Author Topic: Thoughts on points replacement vs electronic ignition  (Read 19706 times)

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Offline Gordon

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Re: Thoughts on points replacement vs electronic ignition
« Reply #50 on: January 05, 2010, 08:59:53 AM »
I am not saying this is the case here but one difference between points and electronic ignition that can/will affect ease of starting, power, fuel mileage, etc can be the advance curve.  

With the mechanical setup we have old springs that may not provide the same advance curve as 30 years ago, worn pivot points that allow variable curves, "gummed up" moving parts that alter the curve and response rate outright and even more so across the temperature range, etc.  With an electronic system that controls the curve, these variables are  reduced/removed as factors.  Then we also have the likelihood that the curves are different.  Perhaps the Dyna retards the spark at idle just a bit more or less which results in a perceived increase in ease of starting.  Perhaps the Dyna  produces a slightly more optimized curve through the midrange resulting in an increase in mpg.  Perhaps...

Ken

The Dyna unit that most seem to be referring to in this thread is the Dyna-S, which uses the stock mechanical advance, so there's no change in the advance curve. 

Offline tlbranth

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Re: Thoughts on points replacement vs electronic ignition
« Reply #51 on: January 05, 2010, 09:15:30 AM »
Partsnmore has the diachi set for $38. or $6 for each set of points. I'm with most of the other responders in that I don't want electronics crapping out in the middle of nowhere. An observation I made early on with my 750 was that older points' rub block gets burnished and wears less than new ones. So with a hondaman ignition, after a while you're laughing.
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Offline Gordon

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Re: Thoughts on points replacement vs electronic ignition
« Reply #52 on: January 05, 2010, 09:23:48 AM »
I still just don't understand this worry about an electronic ignition failing while you're out on the road somewhere. ???  As someone has already pointed out, any part on your bike can fail, including the stock points and condensers.

If you can carry spare points and condensers to replace faulty points and condensers, then you can just as easily carry spare points and condensers to replace a faulty electronic ignition. 

Offline IHWillys

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Re: Thoughts on points replacement vs electronic ignition
« Reply #53 on: January 05, 2010, 09:24:24 AM »
I suppose that my various "...can... and ...perhaps..." could be updated to something along the lines of "should but doesn't" then.

Is there an electronic ignition for the SOHC4s that controls the timing curve?

Ken

Offline 754

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Re: Thoughts on points replacement vs electronic ignition
« Reply #54 on: January 05, 2010, 09:27:07 AM »
There is quite a difference between touring with several bikes, with everyone carrying cell phones & credit cards VS being by yourself with 500 bux or less in your pocket.

 Also being in the wilds of Idaho/Montana, bike shops are fewerand farther between..

 the bike I am riding, still starts up easily with 6volts, or less, if its around freezing or warmer..
 Gordon, on some of the Dynas are the coils changed to different ohms? will they work OK if you put points back in?
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Offline MRieck

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Re: Thoughts on points replacement vs electronic ignition
« Reply #55 on: January 05, 2010, 09:28:39 AM »
 If you have an engine with a good amount of compression the 2000 adjustable curves are nice as is the generous retard during starting
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Offline Gordon

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Re: Thoughts on points replacement vs electronic ignition
« Reply #56 on: January 05, 2010, 09:33:10 AM »
I suppose that my various "...can... and ...perhaps..." could be updated to something along the lines of "should but doesn't" then.

Is there an electronic ignition for the SOHC4s that controls the timing curve?

Ken

Yes, there are a few, but JB was looking for options/opinions on inexpensive alternatives because of the cost of quality replacement stock parts, so the Dyna-S, which is the least expensive alternative, is what most were referring to.  

Calling the Dyna-S an "electronic" ignition is sort of a misnomer, though, but one we tend to use often.  It's technically a "points-less" ignition, since it still uses the mechanical advance.  There are true electronic ignition units that replace all mechanical parts and allow for customizing the advance curve, but they tend to cost quite a bit more than the points-less type ignitions.    

Offline Gordon

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Re: Thoughts on points replacement vs electronic ignition
« Reply #57 on: January 05, 2010, 09:38:55 AM »

 Gordon, on some of the Dynas are the coils changed to different ohms? will they work OK if you put points back in?

I'm sure some people change to lower resistance coils for their own reasons, but at least for the Dyna-S it's not required.  Both of my bikes with the Dyna-S have 5ohm coils. 

Offline Spanner 1

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Re: Thoughts on points replacement vs electronic ignition
« Reply #58 on: January 05, 2010, 09:39:39 AM »
What put me off Dyna S was the statement that ' the static timing is set at max. advance mark as the magnetic trigger lags behind a few degrees as rpm increase ' or words very close to that....so who knows what the timing curve is, right  ?
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Offline IHWillys

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Re: Thoughts on points replacement vs electronic ignition
« Reply #59 on: January 05, 2010, 09:40:44 AM »
... It's technically a "points-less" ignition, since it still uses the mechanical advance....

Good, errrr, point on the nomenclature, "points-less" vs "electronic".

Ken

Offline Gordon

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Re: Thoughts on points replacement vs electronic ignition
« Reply #60 on: January 05, 2010, 09:55:34 AM »
What put me off Dyna S was the statement that ' the static timing is set at max. advance mark as the magnetic trigger lags behind a few degrees as rpm increase ' or words very close to that....so who knows what the timing curve is, right  ?

I'm sure if I were building a high-performance sohc4 I would care and would probably go with an ignition that allowed me to set the timing curve exactly how I wanted it, but until then the old "S" works great for me. 

It's entirely possible that there are drawbacks to using what I use.  I'm not contesting that in any way.  All I'm saying is that if there are drawbacks, they're not big enough for me to have noticed in the tens of thousands of miles I've racked up with this set-up, but the benefits have been very noticeable and are ongoing.

Everything is a trade-off in some way.  Everyone has to decide for themselves what they're willing to trade for what they want to get.  I have been very happy, on two separate occasions, to trade a little extra money up front for never having to set the points or timing on my most-used bikes again.  And after several years of use the extra up-front cost is paid back by not having to replace stock, worn out ignition parts. 

Offline Peters1983

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Re: Thoughts on points replacement vs electronic ignition
« Reply #61 on: January 05, 2010, 08:10:36 PM »
I'm a bit of a noob with these bikes but I have learned quiclkly since I have started rebuilding mine.

I bought some random replacement points at a swap meet in august 08 and was not impressed at all with construction(thinly stamped units).

I decided to shell out the cash for honda factory replacements(extremely well built and pretty heavy duty). I had a lot of trial and error teaching myself to set them correctly. once i did that and rebuilt the carbs  I have not had a problem since, it is still not tuned further than a good bench sync and proper timing but it runs ten fold better than before and I have put well over 2000 miles on it with out having to adjust the points, in short very worth the money.

my experience with honda car and bikes is that the factory did things really well production wise and if you look at a lot of the race cars built(most of my experience with honda) the 10 second drag cars and scca racers rely mostly on oem parts.

I have looked into dyna, boyer bradsen, and this one http://shop.honda4.nl/catalog/product_info.php?cPath=141_84&products_id=354 (i don't know a whole lot other than a member in the project forum was going to use it on a track bike) it is top on my list of full electronic setups but I am going to give the hondaman unit a try before I spend any more than what he charges as the results have been spot on from anyone that has used it.

What I think it comes down to is what you are comfortable with and what good feedback you can take from this thread to make your own decision.
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Offline dave500

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Re: Thoughts on points replacement vs electronic ignition
« Reply #62 on: January 05, 2010, 11:58:00 PM »
its getting a bit a like two stroke versus four stroke dirt bikes debate,there both good,and both have different ways of doing the same thing,754,i set up points static as well and make sure its all good,then i shine the timing light and sure enough,they are both out a little so i "finalize"them,jonesy is spot on with older parts not sold so not made as much and up goes the price,ihwillys,my boyer ignition has the advance built into the black box and is supossed to replicate the factory curve,as far as it topping out at the full advance mark thats what it does,you cant tinker with it though!and petes1983,,get a proper sync done or do it,,an accurate bench sync is enough to get you running, and doesnt cater for actual vacuum,(which is being synced)that changes between cylinders as the engine heats up,,youll hear and feel the bike running much better,,,out of interest i replaced the points in my 308 cubic inch holden v8 years ago 92 i think,with a hall effect ,these have a bosch dissy standard and a bosch hall effect conversion was available,,the rotor has metal windows and a finned alloy box triggers the coil,,i kept the old points and condesor setup up in the boot for fear of all the above mentioned hassles and they are still there,i drive this car everyday its my only car,,and while not a honda bike it runs so much better ,,and the timing stays the same!murphys law,,if i throw them out the car will stop late at night ,raining with a flat cell phone,no coins,dressed like a bum so cant flag down help ,no torch(flashlight),in a bad neighbourhood.
« Last Edit: January 06, 2010, 12:06:57 AM by dave500 »