slant six trigger wheel on the cheap.

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pishta
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slant six trigger wheel on the cheap.

Post by pishta »

Ok guys, I got a project and need some input. I was originally going to notch the inside lip of a power steering crank pulley to be my 36-1 trigger wheel to stim my Ford EDIS-6 module. I was just going to mark off every 10 degrees and make a chop saw cut about 4mm deep at the lines for a simple trigger wheel. Then I read that the tooth ideally needs to be the width of the VR pickup element and that turns out to be .25 inch. After mulling over the idea, I think the pulley lip is going to be too thin at about 1/8 inch so I decided to do the same chop job on the balancer itself as it is much thicker and has a thickness of about 3/8 where the teeth will be cut. So my question is: The 10 degree spacing at the edge of the wheel will occupy ~ .608 inches and the VR sensor is .250 inches. Is it going to matter if the teeth are not square, ie the top land (crest oftooth) is shorter than the bottom land (trough of tooth)? __ll___ll___ll___ll....? My buddy has a CNC that can make quick work of this and the reason I chose the balacer is that it is exactly concentric, no run-out. Also is the best shape of the tooth square or a right triangle with the falling edge at 90 and the rising edge at a 45? Would be harder to make but heck, its a CNC, it can do anything!
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Fred
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Re: slant six trigger wheel on the cheap.

Post by Fred »

Best shape is like many OEMs and few aftermarket. See the 2008 R6 thread in users' rides for a photo of a good wheel. A good wheel has a shallower cut in the missing region to maintain consistent magnetic flux. A crappy wheel has a deep cut there, and has a timing error on the first tooth following missing. Post pic here to confirm you understand.
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pishta
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Re: slant six trigger wheel on the cheap.

Post by pishta »

Fred, looked for "R6 thread" in 2008 users rides but couldnt locate a pic of a trigger wheel, but did see that cool flying magnet trigger. So you are saying the missing tooth should be maybe 1/2 height of the other 35? Whats a good height? I heard minimum 2mm deep normal tooth with a .05mm VR gap. The Ford wheel I saw looked like a gear with sort of rounded off teeth? thought that was bad.

saw this style all over the net as the de facto x-2 wheel style: Image

then I saw this x-2 (?) one, different or just better (as you described?) ? Image
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Fred
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Re: slant six trigger wheel on the cheap.

Post by Fred »

second one is better ;-)

viewtopic.php?p=35231#p35231

Image
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DonTZ125
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Re: slant six trigger wheel on the cheap.

Post by DonTZ125 »

Fred wrote:second one is better ;-)
Why? (Not being smart-assed - honestly curious)
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Fred
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Re: slant six trigger wheel on the cheap.

Post by Fred »

See previous post in this thread.
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pishta
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Re: slant six trigger wheel on the cheap.

Post by pishta »

Got it, thanks. Off to the cnc!
DonTZ125
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Re: slant six trigger wheel on the cheap.

Post by DonTZ125 »

Fred wrote:See previous post in this thread.
A good wheel has a shallower cut in the missing region to maintain consistent magnetic flux. A crappy wheel has a deep cut there, and has a timing error on the first tooth following missing.
Gotcha!
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