strobe timing by yourself

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Re: strobe timing by yourself

Postby MexicoMike » Sun Jul 18, 2010 8:54 am

I just realized a major fallacy with my observation...to set it using the curve at any RPM you need to ACCURATELY know the engine's RPM. But the only handy "tool" to do that is the Commando's mounted Smith's Tachometer. Oh well... :)
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Re: strobe timing by yourself

Postby pvisseriii » Sun Jul 18, 2010 9:03 am

Ya know, waiting for the wife and kids is not a bad way to go. By inviting them in you can keep that "Family neglect" and "child abandenment " issue in check. Or at least seemingly so.
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Re: strobe timing by yourself

Postby L.A.B. » Sun Jul 18, 2010 9:31 am

MexicoMike wrote:I just realized a major fallacy with my observation...to set it using the curve at any RPM you need to ACCURATELY know the engine's RPM. But the only handy "tool" to do that is the Commando's mounted Smith's Tachometer.


I never worry about trying to set an electronic ignition at a particular RPM level, as any bike's revcounter is likely to be out by a certain amount, and the specified RPM level is not supposed to be a target RPM to set the ignition at, but an engine speed past where the ignition should have stopped advancing, as the Boyer instructions say: "..time with a stroboscope to 31 B.T.D.C. (28 DEC. with standard ignition) with the engine
running up to 5000 r.p.m."
that's running UP TO 5,000 RPM, not AT 5,000 RPM, so I just rev it past the point where the ignition stops advancing and set it so that it does not exceed the maximum advance figure. I know some electronic ignitions such as Boyer Bransden are supposed to keep on advancing even after 5,000 RPM, however this extra amount of advance must be small, as I've never actually noticed it happening when setting a Boyer ignition. http://www.boyerbransden.com/pdf/KIT000 ... 00017_.pdf

I've always strobed ignitions on my own, no problem.
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Re: strobe timing by yourself

Postby nortonspeed » Sun Jul 18, 2010 10:36 am

L.A.B. wrote:I never worry about trying to set an electronic ignition at a particular RPM level, as any bike's revcounter is likely to be out by a certain amount, and the specified RPM level is not supposed to be a target RPM to set the ignition at, but an engine speed past where the ignition should have stopped advancing, as the Boyer instructions say: "..time with a stroboscope to 31 B.T.D.C. (28 DEC. with standard ignition) with the engine
running up to 5000 r.p.m."
that's running UP TO 5,000 RPM, not AT 5,000 RPM, so I just rev it past the point where the ignition stops advancing and set it so that it does not exceed the maximum advance figure. I know some electronic ignitions such as Boyer Bransden are supposed to keep on advancing even after 5,000 RPM, however this extra amount of advance must be small, as I've never actually noticed it happening when setting a Boyer ignition. http://www.boyerbransden.com/pdf/KIT000 ... 00017_.pdf

I've always strobed ignitions on my own, no problem.


+1 Now we are talking sense, besides if you are to immobile to do this trick on your own you might consider to quit riding your bike for your own safety.
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Re: strobe timing by yourself

Postby L.A.B. » Sun Jul 18, 2010 11:12 am

nortonspeed wrote:+1 Now we are talking sense, besides if you are to immobile to do this trick on your own you might consider to quit riding your bike for your own safety.


Well... "Necessity", as they say, "is the mother of invention" and for those of us who live alone, and therefore may not always have the luxury of "an extra pair of hands" to call upon at various tricky workshop moments, a method often has to be devised so that a particular task can be accomplished without assistance.
But, as far as the strobing is concerned, my workshop has a wooden floor covered in thick rubber matting, I can rev the nuts off any bike on it's centre stand on that surface-including my Commando without it moving an inch.
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Re: strobe timing by yourself

Postby zotz » Sun Jul 18, 2010 12:34 pm

I should only have to set it around 5000 once and then see what it is at 2 or 3000 and use that figure from then on. Regardless I was just fishing to see if there where any genius methods out there for setting timing alone.
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Re: strobe timing by yourself

Postby Yellow_Cad » Sun Jul 18, 2010 1:43 pm

L.A.B. wrote:
MexicoMike wrote:I just realized a major fallacy with my observation...to set it using the curve at any RPM you need to ACCURATELY know the engine's RPM. But the only handy "tool" to do that is the Commando's mounted Smith's Tachometer.


I never worry about trying to set an electronic ignition at a particular RPM level, as any bike's revcounter is likely to be out by a certain amount, and the specified RPM level is not supposed to be a target RPM to set the ignition at, but an engine speed past where the ignition should have stopped advancing, as the Boyer instructions say: "..time with a stroboscope to 31 B.T.D.C. (28 DEC. with standard ignition) with the engine
running up to 5000 r.p.m."
that's running UP TO 5,000 RPM, not AT 5,000 RPM, so I just rev it past the point where the ignition stops advancing and set it so that it does not exceed the maximum advance figure. I know some electronic ignitions such as Boyer Bransden are supposed to keep on advancing even after 5,000 RPM, however this extra amount of advance must be small, as I've never actually noticed it happening when setting a Boyer ignition. http://www.boyerbransden.com/pdf/KIT000 ... 00017_.pdf

I've always strobed ignitions on my own, no problem.



L.A.B can you go a little further into your method of strobing alone such as approx. what rpm you do use and any bike handling methods that make it easier?
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Re: strobe timing by yourself

Postby norbsa48503 » Sun Jul 18, 2010 3:01 pm

The point is that you set it were it appears to land. As the strobe fools the eye into seeing that the mark has quit moving it must land on the correct for a Boyer’s 31 degrees. If you were to set it before it quit moving by using a lower RPM you would find that it is not set right at a higher RPM the 5000 is just to make sure it's not going any further advanced up at the point when appears to stop moving. If it did you could hole a piston on a long high speed run down the X-Way. I have made some nifty aluminum rotors for our older units, they can be seen on my site.
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Re: strobe timing by yourself

Postby hobot » Sun Jul 18, 2010 3:55 pm

My simplistic concept is just set it by hand trial error for no back fire
1 kick staring. That sets road bike max advance at what ever rpm, period end of story. Like oil gauges and compasses on handle bars, can put a strobe on it
to see where it lands, but no useful information to act on, just where
to mark lines for next time.
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Re: strobe timing by yourself

Postby britbike220 » Sun Jul 18, 2010 4:03 pm

A digital timing light makes the world a better place.

I think it's silly not to find a second person to help. Though timing can be done alone it is difficult, time consuming and the accuracy sometimes leaves a bit to be desired.
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Re: strobe timing by yourself

Postby zotz » Sun Jul 18, 2010 5:07 pm

MexicoMike wrote:I just realized a major fallacy with my observation...to set it using the curve at any RPM you need to ACCURATELY know the engine's RPM. But the only handy "tool" to do that is the Commando's mounted Smith's Tachometer. Oh well... :)


Not only the tach but the assumption that the marks on my Sparks rotor are accurate and that the curve on all Boyers are exactly the same. There's just too many variables to accept any of these values as absolutes.
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Re: strobe timing by yourself

Postby L.A.B. » Mon Jul 19, 2010 4:50 am

britbike220 wrote:I think it's silly not to find a second person to help. Though timing can be done alone it is difficult, time consuming and the accuracy sometimes leaves a bit to be desired.


Silly,

Difficult?

Time consuming?

Accuracy leaves a bit to be desired?

To do it alone, the right hand controls the throttle, and left operates the strobe, simply rev it past the point where the ignition stops advancing, and if the ignition setting is out then re-adjust it until it's right, as each check takes no longer than a few seconds and the pickup plate can be moved without stopping the engine, so I can't see how doing it this way is particularly silly, difficult, time consuming or inaccurate?

Revs went up to at least (a tach indicated) 5,000 RPM, but note that the bike is on its main stand, and it was not chocked, tied or otherwise restrained in any way.
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Re: strobe timing by yourself

Postby swooshdave » Mon Jul 19, 2010 8:53 am

L.A.B. wrote:Revs went up to at least (a tach indicated) 5,000 RPM, but note that the bike is on its main stand, and it was not chocked, tied or otherwise restrained in any way.


When you're leaned over looking the strobe do you just go until it won't advance anymore, thus achieving max advance and the point at which you need to adjust, if needed?

That works for all but the Boyer which according to the chart on the previous page, keeps advancing past 5k rpm.
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Re: strobe timing by yourself

Postby L.A.B. » Mon Jul 19, 2010 9:02 am

swooshdave wrote:
L.A.B. wrote:Revs went up to at least (a tach indicated) 5,000 RPM, but note that the bike is on its main stand, and it was not chocked, tied or otherwise restrained in any way.


When you're leaned over looking the strobe do you just go until it won't advance anymore, thus achieving max advance and the point at which you need to adjust, if needed?

That works for all but the Boyer which according to the chart on the previous page, keeps advancing past 5k rpm.



So who's not been paying attention? :mrgreen:

L.A.B. wrote:I never worry about trying to set an electronic ignition at a particular RPM level, as any bike's revcounter is likely to be out by a certain amount, and the specified RPM level is not supposed to be a target RPM to set the ignition at, but an engine speed past where the ignition should have stopped advancing, as the Boyer instructions say: "..time with a stroboscope to 31 B.T.D.C. (28 DEC. with standard ignition) with the engine
running up to 5000 r.p.m." that's running UP TO 5,000 RPM, not AT 5,000 RPM, so I just rev it past the point where the ignition stops advancing and set it so that it does not exceed the maximum advance figure. I know some electronic ignitions such as Boyer Bransden are supposed to keep on advancing even after 5,000 RPM, however this extra amount of advance must be small, as I've never actually noticed it happening when setting a Boyer ignition.
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Re: strobe timing by yourself

Postby grandpaul » Mon Jul 19, 2010 9:11 am

Yep, single person timing, 90% of the time for me.

Rev it up good, strobe it, adjust stator plate (if needed), rev it again and double-check.

Why make such a fuss?
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