Dual points vs. single point

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62trvler

Dual points vs. single point

#1

Post by 62trvler » Mon Jul 23, 2007 11:10 am

Post by 62trvler on Mar 26, 2007, 5:36am

I have a dual points set up and was told a single point setup will make the motor run more efficient. Aparently the motor is working against itself due to timing issues. Hence the reason they were only used a few years. Any suggestions?

Post by junker1 on Mar 26, 2007, 6:59am

JUST MORE TO HAVE TO WORK ON.THE STOCK MOTOR RUNS GREAT ON SINGLE POINTS.THEY REALIZED IT WAS NOT REALLY DOING MUCH AND CHANGED IT BACK.MY THOUGHTS FOR WHAT THERE WORTH.

Post by King on Mar 26, 2007, 1:09pm

62trvler

I’m with Junker on this one. Simpler is better. My preference would be to go with an electronic set-up such as the ones supplied by 45 Parts Depot or E Beyond. For less that $200 you can eliminate points forever. Check through the threads here on that subject for more info.

Good luck

King

Post by Cotten on Mar 26, 2007, 2:51pm

The dual-points single-fire circuitbreaker was the Factory's finest ignition, allowing the most accurate timing of both cylinders.

It was only discarded to accommodate an electric foot.

....Cotten

Post by 62trvler on Mar 26, 2007, 4:04pm

Thanks all, my builder replaced my dual with a single and stated that the front cyl would time but the rear would be out of time. One cyl would be advanced and one retarded so the motor is working against itself. Also would make my maint easier. He said I'll have to change my coil setup but not sure how to do it. I wonder if I'll have to change the harness? I get the old one back so I'll have to do some thinking..........I'm a newbie to this

Post by Cotten on Mar 26, 2007, 8:28pm

Let me guess: Your "builder" kept the old hardware, right?

....Cotten

Post by 108 on Mar 27, 2007, 2:34am

My '48 FL has a home built 6 volt dual-point with automatic advance (photos in the "Garage") I rode it 3-4 days a week and a 200 mile trip last summer with no problems. I made my own timeing marks for both cylinders on the edge of the belt primary engine pulley. If I think the points have changed , just pull off the cover and throw a timing light on it, one at a time. If the timeings still on the mark- you know the points gap is still right without even takeing the timer cover off. The biggest advantage I see so far is more dependable 1-kick hot starting because it never back fires through the carb because of the "waste spark" anymore. Also,the idle has a more defined rythm, like a newer Harley. And Cotton, any theory on altering the timeing on each cyl. in releation to each other on a dual point?

Post by Cotten on Mar 27, 2007, 1:59pm

108 asked:
" And Cotton, any theory on altering the timing on each cyl. in relation to each other on a dual point ?"
The whole idea of a dual-point single-fire ignition is to be able to time each cylinder independently, and therefore more precicely.
The effect upon the other cylinder is minimized

'Tis a pity that the Factory would not produce what you have for yourself! But then they even forgot to put a second timing mark on the flywheels for a thousand bikes or more. (Duh.)

A single point dead-spark ignition isn't bad, but a single-fire system will give an audibly better running motor. You can hear the difference at idle.

....Cotten

Post by 108 on Mar 28, 2007, 12:43am

Thanks Cotton, I should have elaborated on that "altering the timeing"question. When I was first testing this dual point timer I played around with setting one cyl. a few degrees earlier or later than the other but couldnt tell any improvement. I just wondered if anybody else had tried the same thing.

Post by 62trvler on Mar 28, 2007, 11:44am

Cotten, I asked for the old dual point back and he said he always gives back all the old parts so shouldn't be a problem. I have very good digital photo's of everything before I took it in.



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Re: Dual points vs. single point

#2

Post by 58flh » Mon Oct 01, 2012 1:03 pm

HEY GUYS!--Once you UNDERSTAND how to work with Duel-point Timers!--YOUR GOING to LOVE IT!--ITS HDs ORIGINAL SINGLEFIRE!(so to say). As stated you can VERY accurately TIME BOTH CYL.s!--& thers a BOOST in power & FUEL MILAGE!, The reason why singlepoints are the norm!--is your setting to Front jug & done!, but theres that wasted spark!--What kills me is guys are paying $300 for Single-fire IG. & they had it all along!--Those running duel-point Timers, You guys know & understand how to set-up a duel-point TIMER! For the others ,JUST READ ABOUT IT! ITS not rocket science,& the AHA moment hits you, you will time-up your sled in 15min.(done)!---ITS NOT HARD!---My buddy rides a BSA with duel-points, & I love tuning that bike!--Literaly a start by hand!--Great little 650, Duel-points & 2-carbs.-(Amals)--Each cyl. is tuned PRECISELY!---GOOD-LUCK--& Wheels-Up---RICHIE 8)

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