74 CB360 cranks, backfires, but won't run

dlogreen

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Hey guys! I’ve got a thread open currently for my CB 360 build, but that’s more for pictures and progress.

I’ve got it all back together after being in several pieces while rebuilding the top end and building a custom harness.

I’ve done custom harnesses before, so I don’t think the electrical is the issue, because everything on the bike works, and I have confirmed the spark and starter function.

I built a custom two and into one exhaust that merges from 1.375” headers to 1.75” just as the exhaust reaches the bottom of the frame and then redirects under the belly. When I first put it back together, I had the carbs set around 23 mm, because that’s where they ran before I took it apart. I’ve cleaned the carbs numerous times, and then last night set them to 20 mm. I believe there is a chance the aftermarket float needles that came in the rebuild kit could be hanging up, because I have a random overflow from time to time, but then it will go away because I know that float height isn’t too ridiculous.

I have experimented with the choke and mixture screws from half a turn out to 3 1/2 turns out and the best I can get is some backfiring out of the carbs, but nothing that resembles wanting to actually run on its own.

I’m running pod filters with an extension sleeve to help smooth out the air intake, which is exactly how they were when it ran before even though it had a leaky top end. The secondary jet is 112, the primary is a 68 and the pilot is a 35.

Is it possible that there’s just not enough back pressure from my exhaust, even with an adjustable baffle set to the next last hole, and therefore too much air is flowing?

I’ve only ever had carved bikes, and never had any trouble with valves points or carburetors, so I’m a little bit lost right now. I would appreciate any input.

I plan on tearing them back apart tonight or tomorrow and checking the pilot for any sort of blockage again or seeing if any of my air passages may have gotten clogged while the carbs sat waiting for the frame to be finished.

Also, if anybody has attempted to run their bike with straight pipes, what sort of settings did you use? I have a feeling this bike is going to behave as if it is a straight pipe, even though I have a baffle in line and will eventually get a cone muffler on there. But as far as I know, open headers can still run well enough to get the bike to start so what could I be missing?
 
Have you removed the advancer from the camshaft for any reason? If so, did the points cam come off it in the process? If true, you might have put the points cam on backwards, it's easy to do.
 
Every single time I’ve had this happen to me it’s timing 180 out. Either through flipping the leads to the coils, timing on wrong stroke or as suggested above, the advancer installed 180 out.
 
It sounds like the timing may be off. Roll the engine over until the left points are just opening( firing position). Is the "F" mark,on the rotor, lined up with the pointer? Are both valve rockers loose(both valves closed) ?
 
I don't think the carbs are the issue, either, but I wonder about the initial 23mm and later 20mm float height settings. I believe the stock setting is 18.5mm, so your higher values would be more lean, yet you believe your exhaust will operate like straight pipes, which also tend to lean out the mixture. I guess you have a larger secondary, but I wouldn't change from the stock float height until a later point in the tuning, if at all.

I would also think about whether it will be better for you in the long run to collect relevant posts in the project thread. It's nice to have a chronological record of things without having to cross reference a bunch of separate threads.
 
Thanks a ton so far.

So after new rings and cleaned pistons, head, valve cover, and gaskets, I triple checked the timing when I first put the camshaft back in…

And with everything buttoned back up, I’ve also checked the valve lash, pointed gaps, static timing with a light and multimeter, and I mean it’s as exact as I feel I can get it using my naked eye.

That said, obviously the advancer was removed and it sat while I chopped the frame and built the new harness and hump seat. I did notice it has a different lobe on either end so maybe that’s where I’ll check tomorrow before tearing the carbs out again.

Would I just pull off the advancer and flip over the cam?

Also compression is pretty good and wants to turn itself over on the compression stroke when manually rotating, so that part I’m fairly certain of.

If the timing was 180 out, would flipping the points bullet ends correct that? As far as I know the coils only fire as a result of the points breaking so left or right only matters for orientation based on which opens when…

For the carbs, I felt something was goofy cuz at one point I tried to restrict the intake and then I got gas dribbling out the exhaust…. But that could have just been cuz it wasn’t igniting and being expelled thru the exhaust valve🤷🏾‍♂️

I think that's everything.... I'll check the advance cam in the am and then retry before I pull anything else apart.

Oh, float height.... I have some Vinton rings that might a little more proud of the groove than stock, so 0.5mm puts me closer to that 18.5 recommended... Though i do think the float needles are getting hung up. I'll address that after the cam if it's not behaving better.

I appreciate you guys. I will say old sohc twins are a breeze compared to dohc or even sohc 4s😅.

Here's a pic so you can see how she sits currently.... I'll be updating the build thread this weekend I hope. IMG_3759.jpegIMG_3761.jpegIMG_3760.jpeg
 
dlogreen said:
If the timing was 180 out, would flipping the points bullet ends correct that? As far as I know the coils only fire as a result of the points breaking so left or right only matters for orientation based on which opens when…
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No. The points will not be opening at the right time relative to the compression stroke for each cylinder.

This is the difference between 180° cranks that need two sets of points and 360° cranks that employ a single set of points and a wasted spark setup.
 
Here is a pretty good video that talks about 350 and 450 spark advancer cam alignment and I assume the 360 would be the same. If not someone with CB360 experience please advise.

 
I'll include a quick sketch to show how the pistons and points are timed. Flipping the advance shifts the points graph by 360° on the crank, which will not flip the locations of left/right cylinders firing. It just puts the cylinders on the exhaust stroke rather than the compression stroke.

713.jpg

The points curves are admittedly simplified here, but convey the timing information.
 
stl360+450 said:
I'll include a quick sketch to show how the pistons and points are timed. Flipping the advance shifts the points graph by 360° on the crank, which will not flip the locations of left/right cylinders firing. It just puts the cylinders on the exhaust stroke rather than the compression stroke.

View attachment 56056

The points curves are admittedly simplified here, but convey the timing information.
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Dude that's a great visual. I did not realize that's how they were timed but it makes sense bc they are 4 stroke 180 right? Either way I see how flipping the points would lead to this, and earlier I actually witnessed the crank want to stop itself bc the ignition happened on the exhaust and it fought the starter trying to turn it. I quickly flipped it back.

So the advancer cam really makes this much difference? That's nuts. I'll be up like 8 eastern time to flip it... Guessing I'll need to retime or at least readjust my points yah?

This has been great learning tonight. Thank you guys
 
It might help to go through the static ignition timing while thinking about the compression and exhaust strokes. You should be able to determine unequivocally whether the advancer cam is correctly oriented or not. I think this is better than flipping it because something seems to be wrong.

For example, the left valves are adjusted on TDC for the compression stroke with both valves closed. You know you're on the compression stroke if both tappets are loose. This should be right after the left points open.
 
stl360+450 said:
It might help to go through the static ignition timing while thinking about the compression and exhaust strokes. You should be able to determine unequivocally whether the advancer cam is correctly oriented or not. I think this is better than flipping it because something seems to be wrong.

For example, the left valves are adjusted on TDC for the compression stroke with both valves closed. You know you're on the compression stroke if both tappets are loose. This should be right after the left points open.
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Yah that's why I feel like I have that right. I set the points on the bike when got it in January and had it running ok but the right cylinder had a gouge and was spewing oil. So I set it the same way but that was obv before disassembling the top end...

Again I'll double check in the am.
 
I bought a really nice CB360 once, for a very low price, because the seller could not get it to start. Took it home, took the points cam off the end of the camshaft, rotated it 180 degrees (1/2 a turn), screwed it back in place, started it and it ran very well. Took about 15 minutes.
 
I think I'm gonna cry guys.... Y'all were right about the advance cam lobe. I flipped it and then in my haste and used am impact to tighten the bolt because I used it to break it free.... Not thinking. I broke the F***ING end off the camshaft. I want to throw up right now.

Obv I gotta replace it now. Anybody have a spare to sell or should I just ebay?IMG_3773.jpegimage.jpgimage.jpg
 
dlogreen said:
I think I'm gonna cry guys.... Y'all were right about the advance cam lobe. I flipped it and then in my haste and used am impact to tighten the bolt because I used it to break it free.... Not thinking. I broke the F***ING end off the camshaft. I want to throw up right now.

Obv I gotta replace it now. Anybody have a spare to sell or should I just ebay?
Click to expand...
PICTURES. There might be something that can be done, but we have to see it to know....
 
ancientdad said:
PICTURES. There might be something that can be done, but we have to see it to know....
Click to expand...
Can you see the second photo above? image.jpgThe extension is totally off but protruding....I looks like I could potentially tap and thread it if I can get a perfect hole. I know there's not a lot of tension on this part
 
dlogreen said:
Can you see the second photo above? View attachment 56076The extension is totally off but protruding....I looks like I could potentially tap and thread it if I can get a perfect hole. I know there's not a lot of tension on this part
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I'm gonna try to tap it. I was already making M6 tapped holes for other attachments and my electronics tray before. I'm gonna remove the bolt, hold the broken piece in place and then get a reference point..... Drill it and tap the cam shaft end for a longer bolt. Looks like a 16mm so if I can get another 6-8mm of thread it'll def hold enough for the job it has to do. I ordered a shaft on eBay already just in case cuz it had free returns
 
dlogreen said:
I'm gonna try to tap it. I was already making M6 tapped holes for other attachments and my electronics tray before. I'm gonna remove the bolt, hold the broken piece in place and then get a reference point..... Drill it and tap the cam shaft end for a longer bolt. Looks like a 16mm so if I can get another 6-8mm of thread it'll def hold enough for the job it has to do. I ordered a shaft on eBay already just in case cuz it had free returns
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Just realized the tip of the shaft is about 30mm long..... And not drilled through.... So I got the shaft drilled and now gonna clamp and drill my broken off tip through. I'll retap it if necessary... But I just need it centered to mate with the other end. Luckily it was uneven so the ends can only go one way and if I'm careful I can get it seated again with a longer bolt and maybe a little epoxy to keep it in place while it sets
 
That is unfortunate — sorry that happened.

That said, I wouldn't run it like that. The CB360 top end can be serviced in the frame, so it's not as hard as it might otherwise be to remedy.

I would look on eBay or call around to motorcycle scrapyards to find a replacement camshaft. They come up on eBay frequently.
 
And now we wait...😅... Either an hour or 4 days. The drilling and tapping went well and I had some 35mm M6 on hand so it's now secured and curing. Really only need there to be reference marks for when I put the advancer back on and let the little nib engage. It can't be more than a few micrometers from perfect thanks to the uneven shearing... Which can be accounted for with shifting the plate.

I took my time and understand this is likely a temp fix but could hold on. Worst case will be I have an extra camshaft on hand later.... Or I could bevel the edges and then run a bead of weld bc this stuff is ferrous. I cleaned all the shavings up with a neodymium magnet so surfaces were clean and then hit with parts cleaner and isopropyl alcohol to prep for the Tank Bond. I've used it before to temporarily mate engine surfaces before a weld or other mechanically sound fix could be applied.

Fingers crossed. I just need to hear it run and then I can tear the valve cover off and replace it with a new shaft. Luckily I'm a part time musician who's gigs cover all my hobbies including other music gear and guitars. The shaft was $100 on eBay and I made that in tips alone last Wednesday🤗

Here's a few shots of the process...IMG_3776.jpegIMG_3777.jpegIMG_3778.jpegIMG_3780.jpeg
 
stl360+450 said:
That is unfortunate — sorry that happened.

That said, I wouldn't run it like that. The CB360 top end can be serviced in the frame, so it's not as hard as it might otherwise be to remedy.

I would look on eBay or call around to motorcycle scrapyards to find a replacement camshaft. They come up on eBay frequently.
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Agreed. And likely what I'll do. But for the time this is okay.

We used to have several motorcycle yards and I sourced cb550 and cb750 and fzr600 parts from it.... But they shut down.

I ebayd a new one, but it'll take a few days and I'll be out of town all weekend soooo next week would be my earliest opportunity and I still work and stuff.

The deed is done, so now I'll see if it works. It's FIRMLY ATTACHED...... And the amount of rotational forces on that part clearly aren't strong if a quick tap w an impact totally yanked it off lol

In every sense of the word I'm a DIYer which includes messing stuff up and coming up with fixes. Should have been an engineer, but I thought medicine was a better choice until I hated being in school that long. So I'll take shade tree mechanic and mad but thoughtful scientist and hobbyist as a close second.

Wish me luck! There will definitely be a video of the first start up after this bonehead fiasco
 
Vid 1

Vid 2


Yeah I'll definitely be replacing the cam shaft bc it's cast iron and doesn't like high torque which was semi necessary to get the thread lock to hold. I rode it some but noticed when it got really going it wanted to loosen.

I tightened it back a few times before thinking some all thread as a stud might work but it didn't hold as well as I wanted.

I've got a couple other ideas that involve a cross drilled hole for a set screw or tack weld. If it wasn't cast iron my fix would have held but I don't mind tearing into the top a little more later....

I found a few header pin hole leaks and an oil leak from the clutch cover so I'll also be addressing those next week and then fresh oil again.

The bike idled strong as hell but off idle sputtered a little unless I feathered the throttle so there's some tuning to do.... Needle is shimmed with one washer.... but that's usually more midrange right?? Float bowl level too low, so lower float height to 17-18?

I'll upload a few other vids the HOA super took after we chatted some.

The baffle helps some but I'll pack it and it'll do even more for the feel and tone. I'm also considering going up to 115 or 120 on mains. Can't hurt to have em anyhow cuz currently there are 112 inside. I saw 70 primaries available but I'll go that route after float height and more fiddling once the new camshaft gets here.
 
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dlogreen said:
Vid 1

Vid 2


Yeah I'll definitely be replacing the cam shaft bc it's cast iron and doesn't like high torque which was semi necessary to get the thread lock to hold. I rode it some but noticed when it got really going it wanted to loosen.

I tightened it back a few times before thinking some all thread as a stud might work but it didn't hold as well as I wanted.

I've got a couple other ideas that involve a cross drilled hole for a set screw or tack weld. If it wasn't cast iron my fix would have held but I don't mind tearing into the top a little more later....

I found a few header pin hole leaks and an oil leak from the clutch cover so I'll also be addressing those next week and then fresh oil again.

The bike idled strong as hell but off idle sputtered a little unless I feathered the throttle so there's some tuning to do.... Needle is shimmed with one washer.... but that's usually more midrange right?? Float bowl level too low, so lower float height to 17-18?

I'll upload a few other vids the HOA super took after we chatted some.

The baffle helps some but I'll pack it and it'll do even more for the feel and tone. I'm also considering going up to 115 or 120 on mains. Can't hurt to have em anyhow cuz currently there are 112 inside. I saw 70 primaries available but I'll go that route after float height and more fiddling once the new camshaft gets here.
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What's really important is that it starts and runs. Before this adventure it wasn't starting, so now you know it's basically strong and, with a proper cam and some tuning it'll be good enough to get you in trouble!
 
That's a win. And it was nice seeing that satisfied grin when it fired up and held idle on its own. Nice work.

The tank paint looks pretty good. I'm not a fan of the original tank decals for the 360, so a nice solid color seems like an upgrade to me when the bike has other modifications.

I guess the inertia of the bolted on cam section is the issue for long term use. When you give it a blip it will effectively tighten the bolt for you, but when the cam slows down upon throttle release, the end of the cam wants to keep spinning fast and this will act to unwind that bolt. As you mentioned a tack weld might help, but that could introduce an imbalance. Slow winding down of the rpm would help, too, but not as much as that replacement cam you ordered. Did you order a top end gasket kit, too?
 
stl360+450 said:
That's a win. And it was nice seeing that satisfied grin when it fired up and held idle on its own. Nice work.

The tank paint looks pretty good. I'm not a fan of the original tank decals for the 360, so a nice solid color seems like an upgrade to me when the bike has other modifications.

I guess the inertia of the bolted on cam section is the issue for long term use. When you give it a blip it will effectively tighten the bolt for you, but when the cam slows down upon throttle release, the end of the cam wants to keep spinning fast and this will act to unwind that bolt. As you mentioned a tack weld might help, but that could introduce an imbalance. Slow winding down of the rpm would help, too, but not as much as that replacement cam you ordered. Did you order a top end gasket kit, too?
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I've already rebuilt the top end along with new rings and valves sort of lapped.... they didn't need much but it was a "why the hell not?" ...a few weeks ago. I won't be going that far in to remove the cam shaft. But I will be addressing the clutch cover inconstancies. Likely just gauged from the previous guy. I'll use some Honda bond on the case and then a little Ultra black on the cover sides which should sandwich the gasket plenty since it's already saturated with oil by now.

I ended up drilling and welding a small plug.... With material removal and then filled and filed, it's fine. I then threaded the redloctite stud into the camshaft body and it was very firm. That part never came loose earlier. Then I left all thread protruding from the exposed end where a washer and locking nut can be put on. Its almost unnoticeable. It was late so couldn't start it up but with the Killswitch on off, I spun it over a few times and it looked smooth. I think when I remove it, I'll drill the cam shaft and tack weld it from the other side too.

If it's true, it'll be a good emergency part.

I plan on pulling the bowls and adjusting the float in a little bit and then seeing if it wants to play nicer at 1/4 throttle without stumbling
 
stl360+450 said:
That's a win. And it was nice seeing that satisfied grin when it fired up and held idle on its own. Nice work.

The tank paint looks pretty good. I'm not a fan of the original tank decals for the 360, so a nice solid color seems like an upgrade to me when the bike has other modifications.

I guess the inertia of the bolted on cam section is the issue for long term use. When you give it a blip it will effectively tighten the bolt for you, but when the cam slows down upon throttle release, the end of the cam wants to keep spinning fast and this will act to unwind that bolt. As you mentioned a tack weld might help, but that could introduce an imbalance. Slow winding down of the rpm would help, too, but not as much as that replacement cam you ordered. Did you order a top end gasket kit, too?
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You nailed that with the inertia of the two pieces and at those rpms it makes sense.

That tank color it's surprisingly ok and if I wanna remove the small tank slap dent at some point, I'll prolly strip it and clear it. My sprayer did the frame very well so I think it'll look good. The decals are kinda whatever, but something like the gull wings would be sweet.. Or just Bondo em and go with a smooth aluminum looking finish later.

I'm the type to do the work and tinker until it works so I don't mind cracking those carbs in the living room while watching tv and then retesting the next day for a week. By end of April it'll be dialed in no doubt.

When I get home in a little I'm gonna wrap the baffle while the battery charges and then reconfirm my tach sensor wire.... I think it needs a signal from the coil. I ordered the 5 wire sparck moto regrec cuz my 4 wire wanted to draw power from the battery while it was off bc no sensing wire to tell it to turn on or off or what voltage my battery was at.
I'll get that wired in next week when it comes.

Otherwise, I'm a happy camper. My neighbors all watch me tinker and tell me they wish they knew how to do this stuff. It's a great hobby with tons of learning opportunities and fun rewards at the end. Also after a few weeks I cranked my FZR600 under that cover in the video and it fired right up and sounded anngggrryyy . Riding season is here in FL now minus this BS cold snap
 
https://imgur.com/a/jlfi4bV

Fellas (and ladies?), check out the gremlin idling strong WITH the repaired crankshaft. The new one arrived over the weekend, but before I went out of town, I used some all-thread to red loctite into the tapped hole in the crankshaft. Then I cross-drilled a hole in the broken off tip and used more allthread into it and tack welded it and then filed it smooth. then used more red loctite and threaded that piece onto the stud I inserted before, and assembled everything as normal, using the stock washer and a nut to keep it in place.

Immediately it cranked and has been rock solid with revs way up in the range. I'm still getting some pops around 1/4 throttle and up until full throttle really kicks in, but I believe that's carburetion possibly.

I've reset the floats to 20.5, balanced the carbs and then syncd them by ear and using the tach (but i will put the vac gauge on eventually, maybe tomorrow)....and it's idling strong and revving pretty great in Neutral. I was running very rich earlier, and adjusting the floats made a noticeable dif after a plug chop...... I'll hafta fiddle some more, but I want the popping to go away bc I don't wanna piss off my neighbors. I know I need to tack weld a few pin holes in the exhaust, but they are small and not likely enough to disrupt the flow that much. The 8 inch louvered baffle is lightly wrapped with fiberglass and it's sounding and feeling pretty good minus that midrange stumble.

Carbs current state: 35 idle jet, 2 small needle shims, 68 primary, 112 secondary, 20.5mm float, and 1 7/8 turns on the mixture screws...pod filters with 4.5 inch tubing stack extension NOT blocking airways, custom early Y merge exhaust ending about 6 inches in front of the rear tire (but plans to extend and hang a shorty megaphone if this continues to be problematic.
 
It is impressive, DLo, I must admit.

I'm hearing what seems to be a lot of noise from the points area, although I grant that adding the points cover would reduce that some, as would lowering the idle.

I remain concerned about how this will play out. Will all that chatter wreck your cam journals and bearings prematurely? Will the weld or red loctite give up at some point? Nobody knows.

I would put this cam in your trophy case and get the good cam into the game.

I like the exhaust.
 
stl360+450 said:
It is impressive, DLo, I must admit.

I'm hearing what seems to be a lot of noise from the points area, although I grant that adding the points cover would reduce that some, as would lowering the idle.

I remain concerned about how this will play out. Will all that chatter wreck your cam journals and bearings prematurely? Will the weld or red loctite give up at some point? Nobody knows.

I would put this cam in your trophy case and get the good cam into the game.

I like the exhaust.
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Yeah for sure gonna do the swap, but in a pinch this one will get me by. As far as the noise, I don't think it's exactly coming from the points area....just the overall chatter of the bike in general and maybe the enclosed area amplifying the sound of running. The header is right there too and of course the tappet covers. I don't recall it being any more noisy than it was before, and I took at look at everything before I put it all back together when I did the rings, and there wasn't excessive marring or wear....and surely a broken tip wouldn't affect the bits inside the cover.

I hafta cut out the test parts of the exhaust and reweld in a mandrel bent 112 degree section to clean up the look and get rid of any holes where the Y bends under the belly of the bike. Just changed oil today, and the exhaust doesn't interfere with accessing it, so I'm stoked that I was able to put together something like this in a relatively short time.
 
What did you adjust the valves to? Could be those creating the chatter - I damage it’s slightly louder than normal (although cell phone camera mics aren’t the greatest).
 
EzPete said:
What did you adjust the valves to? Could be those creating the chatter - I damage it’s slightly louder than normal (although cell phone camera mics aren’t the greatest).
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hair over .002 (.05mm) and .003 (.08mm). That part I have zero concerns.... I've set valve lash on SOHC, DOHC, shim over bucket, all kinds of stuff.... least of my concerns. These valves are spot on, and I believe my timing is nailed as well. Done visually and with a connectivity as an indicator. After a little more carb work, I'll be likely swapping the cams to put the non-janky-fixed cam in there, and the valves and timing will get reset again.

I'm still working on both sides of the carb tuning equation.... i can hear the exhaust note and when it stumbles a bit in neutral with revs, so I'm tuning the baffle and glass wrap, which I think I'm good with currently. Then idle, which you can tell seems to be strong and steady.....off idle to mid throttle seems to be where I get my first hang up with some hesitation and farting, and when I hold there it'll sometimes clean up, but sometimes not until I crack it wider, and then it's okay but some popping at WOT.

I'm looking at, in order:

  1. 1 step hotter plugs (worked well on my street bike w freer flowing shorty can and exposed pipes plus slightly bumped jetting).
  2. Going back to one needle shim, though the flat spot right off idle seemed to improve when I added the second ---- but I think my mix was off then, and now I could recheck with nothing else changing and see (easy with the carbs still on the bike and just popped out of the boots).
  3. Swapping 68 primary to 65. PJ mentioned that people do this when they seem to be running rich or fouling plugs....I think if this current setting doesn't burn better paired with hotter plugs, it could work to keep from dumping excess fuel while it transitions to the primary and then secondary. If I can meter the primary a little better, I think I can keep it from spending as much time in a rich portion of the circuit if there is one.
Thoughts are the popping is for sure lean condition but then he gurgling screams rich, so I need to smooth out the transitions from one part of the circuit to the next and along each area where they overlap. larger pilot, less mixture turns, one needle shim, smaller primary, stay with 112 main unless popping at nearly WOT, then I know 115 or higher (which is on the way)
 
Fellas, got some 65 primaries in the mail, and looking to swap them cuz im fouling plug after idling for a bit....and even when riding, i was gurgling rich to the point it stumbled and couldn't recover, and then pulling the air filters showed fuel in the carb body mouth.

ran some aftermarket 38 mains with proper crossdrilling holes, and it idled and revved strong, but only 3/4 turn out.....still got popping after about half throttle. removed my shims cuz the bike ran worse and worse the higher I shimmed it.... could possibly have bad emulsion tubes

im currently on a 112 secondary main, and I was under the impression that the shorter exhaust with a wrapped baffle would still be less restrictive than the previous repaired stock exhausts. might go back to 110 to see if I can lean out the top top, but I think at wide open I'm possibly still on the lean side.

thoughts: before swapping anything else, should I keep what ran strong, and adjust the float height to lower the fuel level a tiny bit in the bowl or go the opposite way? needle is 1/4 throttle to 3/4 and shimming was definitely not the right move, so I need less fuel in that stage. and then the back end of that was popping some....if i change other stuff, maybe 115 secondary, 65 primary, leave needled unshimmed, 38 or 35 main works fine (35 with newly properly drilled cross drilling works at 2-2.5 turns out. 38 works at 3/4 turns out).

I feel like I'm on the verge, and my understanding of carbs is that one change will affect the other, but I'm trying to think of them the same way you gain stage audio.... if I slightly increase the idle jet, i need less needle and less primary main jet flow, then faster refill of the bowl and a larger than stock secondary main to account for the major increase of air flow at nearly WOT (popping after the bogging and bubbling clears up).

IDEAS?
 
stl360+450 said:
It is impressive, DLo, I must admit.

I'm hearing what seems to be a lot of noise from the points area, although I grant that adding the points cover would reduce that some, as would lowering the idle.

I remain concerned about how this will play out. Will all that chatter wreck your cam journals and bearings prematurely? Will the weld or red loctite give up at some point? Nobody knows.

I would put this cam in your trophy case and get the good cam into the game.

I like the exhaust.
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Go ahead and say "I told ya so". Got a little excited and didn't recheck that cam repair and it started to spin loose throwing off my timing and breaking my left point rocker....🥴

Got a new point on the way along with a point plate. New cam will go in after hopefully I can load it in my SUV and tug it home or else I have a long night ahead of me 😂

Oh yah and if anybody can explain why the cafe racer shorter clutch cable keeps working and then not working suddenly that'd be cool. I think it's missing the retention accordion type thing by the actuator that keeps it under tension and prevents it from coming loose?

Sheesh.
 
dlogreen said:
Go ahead and say "I told ya so". Got a little excited and didn't recheck that cam repair and it started to spin loose throwing off my timing and breaking my left point rocker....🥴

Got a new point on the way along with a point plate. New cam will go in after hopefully I can load it in my SUV and tug it home or else I have a long night ahead of me 😂

Oh yah and if anybody can explain why the cafe racer shorter clutch cable keeps working and then not working suddenly that'd be cool. I think it's missing the retention accordion type thing by the actuator that keeps it under tension and prevents it from coming loose?

Sheesh.
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I don’t have that accordion boot on any of mine. Sounds like your actuator might be near the end of its throw on adjustment and hanging up at full extension.
If that’s the case, rotate the adjuster to give it a little more pre-load. It can happen when the free play is a bit short.
 
dlogreen said:
Oh yah and if anybody can explain why the cafe racer shorter clutch cable keeps working and then not working suddenly that'd be cool. I think it's missing the retention accordion type thing by the actuator that keeps it under tension and prevents it from coming loose?

Sheesh.
Click to expand...
The 360 shares the clutch lifter mechanism with the 350 and that might be what you're experiencing because of the design. It has to be dialed in the right way or the clutch lever can pull it past its range of operation in the front sprocket cover. Here's a link to the best method to use for proper adjustment within its operating range.



1775086887610.png
 
ancientdad said:
The 360 shares the clutch lifter mechanism with the 350 and that might be what you're experiencing because of the design. It has to be dialed in the right way or the clutch lever can pull it past its range of operation in the front sprocket cover. Here's a link to the best method to use for proper adjustment within its operating range.



View attachment 56512
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I already read that the motion pro cable housing is too long and preloading the clutch too much. So I took off the lock nut at the lever and it worked great but something is causing it to not stay that way and I'm wondering if it's my routing possibly. Any chance that movement down by the mechanism could cause it to shift? I followed two different manuals and even the CM one just to try something different after checking everything worked well.... Is it possible I have worn ramps and need a new actuator?

I worry about that when I get the bike home. For now I'm just brainstorming
 
dlogreen said:
Go ahead and say "I told ya so". Got a little excited and didn't recheck that cam repair and it started to spin loose throwing off my timing and breaking my left point rocker....
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That's not how we do things on this forum — there's no need for any of that.

It's a bummer about the failure, but you did successfully MacGyver your bike back to life and it lasted long enough for a full episode. I still call that a win.

Bring on the replacement cam and let's go!
 
stl360+450 said:
Can you describe how the behavior changes? Does it lose tension? Get too tight? Do you ever hear a pop from the actuator in the cover?
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All of the the above. It'll be perfect and I can ride it easy and shift and it's great... Then I might hit a bump or go over a high speed bump and it'll start getting nonresponsive. Then I'll adjust and it'll do the pop. Then reset and loosen and then it'll work and then rinse and repeat.

Also I know y'all are great. Just trying to keep a positive and playful attitude.
 
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dlogreen said:
Also I know y'all are great. Just trying to keep a positive attitude.
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Right on.

dlogreen said:
All of the the above. It'll be perfect and I can ride it easy and shift and it's great... Then I might hit a bump or go over a high speed bump and it'll start getting nonresponsive.
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The clutch and cable adjustment should not be affected by bumps or anything of the sort. Something must not have been right with the setup.

Without the lock nut at the handlebar, could the cable be falling out of position at the lever? Seems like it would be obvious if that were the case.

I guess the pop is the actuator going too far and slipping out of position, which would reduce cable tension. This would seem a more likely scenario. You mention multiple manuals as well as CM. Do you have the proper CB360 Factory Service Manual?

I'm including the Owner's Manual description of the clutch adjustment.

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Battle scars! One for me, one for the beast. Lost my grip and stumbled bringing it down from the cargo area with the rear wheel already down. It bounced when it hit the ground and the rebound got away from me. Cheapo Amazon brake lever.... I'll have another here tomorrow.
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