Author Topic: Ignition problems?  (Read 1787 times)

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Offline crazyxxhondaxx

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Ignition problems?
« on: September 23, 2014, 01:28:52 PM »
Hello all,

So I've recently finished rebuilding the top end of my 78 550, and now I've run into a road block.
After we'd finished the rebuild we noticed it had a miss, so last night i sat down to re adjust the points and try to work out why it was missing. After following the instructions in the manual to a T I only ended up making it worse. So I recruited my uncle to help out, and he couldn't get it worked out after 2 hours of struggling so we eventually had to call it quits.

The problem was when we went to use a tester no matter where we put the base the light wouldnt come on, does this mean I have a bad point? We were testing the 1-4 point, we never made it to the 2-3 point. Also when we could get the bike running the 1-4 point was arcing quite a bit, we checked and did the point gap about 4 times, and each time the 1-4 was arcing while the 2-3 barely sparked.

By the way, the plugs and wires are brand new,

Any help would be appreciated! But any tips on the points adjustments are welcome.
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Offline Old Scrambler

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Re: Ignition problems?
« Reply #1 on: September 23, 2014, 02:21:23 PM »
Sound like you are trying to set both sets of points by moving the points-plate......................assuming your light actually works.............concentrate on setting 1-4 and tighten the plate. Then adjust 2-3 without moving the plate or affecting 1-4...............
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Offline OldSchool_IsCool

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Re: Ignition problems?
« Reply #2 on: September 23, 2014, 06:23:36 PM »
Swap your condensers. If the big spark moves to 2-3, then that condenser is shot.
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Offline crazyxxhondaxx

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Re: Ignition problems?
« Reply #3 on: September 24, 2014, 12:32:54 PM »
Okay, it'll be a day or two till i get back to the bike, but quick question. As much trouble as this has been, and from what ive read from other posts it can continue to be a pain, should I invest in an electronic ignition? this is my pick right now
http://www.amazon.com/DYNA-IGNITION-HONDA-DS1-2/dp/B000WJJ4K6/ref=sr_1_1?s=automotive&ie=UTF8&qid=1411586900&sr=1-1&keywords=1978+honda+cb550+electronic+ignition
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Offline Vinhead1957

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Re: Ignition problems?
« Reply #4 on: September 24, 2014, 12:54:50 PM »
Many times it is the connection on the points itself. Ensure the wires to the points are not grounded to the base. If the points are open you should have 12V at the connection where the blue or yellow wire and condenser is. It is common and easy to accidently have it touching the base. Make sure there is no connection when the point set is open

Offline strynboen

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Re: Ignition problems?
« Reply #5 on: September 24, 2014, 01:06:06 PM »
a elektronic ignision must also be adjusted...so dont vaste your money..

.use a multimeter..if the coil  vire are taken off..the" biib" funktion are easy..turn to it stoops beebing..and the ignision point are there...it must be at the 1-4 mark firing..

renember it are vhen the knicker opens it fire....and turn the engine in the right direksion..and be shure the regulator/sentifugal not are turned a half turn..i have once put mine backverd inn..
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Offline TwoTired

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Re: Ignition problems?
« Reply #6 on: September 24, 2014, 01:28:44 PM »
There is no "need" to switch away from points, And the Dyna will just draw more power, without much , if any, spark improvement.   However, if you are unable to make the points system work, it could get you driving.

The points are a simple and basic electrical switch.  When closed they draw current through them, charging the coil.  Open, allows the coils to spark the plugs.  There are only two electrical connections.  One side connects to the engine case, the other connects to the coil.  Pay attention to the wire terminals on the points so they aren't allowed to contact the engine case, and be certain the insulation collar on the post is centered.

Once the connections are confirmed, rotate the crank so that the points are at their most open position.  Ignore the timing marks for now.  Set the mechanical gap to book spec.  If you apply power now, an attached light will shine bright as the lamp filament provides an electrical path around the point contacts.  Now rotate the crank until the light goes out.  This is where the 1.4 F mark should align.  The main plate screws are loosened just enough to allow the plate to rotate.  If the main plate is undersize, the spring pressure from the points can move the main plate in the engine bosses and this can change the gap.  The crank's cam position can alternate which spring is dominant as the crank is turned...which changes the gap setting you just made, because the plate can move with loosened screws.  I like to shim the plate, so it can't move laterally in the engine bosses.  The shims I use are feeler gauge "fingers".  Now, when you rotate the plate, the 1.4 point gap doesn't change, and you can rotate the plate to a position where the light will come on as the F mark aligns with marker.  Lock all three screws of the main plate down tight and do a final check of both max gap on the highest point of the cam on the crank, and that the light comes on when the marks align. You can remove the shim now.  Next move on to the 2.3 point set.  Again rotate the points cam to make the points open their widest and adjust the gap.   Then rotate the crank for 2.3 F mark alignment.  The 2.3 points have their own sub plate, which is moved on top of the main plate, to get the light to illuminate as the marks align.  In most cases, you are now done with point timing.  If ever you loosen the 1.4 plate screws for any reason, you will need the shim for the plate so the plate will hold lateral position, particularly if you attempt to use a dynamic timing light. I've done both, and no longer use the Dynamic to set basic timing, only to verify that the advance is working properly.

If you "run out of range" on either point set, you'll need to pick another of the three engine bosses to place the shims, and start over from the beginning with the 1.4 points.  I have yet to develop a rule about which mount boss to shim.  I think I used the lower left, last time I did this.   Now I just insert shims where ever is the largest before loosening the three screw for the 1.4 plate, 'cause that's where it was needed last time I did the adjustment. No need to do the same work twice.

There is a FAQ entry about shimming the points plate.
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Offline PeWe

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Re: Ignition problems?
« Reply #7 on: September 24, 2014, 01:41:04 PM »
Inspiration to how to adjust points.  CB750 but it's the same stuff, right?
http://www.hondachopper.com/garage/carb_info/timing/Static_and_Strobe_Timing.pdf
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Offline crazyxxhondaxx

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Re: Ignition problems?
« Reply #8 on: September 24, 2014, 04:38:42 PM »
Thank you all for the replies :) I'll see if i cant give it a shot tonight, if not maybe tomorrow.
Hate to tell you this buddy, but you have to wear clothes to work. There's a law or something.

Offline crazyxxhondaxx

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Re: Ignition problems?
« Reply #9 on: September 30, 2014, 06:19:56 PM »
So my uncle and I came up with a theory, everything seems to indicate the points are good, so we were wondering if a bad coil could cause these sorts of problems?
Hate to tell you this buddy, but you have to wear clothes to work. There's a law or something.

Offline TwoTired

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Re: Ignition problems?
« Reply #10 on: September 30, 2014, 07:03:31 PM »
I've lost track of what "problem" you are trying to solve.  ???

The coils are just a bunch of wire wound in "coils" inside the cylinder.  Two wires in each coil with two ends for the primary and two ends for the secondary going to thew spark plugs.
None of these wires should have a connection to the outer case.  There must be a connection between each end of each coil/'s wire but not between the the internal coils.

The secondary winding has a typical resistance of about 15000 ohms, measure with and ohmmeter.  The primary winding has a resistance of about 4.5 to 5 Ohms.  Pertains to stock coils, which don't have easily replaceable wires.  So maybe you aren't telling us the entire situation and you don't have the stock coils. I dunno.  I can only go on what you tell me.
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