CB360G yard find — ongoing project log

Post what the chromer says. I'd like to rechrome my headers, but no local ones. Didn't want to ship off my header pipes and find out it can't be done. The stock head pipes are double wall and I don't know if that is an issue or if the residue internally is an issue. I heard some chromers don't like exhaust components because it contaminates the chemicals.
I've heard the same, so I'll start by trying to clean them as much as I can. That may take some time, but I'll follow up when I get to the point of seeking replating.
 
I made a roto-rooter brush one time out of an old clutch cable by smashing a nut about 2 inch from the end then splaying out the wires of the cable, which was about 2 feet long and stuck that in my drill to ream out a carboned up heat riser tube for an air cooled VW manifold. It would work great for cleaning the inside of a header but would probably get hung up on internal baffles of a muffler.
 
I made a roto-rooter brush one time out of an old clutch cable by smashing a nut about 2 inch from the end then splaying out the wires of the cable, which was about 2 feet long and stuck that in my drill to ream out a carboned up heat riser tube for an air cooled VW manifold. It would work great for cleaning the inside of a header but would probably get hung up on internal baffles of a muffler.
I'll have to try something along those lines, likely in combination with chemical methods. Thanks for the tip.
 
I'll have to try something along those lines, likely in combination with chemical methods. Thanks for the tip.
Raw gas does dissolve a lot of the baked oil residue to flush it out during brushing. Plumber's pipe brushes come in different sizes, if you can figure a way to attach a long flexible handle. Maybe a cheap drain snake too.
 
The problem with re-chroming pipes is the carbon inside them.
With a double skinned pipe it's almost impossible to completely clean out so very few chrome plater's will touch them.
Some companies, when it's time to clean out/change vat will re-do exhaust pipes but rarely guarantee a 'perfect' finish.
There is also a problem with exhaust pipes that 'ordinary' chrome doesn't last very long due to regular cyclic heating and cooling.
OEM use whats called 'microcrack' plating (friend of my brother was a plater at Rexel chroming stapler parts for years and knew about these things, Saturday morning specials when no managers present ;)
 
Noticed a problem on my ride home from work today, see exhibit A below.

elSsB9M.jpg


Not sure when this happened, but there are some terrible bumps that I've been driving over daily where a road crew put a mound of asphalt into the seams on a bridge, creating the equivalent of a sharp speed bump on a road where everyone is doing 35-45 mph. I would really like to know how long it took me to notice.

I'm going to look at billet top bridges in comparison with OEM. I'd prefer whatever seems beefiest. Recommendations welcome. SpeedMotoCo has one option with holes for the risers.
 
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That's was a common problem back in the day. Careful tightening the clamp bolt. Don't over torque. Either find a used one on the usual bid sites or check out CommonMotor.com Triple Clamp. New Clamp. Late model CB350 upper triple works too.
 
Did you use a torque wrench when assembled ? Many people over-torque these bolts, with the above result. Since the P/N number is 53200-333-000B (CB350F), I might have one for you if interested.
 
Careful tightening the clamp bolt. Don't over torque.

I don't think I've touched that bolt in the last 8+ years, but I could have over-tightened it at the time.

Did you use a torque wrench when assembled ? Many people over-torque these bolts, with the above result.

I assembled it in the "before times" (before I knew anything about motorcycle maintenance), so it is very likely that I did not use a torque wrench. This is the bike that got me started with repair and maintenance around 2014.

Since the P/N number is 53200-333-000B (CB350F), I might have one for you if interested.

It looks like there are plenty available here. I'm also curious about the billet style replacements. Thank you for the offer in any case.
 
The billet style are nice , but they don't have the mounting holes/brackets for the gauges. It's for the young folk stripping the bike to make a Café Racer. "Don't need no stupid badges Gauges"
 
Actually, they do have pre drilled mounting holes for gauges on the bottom. Probably with mini gauges in mind though

I was just noticing that they don't seem likely to fit the stock gauges.

The billet style are nice , but they don't have the mounting holes/brackets for the gauges. It's for the young folk stripping the bike to make a Café Racer. "Don't need no stupid badges Gauges"

Good point. So, in this case those guys in Houston looks better than CNC. Thanks for sharing that reproduction part from those guys in Houston. It looks like it could be worth trying. If their claim about better materials and manufacturing is true, it's a win.
 
Thinking back several months, my CB360G fell over on soft asphalt last August while parked on the center stand. It landed on the right side and bent the brake lever substantially. I can't help but wonder if that incident is also connected to the top bridge failure.
 
Thinking back several months, my CB360G fell over on soft asphalt last August while parked on the center stand. It landed on the right side and bent the brake lever substantially. I can't help but wonder if that incident is also connected to the top bridge failure.
I suppose if it was already overtightened, the impact might have been the last straw.
 
I was just noticing that they don't seem likely to fit the stock gauges.



Good point. So, in this case those guys in Houston looks better than CNC. Thanks for sharing that reproduction part from those guys in Houston. It looks like it could be worth trying. If their claim about better materials and manufacturing is true, it's a win.
I've had 3 bikes with 3 cracked ones and bought 3 from those guys in Houston, as I can't see buying originals with known weakness.
 
I did a high side at about 50 mph on my CB360t. Forks twisted in the triple clamps, clutch lever broken, shift lever bent, signal lights upset. Triple clamp survived. So they are actually pretty tough if not over torqued. Can't say the same for clutch levers and shift levers though. Bikes tough, I straightened the forks out with the front wheel between my knees and twisting the handlebars. Unbent the shift lever and refrained from using the clutch. I did have a spare at home (about 3 miles away) so was back to riding. That's when I bought a full face helmet and started ATGATT. You don't get lucky more than once in a situation like that.

The bikes are pretty tough all around though.
 
I now have the reproduction top bridge from those guys in Houston and I'm planning to install it tomorrow.

VL3KB77.jpg


I don't want to under- or over-torque the 8mm bolts for the clamps. The torque standards in the service data don't list these bolts specifically, but I've found in another manual that 8mm bolts should be torqued to 13-18 ft-lbs (17.6-24.4 Nm) while 8mm flange bolts use 17-22 ft-lbs (23.0-29.8 Nm). The bolts provided by those guys in Houston are 8mm socket head (Allen drive). Would 15 ft-lbs (20.3 Nm) be reasonable?

skPGMx6.png
 
I now have the reproduction top bridge from those guys in Houston and I'm planning to install it tomorrow.

VL3KB77.jpg


I don't want to under- or over-torque the 8mm bolts for the clamps. The torque standards in the service data don't list these bolts specifically, but I've found in another manual that 8mm bolts should be torqued to 13-18 ft-lbs (17.6-24.4 Nm) while 8mm flange bolts use 17-22 ft-lbs (23.0-29.8 Nm). The bolts provided by those guys in Houston are 8mm socket head (Allen drive). Would 15 ft-lbs (20.3 Nm) be reasonable?

skPGMx6.png
Will you use Never Seize or thread lubricant ?
 
This is another area I don't use a torque wrench for, I just tighten them with a good feel. I know that's nearly impossible to describe in words, but it's how I learned to work on bikes with my father who only used a torque wrench for engine rebuilds. As a side note, it's interesting that the machining on the new one seems a little rough-finished, as well as the tops of the handlebar mount holes being bare aluminum. I believe those spots are visible with the bars and mounts in place, and it looks odd to me.
 
I'll be interested in any tips or tricks when you install it. I picked one up just before Christmas when they were on sale but haven't gotten to that end of the bike yet. But it won't be long......
 
This is another area I don't use a torque wrench for, I just tighten them with a good feel.
That's what I did previously, but I want to rule out human error this time in case I over tightened the bolt the last time.

As a side note, it's interesting that the machining on the new one seems a little rough-finished, as well as the tops of the handlebar mount holes being bare aluminum. I believe those spots are visible with the bars and mounts in place, and it looks odd to me.
I don't think that surface will be visible, but, if so, only a little.

Screenshot_20240329-183041.png
 
I didn't use a torque wrench on either of the two those guys in Houston tops I've installed. Most of the fork stress is handled by the steel lower tree. The alloy tops are just to stabilize the fork tubes so torquing is not critical. I thought I saw a note from those guys in Houston, possibly on the ad page, with recommended value limit.
 
When I was a Truck Mechanic, I was good at estimating torque without a torque wrench. I stripped and broken a lot of screws/bolts before I got there.
If you aren't wrenching everyday, a torque wrench is a good tool. Oddly, Harbor Freight Torque Wrenches have good reviews and test well for accuracy. a 1/4 torque wrench is under $20 and in my case, was free on a special. You will not go wrong using one. Aluminum cases and small fasteners are easy to over-torque unless you are wrenching daily. 15 Ft/Lbs is fine, within the range. After you tighten them a few times, you will get a feel for the proper torque. Till then, use a torque wrench. Can't hurt.
 
I can't point to a current study, but where I used to work, our engineers were fanatical about getting the torque correct. They claimed that people who think they have an educated arm and can tighten fasteners correctly without a torque wrench usually error on the "too tight" side, rather than "too loose". Just sayin'
 
I can't point to a current study, but where I used to work, our engineers were fanatical about getting the torque correct. They claimed that people who think they have an educated arm and can tighten fasteners correctly without a torque wrench usually error on the "too tight" side, rather than "too loose". Just sayin'

I've been wondering about this point. I was even thinking it could be fun to start a thread where a test is devised to check torque feel and anyone who wishes posts their results.

I can't say for sure that I did or did not over torque the clamp on the top bridge. I don't think I used a torque wrench. I can say that I've broken at least a handful of 6mm bolts, one clutch pressure plate for my CB750, and one handlebar clamp (somehow) in the 10+ years that I've maintained my vintage bikes and most of that was in the first few years.

I also looked back at photos after my bike had fallen on the center stand in August while parked on soft asphalt in 100 F heat and the clamp was broken in one of the after photos. I figure it was a contributing factor. Nevertheless, I want to be more careful about being ham-fisted just as a precaution.
 
Some bolts and fasteners have a wide range of usable torque settings, and by guess/by golly torque by hand is acceptable. Head bolts, machines surface (bearing caps and the like) really should be torque wrench. The motorcycle has so many steel screws in soft aluminum, that low experience guys really should use a torque wrench. If you are removing side covers all day in a shop, you do get a feel for the right amount. But unless you are doing hundreds a day, a torque wrench keeps you from learning new curse words.

I trick as a former professional mechanic (Local 440 machinist and aerospace workers) I do is use the appropriate wrench. Small 1.4 inch drive for small screws. There are only a couple of places anything larger is needed, such as axle bolts. A stubby 1/4 inch drive wrench will be difficult to apply gobs of torque to. Problems arise when using 3/8 or 1/2 drive on the small stuff. Too much leverage.

Another miss for many is the use of loctite, antisieze, etc. This lubricates threads. Unless the spec specifically says the torque with Anti-sieze/ Loctite, the specs are for a clean dry thread area. Any oil or substance on the threads will even allow a torque wrench to over torque a screw.

In the whole scheme of things, best to use a torque wrench to avoid tears.
 
I installed the new top bridge on Saturday and I currently have the tank off for a little lot of internal cleaning. It was lined when I got it and not very well, so I doubled down and added another layer. I'm neither for or against liners, but decided to remove this one and try to clean the tank well enough to use without a liner.
  • Step 1: Acetone to dissolve the liner. This took a while and was messy.
  • Step 2: Phosphoric acid to remove rust. I added roofing nails and agitated the tank to help out. Still took a while. I bought some rubber stoppers at HD and they did a good job keeping things sealed while I was shaking the tank around.
  • Step 3: Drain, remove nails, and coat inside with oil. I noticed some flash rust this morning, so Steps 2 and 3 are being done a couple of times.
  • Step 4: install and fill with fresh gas. I plan to do this right after the last iteration of Step 3 to reduce the appearance of flash rust.
While the tank is off, I was hoping to address another minor annoyance: flickering tail/brake light, headlight, and neutral lights. Only the tail/brake light is LED. I have a small AGM battery on the order of 5 Ah and it is fully charged. I ran it on an auxiliary tank and tried adding a jumper wire from ground to the coil bracket with no effect. I wonder I need a bigger battery or should go back to an incandescent tail light. It didn't really bother me, but one motorist expressed his displeasure about it a month or so ago.

Additional Info: At idle, I'm seeing 13.0 to 13.1 V across the battery terminals. This bike has a stock rotor & stator along with the rec/reg from those guys in Houston.
 
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Quick question, did the 360 do away with the triple clamp gap washers?
For reference, the 450 has washers that go in the gap, they have a flat to clear the fork tube, and limit the squeeze stress on the Aluminum?????
 
There's something going on there, like maybe something involving the rec/reg unit. It reminds me of smaller bikes with lighting coils that only used the battery for a boost for the taillight and horn at idle, with the pulsations coming from the lighting coils in the alternator.
 
There's something going on there, like maybe something involving the rec/reg unit. It reminds me of smaller bikes with lighting coils that only used the battery for a boost for the taillight and horn at idle, with the pulsations coming from the lighting coils in the alternator.
This makes sense as there is no pulsing with the motor off. I guess the next steps I will take are
  • trying a larger AGM battery
  • trying an incandescent bulb.
If it's the rec/reg, I'll be happy to replace it with one that prevents the pulsing.

I've read in some other posts about adding a capacitor to counteract the pulsing. I guess this is an option, too, but I'd have to think about what amount of capacitance is needed.
 
Or a bad coil on the stator. There are 2 sets of coils on the stator. A group of 4 for low beam and all electrics, and a group of 2 for additional capacity for High Beam . Check stator for continuity and to ground.

A bad Rectifier could be losing 1/2 the AC wave also.

Check AC output on Stator and DC output on regulator/rectifier circuit.

Alternator Charging.JPG

Color Schematic CB360.jpg
 
I had that flicker and also blew some bulbs (both incand and LED) on my Benly. The rectifier wasn't very old but a cheapy. A new rec/reg fixed it but I also ran extra grounds to the bucket and from rec/reg to battery neg. I figure the lack of good grounds beat up the rectifier and caused early demise.
 
I now have the reproduction top bridge from those guys in Houston and I'm planning to install it tomorrow.

VL3KB77.jpg


I don't want to under- or over-torque the 8mm bolts for the clamps. The torque standards in the service data don't list these bolts specifically, but I've found in another manual that 8mm bolts should be torqued to 13-18 ft-lbs (17.6-24.4 Nm) while 8mm flange bolts use 17-22 ft-lbs (23.0-29.8 Nm). The bolts provided by those guys in Houston are 8mm socket head (Allen drive). Would 15 ft-lbs (20.3 Nm) be reasonable?

skPGMx6.png

The bolt should be at lower end of torque scale, 12~14 ft/lbs personally I thought they were 7mm but it's at least 15 years since I checked.
Didn't know Brendon was doing a repop of OEM, better than the 'flat' billet ones by a long shot.
 
Since Brendon is selling the top bridge; providing the bolt, nut, and washer; and telling you that it is safe to install with no "D" shaped washer; it would seem that he would also provide the torque spec. That way, if the new piece snaps, he would be more ready to stand behind his product. I would ask those guys in Houston, rather than getting people's opinion on this forum, educated as those opinions might be. I would then keep Brendon's answer on file somewhere.
 
Since Brendon is selling the top bridge; providing the bolt, nut, and washer; and telling you that it is safe to install with no "D" shaped washer; it would seem that he would also provide the torque spec. That way, if the new piece snaps, he would be more ready to stand behind his product. I would ask those guys in Houston, rather than getting people's opinion on this forum, educated as those opinions might be. I would then keep Brendon's answer on file somewhere.
You're exactly right, Ray, and I had the same feeling about the possibility of warranty replacement should the part fail. Earlier, @ballbearian pointed out that they do list the torque spec (12 ft lbs) in their installation tips and I followed it.

The CB360 does not use D-washers on the OEM top bridge, either.
 
^^^Yes, I see that now. I think you should be good to go. I'm curious though -- was there a gap after you tightened the bolts? I guess there is supposed to be one with that setup. I recently reinstalled the top bridge on my SL350 K0, using the D washers and it looks like this:

 
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