Topic: Sometimes runs all 4, sometimes just 2 PROBLEM FOUND

[Bailgang]

Other than a bad spark plug resistor and dirty connections I found a couple other problems which were spotted when the bike finally acted up while setting in my driveway. I found that no fuel was going to my #1 and 2 carbs which would explain the surging I felt the last time I rode it, why I'm not exactly sure because the petcock though it did have some sediment inside didn't seem that bad to stop the flow and none of the fuel lines going to the carbs were kinked in any way. I ended up draining the tank and remove the petcock so I could thoroughly clean it and after that it's been working fine. Problem #2 had to do with another broken wire, this one was the wire coming off the harness that leads to where the positive connection for the dyna hooks up (the connection that I repaired last week) except this time it was broken where I had originally soldered it 4 years ago at the point it ties into the harness, I had to unwrap half the harness to get to it.  . This was a wire supplied with the dyna kit which in my opinion is just a cheap grade wire, I solved that by replacing that wire with a thicker gauge higher quality wire. How that wire fit into the equation I'm not sure because if it had failed before it would've knocked out all 4 cyls not just 2. I found that out because all of a sudden it wouldn't fire at all, I checked for spark and had none on any cyl .......... and then out of the blue it did even though I didn't touch the harness.

Once all was taken care of I took the 550 out again and it ran fantastic never missing a beat ........ however that's what I said the last time when I repaired the first broken wire so with that in mind I'm not going to say it's fixed at least not yet. What I will say is that at this moment the 550 is running sweet and yes you guys can tell me "I told ya so" again. 

[BobbyR]

No I told you so. You went point by point and solved the problem. Once you own one of these bikes and figure their age related problem out, you get a great reliable bike. One more thing, it is your bike, you dod not buy something, you put in the hours and it becomes your bike over a period of time.

[Bailgang]

Nope, I regret to say it didn't fly this time either. On the way to work this morn it started acting up at about the same point it did the last time I rode it to work. What's driving me nuts is up to that point the bike was running perfect but as I was slowing down coming to an intersection that's when it acted up again, pretty much the same situation as it did the last time so I'm trying to see what the similarities are. I called into work for another vacation day (2nd one in 2 weeks  ) tried restarting with no luck then just let it set for about 10 mins, then it started up and took off for home and slightly stumbled a few times on the way back but never actually quit. This isn't making sense because the test ride I took the other day was longer than the ride this morn and it never missed a beat running flawless during that test ride. There were problems with the wiring that you would think would be sure fire explanations and the bike does actually run better since I fixed those issues but the problem still persists. I plan on doing a closer look at the fuel delivery focusing on the gas cap vent later today although opening the cap when it was in my driveway the other day still didn't convince the petcock to flow fuel, it was too dark this morn to say whether the carbs were starving for fuel but if nothing obvious whether it be electrical or fuel related shows up then the dyna is coming out and points plate going back in and see if the problem persists.

[bjatwood]

Don't give up on the vent issue, it can drive one to madness. (I know)

[Bailgang]

I searched this site and found a thread on how to remove the vent from the cap, I got it out and it was pretty cruddy so it's soaking overnight in some evaporust solution. Got to wait till Tuesday though for the new seal because the old one which wasn't that old tore on me when I tried taking it off.

[Vinhead1957]

Glad you are sticking to this riddle. Don't give up!

[kghost]

Have you tried swapping those cracked coils?

[Bailgang]

Have you tried swapping those cracked coils?

Not yet but it's on my to-do list.

[scottly]

if nothing obvious whether it be electrical or fuel related shows up then the dyna is coming out and points plate going back in and see if the problem persists.

After all the horror stories about intermittent dynas I've read in the last 3 years, I would try this first.   

[Bailgang]

After all the horror stories about intermittent dynas I've read in the last 3 years, I would try this first. 

I'd have to agree with that in fact swapping the points plate back in was the first thing I did initially but that's when all the other potential problems popped up especially the first broken wire I spotted leading to one of the modules which I thought for sure had to be the problem but then came the other broken wire, fuel starving and so on which have basically been giving the dyna a reprieve of sorts. It has been driving me crazy but in a way it's working to my favor because it's forcing me to take a closer look at things making me find problems I was unaware of and the bike is responding well to those fixes. Once I feel I've ruled everything out first and feel everything is doing what it's supposed to be doing but the problem remains then I'll swap the points back in along with factory 5ohm coils. The only prob with the 5ohm coils I have handy are the plug wires are a bit short so I'll need some splicers for that.

[Bailgang]

Well I regret to say that I just gave up, I never could get it to act up again while it was setting still and it was a toss up between the dyna and the cracked coils so I replaced the cracked 3ohm coils with a set of factory 5ohm coils and swapped out the dyna for points. I'm not ready to toss the dyna just yet, some day when I've got nothing better to do I swap the dyna into my 750 and see if the same problem pops up on it. After getting everything swapped on the 550 I took it out for yet another long ride, I even took the same route I take to work and it ran just fine with no hiccups what so ever ........ but I've already said that once or twice before haven't I?

[TwoTired]

Theory and technique:
Low ohm coils draw more current than the stock coils.  The electronic switch transistor gets warmer when it handles more current, and such devices can become intermittent in transition toward ceasing to operate at all.

A couple of troubleshooting techniques can help nail such an issue.  One is to reduce the current the switch has to handle.  With three ohm coils you can insert a 1 ohm resistor in the black power connection to the coils.  This will reduce the internal heat generated by the switch during operation as it will now have less current to pass.  You could also leave the points cover off for test runs, allowing the unit to get better cooling air flow.

Second, if you can get the unit to hard fail, spraying the transistor's containment box with cold spray (aerosol cans are available), can sometimes make faulty transistors return to operation until it heats up again.

[Bailgang]

I agree with you TT, some more diagnosing would've eventually revealed the problem but I simply lost patience. Fortunately this whole adventure was by no means a waste of time because in the process of of trying to pin point the problem I found a bunch of other issues with the bike that may or may not have contributed to the problem but I was totally oblivious to up to that point and the bike has responded well since I've made those repairs and those issues would've definitely had me pulling my hair out later on had I not spotted them now.

[BobbyR]

I think you have taken a very sensible approach. You had multiple problems, all of them needed attention. Since I am the victim of new Dyna engineering, I always default there. I have been reading what you have done and as you said, they could all be potential problems later.
Bravo and mission accomplished, the end point being a running bike. In time, you will probably continue to make small improvements as time and money permits.   

[neilc]

dyna s failure,i have a 28 year old RC Electronic I

[neilc]

I AM RUNNUNG A 28 YEAR OLD ELECTRONIC IGNITION,MADE BY RC ENGINEERING AND STILL RUNNING STONG,WHY CAQN'T THEY MAKE ONE WITH THE QUALITY THEY DID BACK THEN?SORRY ABOUT THE CAPS

[Bailgang]

I could've taken the 5ohm coils I have and hooked them up with the dyna but I tried that about a year ago when I first noticed the 3ohm coils were cracking. The bike ran just fine for about a mile down the road and the whole bike just died after blowing the main fuse, put another one in and it blew right away so I ended up pushing the bike back home and yes a 550 can be a real bear to push especially when the road has a very slight uphill grade. Once I got it home I cleaned all connections including the fuse block and tried again, that time it lasted 5 miles till it blew another main fuse. I'm not an electrical wiz by any means but I do grasp the basics and it made no sense to me why the 5ohm coils would draw so much to blow the main fuse even though they tested fine while the previous 3ohms had no problem, I would've assumed the 5ohm coils would've drawn less. I never could understand what or why it happened so back in went the 3ohm coils and all was well but being I never figured out why it happened made me very gun shy in trying to use the 5ohm coils again with the dyna when it started acting up again recently.

The 5ohm coils that are in it now are a different pair than the 5ohm coils I tried last year and so far the bike is just fine with them combined with the points and as long as it keeps running the way it is now I'm going to leave it that way ........ that is unless I get a good deal on an RC, pamco or boyer brandsen setup. Hey I can't help messing with stuff even when it isn't broke. 

[Honda550k]

Hey man sorry to hijack the thread but I too am going from dyna s to points plate. I'm just a little confused as the PO was the one that installed the Dyna. When installing the points plate do I use the same magnet shaft cover that goes over and covers the advance shaft or is there a different one required when using the points plate rather than the Dyna?

[Bailgang]

Hey man sorry to hijack the thread but I too am going from dyna s to points plate. I'm just a little confused as the PO was the one that installed the Dyna. When installing the points plate do I use the same magnet shaft cover that goes over and covers the advance shaft or is there a different one required when using the points plate rather than the Dyna?

That aluminum piece with the magnet has to go and a points cam put back in it's place. If you're lucky enough to find just the points cam then you need to make sure you install on the advancer correctly or else your spark will be 180 off. The points cam is usually sold with the advance unit so if you don't have a spare around you can pick one off ebay easy.

Just do what sweet_baby_james said in your other post.

[Spanner 1]

I'm always amused at the folks that fit Dynas or whatever just to torture themselves with trouble again and again, when the stock set-up is unbeatable. The even funnier thing is that folks trying ( in vain ) to fix their Dynas inadvertently end up fixing the original problem ( usually 40 yr. old neglected wiring connections ) which was why they tossed the stock points plate when they couldn't get the bike to run right.... one more thing, don't fit a Dyna without also replacing the regulator with an 'electronic' one as the stock reg. will supply too high a voltage to the electronics = crap-out... will happen on a long ride ( when the battery actually gets to full charge ) and the stock reg. allows the voltage to rise to maybe 15-16v before 'regulating' back to 14 or so volts....... common cause of Dyna failure, according to their biggest retailers, owners wrongly think it's heat related due to long ride.... anyway, just a cranky old gits opinion, but spend away , it's good for the economy...

[Bailgang]

Well the wiring problems had more to do with poor grade wire that dyna supplied with the kit but your comment about using an electronic RR is something that has made me always wonder because years ago I had a 70 Pontiac GP that I installed an HEI dist in and it was recommended that I switch the original external reg alt to the later internal reg alt. The way it was explained was that the later internal reg alt wasn't as erratic as the older external reg, the HEI would work with the older reg alt but for a long term basis it was suggested to use the later alt to make the HEI module happy and I always wondered if the same applied to our bikes. I have yet to have a charging issue with my 550 which is why I never messed with trying an electronic RR, it's one of those few occasion where I didn't mess with something that wasn't broke.

And like I said before I can't help messing with things even when they aren't broke which does make me a glutton for punishment at times but the things I learn along the way are invaluable and wouldn't have learned it any other way. My 550 is the first bike I've ever owned so I had a lot of learning to do but fortunately it's been able to endure all my messing around.