07:14:07 PM »

Is the exhaust stud broken off flush with the head, or is there some of it sticking out?

brett_bike · « **Reply #2 on:** June 23, 2010, 09:39:53 PM »

Unfortunately it's flush with the head.

scottly · « **Reply #3 on:** June 23, 2010, 10:09:17 PM »

Bummer

You'll have to drill it out. You may wish to fashion a drill block that bolts on with the existing stud, to keep the bit centered. Use a left-handed bit (sometimes you get lucky, and the left-handed bit spins the piece out), and soak the broken stud liberally with something like PB Blaster and let it soak in as long as you can before you start drilling. A little heat may help. Worst case is you have to use a helicoil, or tap for the next larger bolt size. Good luck.

Gordon · « **Reply #4 on:** June 24, 2010, 12:59:39 AM »

Start keeping an eye out now for cheap used sets of carbs with good diaphragms. New diaphragms are hard to come by and very expensive when you do. Good tires aren't so easy to find in those sizes. As long as you don't have a problem with Cheng Shin, then you're fine.

What year is it? Mine's a '76 so I didn't have to mess with this, but the earlier models had cam chain tensioner problems. I don't know any specifics about that, unfortunately.

crazypj · « **Reply #5 on:** June 24, 2010, 09:24:11 AM »

If you have a welder you could try building up inside a nut (clamp nut centered over broken stud and just fill it up)
As it cools down spray with release oil.
Wait until it's fully cooled before trying to unscrew.
Sometimes it works and you don't loose too much time if it doesnt

PJ

brett_bike · « **Reply #6 on:** June 25, 2010, 10:14:31 AM »

Thanks for the heads up fellas. I need to search my local salvage yard for one new diaphram already, mine has a small tear in it. Could that be why my rpm's raise and lower when it idles?

Today I'll be installing new throttle cables and points/condensers, looking forward to seeing what that changes.

Gordon · « **Reply #7 on:** June 25, 2010, 11:05:54 AM »

Quote from: brett_bike on June 25, 2010, 10:14:31 AM

I need to search my local salvage yard for one new diaphram already, mine has a small tear in it. Could that be why my rpm's raise and lower when it idles?

Yep. It'll never run right with a torn diaphragm.

cb650 · « **Reply #8 on:** June 25, 2010, 03:21:00 PM »

If its a small tear you can use skotch coat electrical and it will be ok.

brett_bike · « **Reply #9 on:** June 25, 2010, 06:42:51 PM »

Is that the "liquid electrical tape" stuff?

cb650 · « **Reply #10 on:** June 25, 2010, 07:51:26 PM »

Yes Used it on mine last year. Havent tore them back apart to check but still running.

brett_bike · « **Reply #11 on:** August 11, 2010, 06:33:41 PM »

I just picked up a new vacuum diaphragm from a dude on ebay. When that arrives I'll get busy on the rebuild. Stoked, this bike should be fun.

cb650 · « **Reply #12 on:** August 12, 2010, 05:13:13 AM »

I enjoy mine. Ride it almost as much as the 650.

brett_bike · « **Reply #13 on:** August 23, 2010, 01:06:53 PM »

WEll, This morning I rebuilt the carbs, slapped it all back together and tried to sync everything. She is having a hard time idling smoothly, and wont calm down from high idle. Also, she spudders while on the road, and wont climb above 5000 rpm's.

Guess I will have to start from the beginning.

Any advice?

cb650 · « **Reply #14 on:** August 23, 2010, 01:57:58 PM »

Did you get the new points in? How about the air filters?

brett_bike · « **Reply #15 on:** August 23, 2010, 03:38:22 PM »

New points are in. Air filters are individual Uni foam filters. Currently running through the service manual and re-doing the carb adjustments and re-checking the cam chain, etc.

I noticed something strange when I was adjusting the carbs, then I twist the throttle and let it go, it doesn't roll all the way back to the start point. I need to give it a little push to get it closed - maybe that's normal, maybe not. I don't know. I do know that my CB500 and CB550f do not need the little extra push to get back to closed.

cb650 · « **Reply #16 on:** August 23, 2010, 04:30:39 PM »

With the carbs off?

brett_bike · « **Reply #17 on:** August 23, 2010, 05:38:00 PM »

Nope, carbs are on when this happens.

cb650 · « **Reply #18 on:** August 24, 2010, 05:39:12 AM »

Cables might be binding or need replaced.

brett_bike · « **Reply #19 on:** August 24, 2010, 07:04:42 AM »

Throttle cables are new, I'll check the routing to make sure there in no binding.

This morning I noticed that the left pipe took noticeably longer to get hot. I'll be checking the coils, wires and plug boots next.

brett_bike · « **Reply #20 on:** August 24, 2010, 03:28:44 PM »

update - I trimmed back the plug wires, now both pipes are equally hat to the touch. However, on the road she spudders with throttle above 5000 rpm's. If it's not one thing it's another.

cb650 · « **Reply #21 on:** August 24, 2010, 03:53:27 PM »

vacum leak? Did you oil the foam? mine dont like oiled filters. I have emgos and a mostly open exhaust. Runns good to 7k and thats as much as I push it. We 360 owners should get together. I know of 3 local and they are all blue.

brett_bike · « **Reply #22 on:** August 24, 2010, 05:22:06 PM »

mine is rattle can. Does thet count? I need to figure this bs out before i freat out.

cb650 · « **Reply #23 on:** August 24, 2010, 06:16:08 PM »

NP only running problem I have had with mine is when i bent the points plate and it wouldnt rotate enough to time it. And the torn diaphram that i used scotch coat on.
Although it dont like the stock pipes either.

brett_bike · « **Reply #24 on:** August 24, 2010, 06:52:49 PM »

Where are you located in Denver? I would love to come check out your sscoot to compare it to mine. Maybe I'll see something I\m missing.

Shoot me a PM and maybe we can meet up later this week if it's cool with you.

News:

Author Topic: CB360 twin in Colorado (Read 6552 times)