Kicking back problems with my 72 Roadster

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Thomasdunstall

Thomasdunstall

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Hi everybody,

I've a kick starting problem with my 72 Roadster,
the bike start on the first kick and run really well
but it kick back to me...and I found it very unpleasent... ;)
I'm not talking about sporadic kicking back at you...it bites hard! And too often...

I have a last generation Boyer
do you think I can solve by retarding the timing until it just stops doing that?
Please advice

Some more info
the engine has been fully rebuilt, barrels rebored with new pistons and rings
0 mileage from restoration, great compression...

Mario
 
It doesn't cost anything so could not hurt to retard the timing by rotating the timing plate slightly anti clockwise just to see if it improves the situation.
 
Why the battery?
Click to expand...

because older Boyers like yours need the battery to be kept fully charged up, is it?

kick back is caused by either too tentative of a kicking prod or too advanced timing

so, if your battery is charged up and you are giving it good mighty kicks then if it still kicks back I would retard the timing a couple of degrees per the previous post's instruction

by even so, why would the timing change on its own if it has?

maybe the boyer plate securing little bolts inside the points cover are loose?

do you have a timing light and know how to stobe your timing to check it?
 
As stated above black sheep black box ancient analog boyah needs over 10.5 V or going brain bonkers advancing spark and if a Combat setting to the 32' per instruction can back fire to hurt ya till creep down retard till just don't bite back then can put light on and see where it lands with the iffy factory dial, known to be a handful of degrees off now and then. Its also possible the trigger wires breaking down, if not soon if enough will until upgraded terminals and finer wire leads. I had stalling out problems after a couple min idle fine on a tiny shirt pocket size 1.2 ah battery as 1000 rpm idle is not enough charging even on 3 phase 210 watt sparx to keep up voltage. Once this boyah dialed in and wires attended to - it may last a few generations.
 
1up3down said:
Why the battery?
Click to expand...

because older Boyers like yours need the battery to be kept fully charged up, is it?

kick back is caused by either too tentative of a kicking prod or too advanced timing

so, if your battery is charged up and you are giving it good mighty kicks then if it still kicks back I would retard the timing a couple of degrees per the previous post's instruction

by even so, why would the timing change on its own if it has?

maybe the boyer plate securing little bolts inside the points cover are loose?

do you have a timing light and know how to stobe your timing to check it?
Click to expand...

The battery is new and fully charged up,
boyer plate is safe in position
No idea of how to check with strobe
 
hobot said:
As stated above black sheep black box ancient analog boyah needs over 10.5 V or going brain bonkers advancing spark and if a Combat setting to the 32' per instruction can back fire to hurt ya till creep down retard till just don't bite back then can put light on and see where it lands with the iffy factory dial, known to be a handful of degrees off now and then. Its also possible the trigger wires breaking down, if not soon if enough will until upgraded terminals and finer wire leads. I had stalling out problems after a couple min idle fine on a tiny shirt pocket size 1.2 ah battery as 1000 rpm idle is not enough charging even on 3 phase 210 watt sparx to keep up voltage. Once this boyah dialed in and wires attended to - it may last a few generations.
Click to expand...

Ok hobot I'll try to retard a couple of degrees and see what happen till it don't bite back...
 
IF YOU HAVE A TIMING LIGHT WITH A PICK THAT WRAPS ROUND THE HT LEAD, THEN FOLLOW THESE STEPS.
remove the small plug from the primary cover. connect up the timing light to a good battery AND TO THE EITHER HT LEAD. Get the bike running then check the timing degrees inside that cover. Usually the timming mark should line up with 28 degrees when the engine is revved up fully according to your manual. Not going to tell you how high to rev it if you have not got a manual. [ please get one if you haven't.] Once you have established that the timing is 28 degrees, let the engine revs com down to about 1200 rpm to see if the timing retards from 28 degrees. [ the timing mark will appear to move to the front of the bike if it retards.] if you have more than 28 degrees on the std commando, then that could be your problem. otherwise if the timing does not retard when the revs drop down lower, that may be your problem.
let us know what you find
regards, Dereck
 
Thomasdunstall said:
Hi everybody,

I've a kick starting problem with my 72 Roadster,
the bike start on the first kick and run really well
but it kick back to me...and I found it very unpleasent
Mario
Click to expand...

Had the same problem with a Boyer. When timed correctly it would kick back. I swapped for a Trispark ignition which will not kick back as it goes to retard at low revs.

I believe there are a few manufacturers with this feature. Worth it if you do not want kick back, ever.
 
kerinorton said:
IF YOU HAVE A TIMING LIGHT WITH A PICK THAT WRAPS ROUND THE HT LEAD, THEN FOLLOW THESE STEPS.
remove the small plug from the primary cover. connect up the timing light to a good battery AND TO THE EITHER HT LEAD. Get the bike running then check the timing degrees inside that cover. Usually the timming mark should line up with 28 degrees when the engine is revved up fully according to your manual. Not going to tell you how high to rev it if you have not got a manual. [ please get one if you haven't.] Once you have established that the timing is 28 degrees, let the engine revs com down to about 1200 rpm to see if the timing retards from 28 degrees. [ the timing mark will appear to move to the front of the bike if it retards.] if you have more than 28 degrees on the std commando, then that could be your problem. otherwise if the timing does not retard when the revs drop down lower, that may be your problem.
let us know what you find
regards, Dereck
Click to expand...

Thanks Dereck no problem with tha manual...i have it! I know the correct rev to reach...
I don't have a timing light but I'm going to find one to check
 
Nortiboy said:
Thomasdunstall said:
Hi everybody,

I've a kick starting problem with my 72 Roadster,
the bike start on the first kick and run really well
but it kick back to me...and I found it very unpleasent
Mario
Click to expand...

Had the same problem with a Boyer. When timed correctly it would kick back. I swapped for a Trispark ignition which will not kick back as it goes to retard at low revs.

I believe there are a few manufacturers with this feature. Worth it if you do not want kick back, ever.
Click to expand...

Just finish a very expensive full rebuilding...can't afford more...
I need to find a solution with this setting...:(
I found that all the people here in the forum posted regarding kicking back problems had fitted boyer ignition...that's frustrating...
 
Thomasdunstall said:
I found that all the people here in the forum posted regarding kicking back problems had fitted boyer ignition...that's frustrating...
Click to expand...

Severe kickback problems from low battery voltage are usually associated with the older Boyer "Micro MkIII" ignition systems rather than the latest MkIV version, so which Boyer type is it that you have?
Are you sure that the ignition timing has been set accurately, as the degree scale inside the timing aperture of the primary cover can often be a few degrees out, so it is worth checking the accuracy of the scale with a degree disc.
 
L.A.B. said:
Thomasdunstall said:
I found that all the people here in the forum posted regarding kicking back problems had fitted boyer ignition...that's frustrating...
Click to expand...

Severe kickback problems from low battery voltage are usually associated with the older Boyer "Micro MkIII" ignition systems rather than the latest MkIV version, so which Boyer type is it that you have?
Are you sure that the ignition timing has been set accurately, as the degree scale inside the timing aperture of the primary cover can often be a few degrees out, so it is worth checking the accuracy of the scale with a degree disc.
Click to expand...

Hi Les,
The boyer is a MKIV late version, battery is ok
we set the timing with a degree disc, no timing light...
we have the same problem, with another commando with the same boyer...
start a little better than the Roadster but also has some unpleasent kick back...
Timing should be set at 31 BTDC at 5500 right?
But at 1000-1.200 the ignition should retard on 28 degrees, as Dereck said correct?
Do you think I can try to move the ignition plate anti clock a couple of degrees and check if it work?
 
Thomasdunstall said:
Do you think I can try to move the ignition plate anti clock a couple of degrees and check if it work?
Click to expand...

Why not try it (as recommended above multiple times)?
Easy to do, cannot hurt anything.

I was having similar problems with my PowerArc ignition.
Asked Fred at OldBritts if that (rotating disk couple of degrees) was a possible solution.
He said 'No".
I did it anyway.
Now much improved starting with little or no backfire or kickback.
 
Thomasdunstall said:
The boyer is a MKIV late version, battery is ok
we set the timing with a degree disc, no timing light...
Click to expand...

Do you actually mean the timing has not, as yet, been checked with a strobe? Because it isn't possible verify that the timing has been set accurately unless it is ultimately checked with a strobe as the advance curve often varies slightly between individual Boyer boxes.

Thomasdunstall said:
Timing should be set at 31 BTDC at 5500 right?
Click to expand...

Yes, the ignition should have reached the point of maximum advance by 5000-5500 RPM.

Thomasdunstall said:
But at 1000-1.200 the ignition should retard on 28 degrees, as Dereck said correct?
Click to expand...

(31 degrees BTDC for a Boyer) but at idle speed or just above, I would expect the firing point to be somewhere around 10 to 12 degrees BTDC, so the alternator rotor timing mark should be seen to be practically off the(left hand) end of the timing scale with a strobe at that speed?
If the timing doesn't appear to retard, then the two wires between the Boyer box and the Boyer stator plate (pickup) could be connected incorrectly (crossed over)?

You could use the advance x RPM figures given in the link below, as a guide, but as I mentioned, not all Boyer boxes advance at exactly the same rate.
http://www.nocnsw.org.au/technical/igni ... ando-boyer

Thomasdunstall said:
Do you think I can try to move the ignition plate anti clock a couple of degrees and check if it work?
Click to expand...

Yes, you can try that, but from what you have said so far, it seems that the timing may not have been set accurately yet.
 
Ok thanks Les
I can say yes, after we set the timing with the degree disc we didn't check with the timing light
so I have no for idea regarding the advance curve

so to be sure the timing is correct, I need a timing light and I have to check and follow the right advance curve, right?
What to do if checking the curve is not on 31 at 5000rpms? How to set proper timing than?
Do I have to move the plate anticlock a degree or two and check?
If set on 31 BTDC, retarding 1 degree I set it to 32? Am I right?
 
Thomasdunstall said:
I can say yes, after we set the timing with the degree disc we didn't check with the timing light
so I have no for idea regarding the advance curve so to be sure the timing is correct, I need a timing light and I have to check and follow the right advance, right?
Click to expand...

Yes, it really would be better to check with a strobe to verify it is set accurately before making any 'tuning' adjustments.
As this hasn't been done I'm guessing it is probably set too far advanced.
 
L.A.B. said:
Thomasdunstall said:
I can say yes, after we set the timing with the degree disc we didn't check with the timing light
so I have no for idea regarding the advance curve so to be sure the timing is correct, I need a timing light and I have to check and follow the right advance, right?
Click to expand...

Yes, it really would be better to check with a strobe to verify it is set accurately before making any 'tuning' adjustments.
As this hasn't been done I'm guessing it is probably set too far advanced.
Click to expand...

Thanks Les, I will also check for eventual crossed connection between the Boyer box and the Boyer stator plate
 
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