New Member, old bike problems

O

OldBikeSailor

New Member
Hey there,

I had posted in another thread but realized I had hijacked it whoops.
I'm working on my second bike restoration here in sunny Rhode Island. First bike is a 1974 CB450, bought for a song, basically a little electrical here, some cleaning and brakes there and she's good and reliable.
Me being overconfident in old bikes decide to buy a 1972 cl100.... in a box. I got a new wiring harness, battery, and the rest was all there.
I get the bike together thanks to a scan of the service manual and it starts! But doesn't run long and bogs down from half throttle all the way to full throttle.
Tonight I went to check the static timing and spark advancer for the tenth time and realize that I was no longer getting power to the point plate. The wire is getting power and the plate is right up until I mount it, then nada.
Anyone experience this before?

Thanks
 
Sounds like your points wire is grounding out somewhere on the engine case or cover. Make sure the plastic and metal washers are installed in the correct order on the points assembly, there is a very specific way the wire needs to be insulated. When you route the wire, make sure any exposed copper isn't contacting anything it's not supposed to. Make sure y got a gasket on the cover some people use 2 to get some extra clearance for the cover


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OldBikeSailor said:
Hey there,

I had posted in another thread but realized I had hijacked it whoops.
I'm working on my second bike restoration here in sunny Rhode Island. First bike is a 1974 CB450, bought for a song, basically a little electrical here, some cleaning and brakes there and she's good and reliable.
Me being overconfident in old bikes decide to buy a 1972 cl100.... in a box. I got a new wiring harness, battery, and the rest was all there.
I get the bike together thanks to a scan of the service manual and it starts! But doesn't run long and bogs down from half throttle all the way to full throttle.
Tonight I went to check the static timing and spark advancer for the tenth time and realize that I was no longer getting power to the point plate. The wire is getting power and the plate is right up until I mount it, then nada.
Anyone experience this before?

Thanks
Click to expand...

Sorry adventurco but that may be wrong. His connection and points could be working correctly.

Power takes path of least resistance.

Thus, Oldbikesailor, your findings are correct. As long as your points are closed when the plate is installed on the engine. you WONT read power. On the movable contact or wire.

Turn engine slowly CCW until the points open. Then you will read power again. This is proper operation.

The 6v will take easiest path to ground through the closed points. It wont take the long way through your meter. Once the points open, power must go to ground through the meter...cause it cant go through open points.

After setting static timing are you dialing it in w a strobe light? You must finish timing adjustment w a strobe light.
 
Unless of course your connection is made wrong as adventurco stated. And the wire is hooked up incorrectly at the movable contact connection and grounding through the points plate. (no power reading on the movable contact w points open or closed).

The adventurco is right! HA.
 
Also, when testing this stuff. Dont leave key on with points closed for very long. This will heat up the coil and could fry it. Also, the leaf spring on the movable contact, could overheat and loose some of its temper.
 
If the bogging problem still persists once timing and advancer operation is correct.

Check the main jet in the carb for clog. It could be overheating due to lean condition.

Another check to make. "Plug chop" Run engine in the "bogging zone" for a bit 30-45 seconds. Then WITHOUT releasing throttle. Kill the engine. Coast to a stop and pull the sparkplug. If it nice and clean crisp white. Its running too lean.

Clean main jet or raise needle or go w larger jet. I think I have a 105 installed and needle is on center clip.

If the plug is black. Then its running too rich. Lower needle or smaller main jet.
 
Wow thank you for all of the quick replies!
I did try and open and close the point to check for a open/close circuit unfortunately there was none. Im going to upload some pictures of the plate and the circuit light in various positions this weekend.
Thanks again
 
Yep, then as adventurco said. Check the wire to movable contact connection. its easy to get those tiny insulating washers in wrong. Or your connector is touching the plate.
 
Oh and sorry I wrote 12v earlier. Stock 72 cl100 is a 6v system. I corrected it above.
 
So you guys were right. The plastic(?) washer had melted and was connecting the plate. I replaced those parts and put it back in and static timed it. Good spark, no start. Pulled the carb and am cleaning that again and rechecking the float height. Jets were clear. Had some backfiring and sputter running but cant get it to idle. Will keep updating as I get progress.

Attached some pictures of the day I got the bike, the bike put together, the melted washer, and the reassebly
 

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Adventurco gets all the credit for that one. He called it. ;)

Try adjusting the A/F mix screw to 1 & 1/4 turns ccw from bottom. and try it just keeping choke cracked open just a very little bit.
 
Mine was identical. Blue w white and I think orange stripes. Only yours has a whole lot less rust.
 
Nice, I like the colors and trust me there is plenty of rust and wear, that ones the glamour shot.
Today I pulled the cam at tdc and found it to be bone dry in the there. Some dried up moly paste from the look of it. Is that normal or is it supposed to be a oil wet environment?
Thanks again for any responses
 
You mean you pulled the rocker box off and there's no oil on the cam/rockers? That's not good. It should be coated with oil all up in there. If you haven't, remove the cam and check the health of the journals and camshaft sliding surfaces...if it was run dry chances are it's toast. Post some pics of what it looks like.

Open up the right hand cover on the crankcase and pull the cover off the centrifugal filter, it's probably chock full of crap.


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I decided to go ahead and pull the whole engine. Removed the head and found it to be dry. Looks like no excessive wear though. I found the oil passage hole and it was clogged up good. Cleaned it out checked the filter which was pretty clear.
One worrying thing I found was the spark advancer case was being ground down by the advancer. I ordered a new one and seal. Anyone have an idea of what could have caused this? Looks almost like the camshaft was riding down on the case.
 

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That camshaft looks shot my friend, do you have pics of the journals where it rides? The seal may have burnt up from lack of oil resulting in overheating.


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Dude that sucks! hoping the pic makes it look worse than it actually is. Yep post more pics.
 
Here's couple more pictures, looks like a matching ridge on both. On further inspection the was a lot of gunk where the camshaft fits into the rear of the head. Could that have cause it to ride cockeyed? Causing the wear? I attached some pictures. Looks like I'm going camshaft shopping?
Also when I went to put it back in so I didn't lose track of anything I followed the manual instructions and followed the lobe shape and went to turn it one revolution but it seemed like there was a lot of resistance from the valve springs.
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P.s. This app is great


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Yep well we know that camshaft is pretty much toast but what does the actual head and rocker box look like where that thing sits?


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