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Harley Davidson are wasted spark!?

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buddy
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PostPosted: 06:44 - 14 Jul 2022    Post subject: Harley Davidson are wasted spark!? Reply with quote

So I recently discovered that traditionally, harleys have wasted spark ignition.... Even though they're a vee engine, which apparently is why they have that lumpy tickover sound.

The thing is, surely they have completely different ignition timing on the front and rear cylinder. Believe it or not I can't find out if this is the case online. But surely it can't be, that's bloody insane, can anyone confirm this???
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arry
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PostPosted: 07:46 - 14 Jul 2022    Post subject: Reply with quote

https://youtu.be/XeuXShFIgyc

All explained in here, very entertainingly.
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A100man
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PostPosted: 11:09 - 14 Jul 2022    Post subject: Re: Harley Davidson are wasted spark!? Reply with quote

buddy wrote:
So I recently discovered that traditionally, harleys have wasted spark ignition.... Even though they're a vee engine, which apparently is why they have that lumpy tickover sound.

The thing is, surely they have completely different ignition timing on the front and rear cylinder. Believe it or not I can't find out if this is the case online. But surely it can't be, that's bloody insane, can anyone confirm this???


Interesting.. an insanity that became a virtue.. for some.
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Easy-X
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PostPosted: 12:02 - 14 Jul 2022    Post subject: Reply with quote

There's loads of wasted spark engines, an old Triumph T140 for example Wink

Makes sense when timing systems were simple but I'm guessing EFI Harleys keep the tradition.
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Polarbear
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PostPosted: 12:05 - 14 Jul 2022    Post subject: Reply with quote

arry wrote:
https://youtu.be/XeuXShFIgyc

All explained in here, very entertainingly.


How to justify the unjustifiable. Laughing But he did a good job trying. Thumbs Up
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buddy
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PostPosted: 13:07 - 14 Jul 2022    Post subject: Reply with quote

Easy-X wrote:
There's loads of wasted spark engines, an old Triumph T140 for example Wink

Makes sense when timing systems were simple but I'm guessing EFI Harleys keep the tradition.


Well there's no issue when it's an "inline" engine, as all the cylinders get the same ignition timing. But when it's a Vee engine it seems absolutely fucking crazy.
Harleys are what...45 degree vee? (Correct me is I'm wrong) So the timing is 45 degrees different on the front and rear cylinder.... I honestly can't believe they even run properly.
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arry
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PostPosted: 13:43 - 14 Jul 2022    Post subject: Reply with quote

buddy wrote:

Harleys are what...45 degree vee? (Correct me is I'm wrong) So the timing is 45 degrees different on the front and rear cylinder.... I honestly can't believe they even run properly.


Exact point of video:
https://youtu.be/XeuXShFIgyc?t=130
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buddy
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PostPosted: 15:01 - 14 Jul 2022    Post subject: Reply with quote

I eventually got to the bottom of this... The lobes on the points cam are offset, so the ignition timing is correct for the front and rear cylinder when they actually fire
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Old Thread Alert!

The last post was made 1 year, 286 days ago. Instead of replying here, would creating a new thread be more useful?
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