1971 CL450 build. (not fancy, but complete...)


"everyone has a plan…"
man, i appreciate any ideas! ANY ideas. -as i'm about at wits end.

only thing is- battery is brand new (which I know doesnt mean anything -never just assume an electrical component works)

and thru all this testing, Ive had a proper* 12v car charger hooked up to the batt. -so she's getting a solid 12V, even if batt is weak.

(*not a batt tender)

I ordered a new coil, and will play the old "swap known for unknown" game to make certain coil isnt shorting somewhere/sometime.


Loves Stock Airboxes
do you have a multimeter though? Its really simple to get the thing idling and then test battery voltage output. Swapping known for known works. I also try swapping things right to left to see if I can make the problem swap sides.

its possible (I could be so wrong here) That you could swap spark wires and a few of the leads on your current coil set up and effectively swap the coils without unbolting anything from the bike (would be a good way to tell if the coil was your problem. If the misfire jumps sides, then its the coil, if not . . . something else).

Again - I don't have the wiring diagram in front of me, but I **THINK** you can swap the leads coming out of the points and the spark plug wires and you've "swapped your coils" (my grasp on electronics is based entirely on my understanding of plumbing, which is quite a bit simpler - so elementary at best)


"everyone has a plan…"
again- appreciate ANY brain power someone is willing to put toward this thing.

i'm still waiting for the coil- so went out and tried some basic diagnostic stuff. first was- hooked an analog voltmeter up (neg in the cap/postive to engine) and turned the engine over. needle popped in a positive direction (up the scale) so that tells me coils were hook up correctly (power wire/points wire)

tested ohms across all points and two coils are identical -which kind of rules out bad coil. :(

but was sitting there thinking for a few minutes- (with switch in "on" position)… reached up and holy crap- one of the coils felt white HOT.

right now, i'm waiting for the damned thing to cool down- but could that be a bad ground?

harness dumping electrons into the coil, nowhere to go and so it heats up like a toaster wire?


'74 CB360, '71 CB450, '75 CB550SS
Hot coil means the primary winding is grounded. IE one of the colored wires going to the coil has a closed point. Either that or one of the point wires is grounding out some where.

It takes about 2 minutes to warm up a coil enough to kill it, just saying. Coils should only be ON for a few seconds, no more than a minute while you check the timing. Normally they are on for fraction of a second

Current flows from positive to negative, so BATTERY ---> switch---->kill switch---->coil---->closed points-----> Ground. Interrupt that anywhere in there and you get a spark IF you have a charged coil.


"everyone has a plan…"
if you look at the dates of the recent posts... you can see that the little gremlins were getting the best of me. weekends would go by, and i wouldnt even bother to look at the damn thing.

I was THIS -><- close to having things finished, and it was eating me alive.

well, I think I'm over the hump. turns out, it was a whole mess of little things.

carb float height in on right carb mysteriously went WAAY out of spec. one coil was still grounding (-but only when you tilt your head at an angle and looked at it with your left eye). one of the washers i used under the allens to fix the points was too big and threw the timing out. timing advancer worked with/against the bad timing to run really well above 2K... which made diagnosis difficult, a few loose bolts here and there... etc etc etc

basically just a thorough going-over. kind of like an algebraic equation. if you only have one variable, you can solve for "X" pretty easily. however- when you have 13 variables...

its a whole 'nuther problem.

despite this- she now runs, she idles, she revs... and for the first time in a VERY long time... she powered a rider around the block!

needless to say- i'm frikin tickled. pictures to follow!


"everyone has a plan…"
i know its a little cliche, but here are some before/after pics:





"everyone has a plan…"
a few more very minor things to clean up- extend the kick stand, look into some rear shocks that actually have some travel to them (this is like riding a 4x6!), mount the neutral switch and clean up the front wiring…

but for all intents and purposes… I'm gonna call this one done. she rolls, idles, stops, lights work, gauges read and light up… just went on her first real ride on public roads.


what a long strange trip its been.

thanks for all the advice/help and enthusiasm!


'74 CB360, '71 CB450, '75 CB550SS
I've enjoyed following your build, bike has turned out wonderfully, be more than welcome in my garage any time. ;) ;D


"everyone has a plan…"
just got contacted about a possible BOTM nomination!!!

immensely honored to have my little project even remotely considered.


New Member
This is outstanding, great work and a great final product. I assume that the exhaust on this is a one off custom? Or is this something that is readily available on the market?

Thanks for a fantastic read!

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