Which is more reliable ... Points or Electronic Ignition for Airheads?

Which is more reliable ... Points or Electronic Ignition for Airheads?

Seems there's two camps ... one side insist BMW electronic ignition is super reliable, produces more power, hotter spark, best thing since sliced bread, etc. etc.

never mind Adv is sprinkled with tales of woe ... airhead stuck on side of road from dead electronic ignition stories. can we say ... Fun and Games getting back up?

but some folks go 200k+ miles with zero problems... how can this be?

as you probably can tell by now... I'm firmly in dinosaur points/condenser camp. yes points are more fiddly, but setup correctly little to no performance loss. but does need attention as rubbing block wears. 25k+ miles maintenance intervals doesn't seem too bad to me. if something does go wrong with a points system, 99% you will be back up quickly. spare points/condensers are cheap and take up little space.

common points of failure seems to follow stock 12v Bosch coils on airheads. if replaced with high performance Dyna 3 ohm coil (for points), spark then becomes hotter. easily equal to BMW stock electronic ignition's spark. amp draw will go up slightly from 2.5 to 4amp range. note normal operating current draw will remain the same as stock coil. unless conditions exists that requires more current.

Edit: an important option was left off the survey by mistake. Points with a booster .. which quite possibly is the best of both electronic/points.

here's a perfectly good BMW electronic ignition system yanked from my R80G/S in favor of a Beancan with points.



beancan with points

Strictly regarding reliability, points.

Fewer ways for them to go wrong.

That said, I don't use points on any of my vehicles. The performance improvement overides reliability for my needs.

I would agree with Jon-Lars on the reliability issue but for sheer lack of maintenance I like the electronic. I don't mind replacing parts at 100k+ miles after doing nothing till then. That said I do carry some spares.

For the past eight years, I've resurrected a few POS beemers (with stock, points ignition) from long, hard decades of storage. I've had one issue with points. One issue in eight years of multiple bikes is good enough for me to just leave it alone.

Not to say electronic is bad, but for me it wouldn't make any sense to mess with the good thing I've got going.

8 years is impressive!

My 78 100/7 still has it's original ignition setup fitted. The bikes covered over 200k. To be honest it's never been an issue up until the past few years. The quality of the condensers has gone down the pan and my last set of points have been badly burnt after only a few thousand miles. Fitting an old condensor has sorted out the sparking at the points.

Points are more fixable, but more prone to problems.

Electronic is more reliable, but less fixable.

If you just want to ride, go with electronic. But if you go places where its a long walk if you break down, and have the mechanical know how to tinker, go with points.

Cy,

You give five options for voting in the poll but I think you left one out. I like to keep the stock points but include an electronic box. This makes the points system an electronic system but uses the points as the timing part of the system. This also keeps the mechanical advance unit. So if (and there always is) a problem on the road the parts to convert back to the stock points and condenser are still on the bike, still in place, just require moving a couple of wires and the electronic box is by passed. You are back on the road in 5 mins.

I guess I could vote for the last option,
<label for="rb_optionnumber_5"><input name="optionnumber" value="5" id="rb_optionnumber_5" type="radio">BMW points & Condensers are junk. replace with aftermarket electronic ignition
I do think the quality of ignition parts is likely to decline until they are virtually no longer available.
</label>

arrrrggghhh.... flat forgot to include last option of ignition booster. which adds a solid state relay while retaining points as triggering device.

which may be the best compromise as Disston pointed out. one simply disconnects booster and go back to points. if ever there's a failure and/or suspected failure.

but let's examine what we are protecting points from by adding an ignition booster.

a normal coil draws about 2.5amps. then depending on rpm will draw about 2.2 to 1.2 amps. replacing stock coil with a high performance coil raises current draw to about 4amp. but actual current while running will stay the same assuming engine is running properly. coil will only use enough current to jump spark plug gap.

contact surface area on a set of Bosch points is relatively large resulting in a robust electrical switch that's capable of supporting a much larger load than the actual 4 amp or so delivered.

failure mode for points are normally from rubbing block wearing and/or from using a condenser with incorrect values. resulting in a badly burned set of points and/or gap closes.

actual condenser failures are rare, have never personally seen one. to test use a quality meter like Fluke 87V with capacitor test capability to measure micro farad.

so if you've got a set of points that's running great with almost no transfer of metal from top to bottom contacts of points. during tuneups replace points but leave the old condenser alone. stick the new condenser along with a spare set of points in your tool bag for spare parts.

if a set of points has run many, many miles and still looks like new with little to no arc damage. then you've got a condenser with correct values. some folks like me will carefully dab the tiniest amount of high temp lube on rubbing block. dress points, adjust gap and timing, then run for another 15k+ miles before checking again.

Bosch points quality has gone downhill. best quality points I've been able to find are genuine Bosch points part # 01 030 preferably from new old stock. look carefully for where points are made. pkg below was made in Spain.

For BMW Beancan with points ask for points for a 72 VW bug or most desirable a genuine tiger stripe set of points for high performance 009 Distributor. # 01 030 points with tiger stripe have stronger spring tension for higher RPM without bouncing. about $15 retail

condenser tests out fine at .197 micro farad

I'll vote with Disston on this: points using a points amplifier (Dyna Booster). It's not a "set it and forget it" system with zero maintenance-- you have to check and inspect the points at Major Service intervals and periodically adjust the gap as the rubbing block wears and check the timing but at least this keeps you aware of the system. If the Booster ever goes out you can easily convert back to points-only and get back home. Electronics is reliable but it tends to go quickly and with catastrophic finality.

I think most of us on here don't mind the minimal maintenance required by points, and it certainly is nice to be able to look at something and diagnose what's causing an ignition issue. Similarly, most of us have heard of or experienced electronic ignition failures.

That said, a fair number of points airheads experience issues relating to wear and misalignment of ignition components that aren't easily fixed - like worn mechanical advance units, or bent camshaft noses. This happened to me.

So I was researching electronic ignition units, and we should note that there are some major differences between units. Like how the advance is handled, whether it can be adjusted, where the pickup is mounted (crankshaft or camshaft), and what sort of pickup (hall / photo gate). I ended up ordering a Sachse ignition from Germany (similar to Silent Hektik, and Sachse makes Enduralast's ignitions) for several reasons.. first, it mounts on the crankshaft, so issues with the timing chain or camshaft nose won't affect timing, and it allows me to keep my points in place as a backup. Second, it is photo gate triggered, which seems desirable to be because I often hear of hall sensors failing, though that could just be because there are more hall sensors out there. Advance is handled electronically, and there are a bunch of curves to choose from.

I'll report back when I get it mounted up. But I should say that if I weren't having issues with my points, I wouldn't have bought it.

Crank mounted has many advantages and I like your idea of leaving the points in place, why didn't I think of that? I had a crank mounted system that did the advance electronically. This was a couple years ago and they were the new rage then (still haven't been around for Airheads that long). So I had two problems with the one I had (sorry I forget which brand this was). #1 was the construction was flimsy. I didn't have it long enough to experience problems tho because #2 is why I got rid of it. #2 the electronic advance was a tiny potentiometer with ten positions. The instructions said to start at something like 3 and advance the switch till you had the performance and driveability you wanted. With out pinging , of course. Boy, did I have fun with that switch. I was cranking it up more and more. I had a tight rebuilt engine (still have it). I was tearing down the neighborhood streets. I was waving at the neighborhood kids as I speed by. I was the incarnation of the Speed Racer on my R90/6. Then it started pinging. I couldn't turn it down far enough or fast enough.

I has bad hearing. I talk loud. I didn't get along with this thing that gave me feed back in tiny whispers until it started screaming at me. I just did not think it was for me. I actually think this is a good solution for riders that still have most of their hearing except for another thing, It is expensive. So even though I had the money back then when I owned this I got rid of it. I really don't think it's for most of us Old Guys. That's all.

I'm doing the same thing. I got an enduralast ignition and one of their blank-off plates for the hole where the beancan goes. Since the enduralast requires a 3 ohm coil (which I already had because I was using a points beancan) I can just bring my points can along on longer trips and swap it back in if there's any trouble - just connect one wire, give it a rough static timing and it'll get me home. The enduralast only has two ignition curves to choose from: one for single plug and one for dual plug should I ever choose to do so. I haven't gotten the chance to fire it up yet and get some miles on it, but I really like it in theory.

I like the Sachse on my R90/6, when fitting it, just check that there is enough clearance between the trigger and the outer timing cover, especially if you have a 450w alternator fitted as I think that the rotor might be a tad longer than stock, giving clearance issues, if there is an issue you will just have to relieve the timing cover a bit.

I have not used points on an airhead since 1978. Electronic is the way to go especially if you are running dual plugs.

I'm not sure it's really a reliability issue. we're talking about a system that was designed over 30 years ago, using 30 year old technology. I've had several Oilheads and K bikes that had major mileage and not one hall effect problem. The sting that comes on the airhead system is rebuild ability and price. I think a modern upgraded electronic ignition system should last for many many miles.

I converted my G/S to points after the bean can went. At the time the new electronic systems were just coming out. I went with points just on the pure fact I can change them on the side of the road, and points and condenser pack down small. I was on the fence for a long time about an updated bean can, and still would have no problem using one. Cost wise it was about the same (unless you have a points can about), with the dyna booster and coil. More of a personal preference, than a reliability issue for me.

I have both a 1976 R-90 with points and three other airheads with electric (1x 83 RS, 2x84 RT, RS) . I have had no trouble with any of them as far as ignition issues go. Perform normal Maintainance on them and they will perform for a long time.

Dave H
San Antonio, TX

I judge reliability by "can I fix it on the side of the road."

After having bad experiences with my Boyer, it seems much easier to just carry a spare set of points if the current one burns out :)

My definition is a bit different. Reliability to me is "how often do I have to fix it on the side of the road."

"Can I fix it on the side of the road" is 'repairability' (to me at least)

Electronic is much more reliable, but infinitely less repairable by my definition.

You are absolutely right AW. Now you have added another whole new level to the debate. And all with out really changing any bodies mind about which one is the right choice.

To me at least there is no "right" choice. All options are a compromise to some degree and the intended use of the bike as well as the rider's mechanical competence should be factored in when deciding which option is best for one's own circumstances. There are no absolutes in this case. I feel that what I have is the best option for me, but it all depends on what you'll be using the bike for and where.