strobe timing by yourself

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zotz

zotz

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Just wondering if anyone out there has figured out any ingenious methods for strobing the timing on their bike without having to wait for the wife, kids, etc. to free up and give you a hand. I'm not fussy on locking the throttle on and running about like a lunatic.
 
Place on center stand on thick carpet, have time light with its own
battery on DS of bike. Do not use bike power as voltage swings-drops
can mess with some or most lights.
Get trigger plate set where is starts but bolts loose enough to
diddle and hold on rev up to time.
Start as normal, let warm up reasonable if not already, then
while in saddle, one hand on throttle, one holding light trigger,
rev up to say 5000 and when stable lean over with light and
see what it reads and how stable it reads.
As you get practiced can go from idle to hi rev's and watch
the timing change and speed and top out.
Commando's do not heat up unless under throttle even sitting
on carpet, idle cools them below walking speed travel.
Sustained hi throttle needs fans of course or cook oil, then engine.

If ya think you can trust a child or wife to understand the
attention called for in such delicate harsh ritual, very good
as so few do.

You must do the Commando stand dance at least once for
that scope of its famous behavior, place on nice cement
and rev up while standing aside. Commando's lead, you follow.
 
Put your Norton on the side stand (works as well on thick carpet as on hard rock floor), turn the front wheel all the way to the right side (the throttle to the tank), kneel down beside the primary case and use your right hand to twist the throtlle and left hand to strobe.
 
And then use your other hand to turn the timing plate of the points/e-ignition to the proper position while monitoring the strobe! :)
 
hehe yeah pin throttle open so you can work strobe and trigger plate
at once.
Bewary of bouncing much load on extended sidestand.

hobot
 
Trust me, Wait for a friend or the wife. Even on the side stand 5,000 rpm is a trick. With it only on the wheels and someone else twisting the throttle and reading rpm to you it's a lot safer. If you do plan to go the "do it yourself" route be careful. 8)
 
On a decent carpet-cushion, house and shop may vibrate but the Commando stays put.
You can pick any rpm on an ignition unit's time curve to dial it in.
5000 rpm is mostly a stress on people not a normal Commando.
Alas going by numbers, is often not as good as going by ear, then
strobe measure and mark where its happy.

strobe timing by yourself


hobot
 
Hmmm. Sounds like it would be handy to be an acrobat with gorilla length arms. Someone working the throttle still seems best for me. Thanks for the options.
 
Fortunately, it's a rather quick procedure (10 minutes if all goes well) and very few people will refuse to hold the throttle while you diddle. "Here.. crank this and hold the needle at 4". I've never been able to do it alone.
 
My bike likes to moon walk like MJ. I tie a rope around the front wheel and tie the other end to the car bumper, fence post or tree. Turn the wheel to the right, use the throttle with the left hand and strobe with the right hand while the bike is on center stand.
 
It would appear that only the Pazon & Boyer need to be checked at 5k for full advance, although the Sparx doesn't appear on the graph and it also needs 5K.
 
I had never thought about it until now but it's true that IF you know the curve, you could time it at any RPM. For example, say you have a pazon - you could time it at 2000 RPM and look for 24 degrees; or a Trispark and look for 22 etc. So using those curves you could essentially time the bike at any RPM that was convenient. Of course, there could be variations from unit to unit but I'd be surprised if it was enough to bother with. Heck, back in the day, much of the time they were just timed statically without anything bad ever happening.
 
MexicoMike said:
I had never thought about it until now but it's true that IF you know the curve, you could time it at any RPM. For example, say you have a pazon - you could time it at 2000 RPM and look for 24 degrees; or a Trispark and look for 22 etc. So using those curves you could essentially time the bike at any RPM that was convenient. Of course, there could be variations from unit to unit but I'd be surprised if it was enough to bother with. Heck, back in the day, much of the time they were just timed statically without anything bad ever happening.
Click to expand...

WIth the electronic stuff you shouldn't see any variations.
 
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... :)
 
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.
 
MexicoMike said:
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.
Click to expand...

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. said:
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.
Click to expand...

+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.
 
nortonspeed said:
+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.
Click to expand...

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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