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Author Topic: All Show, No Go - Little Help (Maybe a bit more...)  (Read 1714 times)

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Offline Gman

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All Show, No Go - Little Help (Maybe a bit more...)
« on: August 29, 2015, 11:37:02 AM »
So, '76 CB550K.  Stock airbox 4-2 exhaust.  She was running, but had lagging pick up under hardish throttle, particularly as she warmed up.  Wanted to get it running right, so went through the trusty 3k tuneup: 
Air cleaner clean
New ND-X whatever plugs (they are the proper ones), properly gapped. 
Cam chain adjusted. 
Tappets adjusted. 
Clipped ends of plug wires and put boots back on. 
Tested coils - all good.  Confirmed spark on engine block.
Points (TEC) gapped.  1-4 timing set, but couldn't get 2-3 breaker based on available adjustment range.  Had a spare pair (Daicrappi).  Put them on and, predictably, couldn't set them. 

Soooo, aqcuired a used, but really good shape TEC points plate with TEC points that look to be in fantastic nick.  Put it on, gapped points, set timing, and... nada.  Don't seem to be getting any spark.  (Battery is solid.)  Laid a spark plug on block and put #4 plug wire on it.  No spark. Same w/#3 wire. 

Went back to points and was checking timing (w/multimeter) and wasn't getting the little spark at the points when rotating the crank.  Then, when poking at one of the condensers w/lead, something loud popped (like a backfire).  Not sure if I artificially made a plug spark and it fired or what.    Checked fuses, battery, connections, plug wires and boots for looseness (and scorch marks).  I'm befuddled.

Ideas?
« Last Edit: August 30, 2015, 01:14:26 PM by Gman »
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Old Scrambler

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Re: All Show, No Go - Little Help
« Reply #1 on: August 29, 2015, 11:47:32 AM »
You found the problem........condensers............also a likely worn points-cam and or fiber...........or its wobbles and needs to be trued to the crank...........
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Offline Gman

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Re: All Show, No Go - Little Help
« Reply #2 on: August 29, 2015, 12:01:51 PM »
OS - thanks for the reply.

Cam is likely fine, as it was running w/the old (TEC) plate.  Any input on aftermarket condensers (I have a set), or should I pull the ones off the old plate and re-use?

Peace,
G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help
« Reply #3 on: August 29, 2015, 12:33:29 PM »
Put on old condensers.  Still won't fire up.  Hmm...
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline calj737

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Re: All Show, No Go - Little Help
« Reply #4 on: August 29, 2015, 01:04:50 PM »
New condensers
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Gman

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Re: All Show, No Go - Little Help
« Reply #5 on: August 29, 2015, 01:12:50 PM »
Yup - guess that's the next step.  Thanks, Cal.

Will keep you posted.
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help
« Reply #6 on: August 30, 2015, 12:59:38 PM »
OK - tried both the TEC condensers off the plate I bought, my original TEC condensers, and the new aftermarket ones.  No starting w/any of them. 

What would be a likely culprit(s)?  Is there a connection in the run switch that could have gone south?  Any other likely connections?  As it is, I've looked over the wire connections to/from condensers, coils, etc.  Other possibilities?

Thanks.
G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help
« Reply #7 on: August 30, 2015, 01:09:41 PM »
With ignition to Run, I'm getting juice to the condenser (per multimeter).   If I turn the crank and have #4 plug on the block, it should spark, correct?  I'm not getting anything when cranking via starter and/or by hand.  So, issue w/coils?
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Powderman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #8 on: August 30, 2015, 01:45:50 PM »
Are you getting spark to any plug? If so switch that coil with the other and see the issue moves to another plug. If it's 2 plugs out, it's probably coil related.
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Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #9 on: August 30, 2015, 01:55:11 PM »
PM - thanks.  I did try the 2/3 plugs yesterday and nothing, but I'll try again just to make sure.

Peace,
G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #10 on: August 30, 2015, 02:13:43 PM »
Checked for spark on #3.  Nada.

Also pulled apart Run switch to check for continuity when 'on'.  Switch is fine.  Not sure where to start tracing.  Any/all ideas welcome!

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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline calj737

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #11 on: August 30, 2015, 02:17:59 PM »
You need to verify that there is power to the coils, 12v on the BLK/WHT coils. Then, if you have power, confirm spark on both 1/4 then confirm on both 2/3. Your replies have been slightly unspecific as to whether you have spark at both plugs on the same coil.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #12 on: August 30, 2015, 02:20:02 PM »
Cal,
Thanks - no spark on #4 or #3.  Assuming that if those don't spark, then #1 and #2 are also not sparking.  Will go check for power to coils now.

Peace,
G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline calj737

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #13 on: August 30, 2015, 02:22:02 PM »
Hold tight there, gman. Assume nothing, test everything. Cylinders 1/4 are served on the same coil, 2/3 are served from the other. If you have the left coil wired to 1/2, and the right coil to 3/4, there's 90% of your problem.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #14 on: August 30, 2015, 02:29:17 PM »
I'm dumb, but hopefully not THAT dumb. :)

I checked plug #4 for spark.  If that's not getting spark, then I'm assuming #1 also wouldn't be getting spark.  Could be wrong, but when starting the bike, nothing fires.

I also checked plug #3 for spark.  Assume #2 is also not getting spark.

Just checked juice to coils and it's flowing.  Will go check for spark on #1 (for 1/4 coil) and #2 (for 2/3 coil). 
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #15 on: August 30, 2015, 02:43:00 PM »
Nothing on #1 or 2 either.

So with power to coils and power to points plate, it must be something in between.  Could the points be bad somehow?  Something I did while swapping the points plates out?  Could the timing be 180 off?  I didn't disassemble the spark advance, but did take it off the clean it.  I'll go verify...

G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #16 on: August 30, 2015, 02:53:00 PM »
May be on to something - even with the points open, there is current from one side to another.  If that's the case, the coils would never get a jolt.  What would cause that?  Points put on incorrectly?  I didn't take them off the plate when I put it on - just plug and play (or not, in this case).  Should the two sides of the points be insulated from each other?  I'm assuming that's what the little fiber washer thingies are for...
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters

Offline calj737

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #17 on: August 30, 2015, 03:23:19 PM »
Look carefully and see if the small grounding wire is contacting the plate and preventing them from firing the coils.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Gman

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Re: All Show, No Go - Little Help (Maybe a bit more...)
« Reply #18 on: August 30, 2015, 03:50:03 PM »
Will check the grounds in a bit - need to take a break and get dinner on the table.  Thanks for the help.

G
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'76 CB550K
Stock airbox, MotoGPWerks 4-1, HondaMan ignition, Lesters
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