ignition timing on a K2F

[muskrat]

And by the third hole it would have been square!

[a10 gf]

Dear all,
this is my first post in this forum.

As I have read a lot of things over all 4 years now and got really helpful informations,
I would like to give something back.

A few words \ pictures in the intro section ?

And interesting work on the magneto, nice to see experimentation skills.

[BSAlien]

Puuuuh!!!

First of all,
I would like to say „Thank you!“ to everybody!

It is not so easy for me to read and understand everything at the first time.
Some of your postings, I had to read several times!
I will try to make a summery (please comment) for me and for all the others, who are interesting in this post.

Summery:

- You can adjust the timing with the eccentric screw, cause it is an easy way, if everything is mounted
- But, everything else should be fine and in good condition
- The eccentric screw is normally used, to set the optimum point of a bright spark / peak flux
  (camring in position to the armature / point of opening contacts in relation to the most efficient voltage for the
  spark plug).   
- If you move the eccentric screw, you will change the intensity of the spark
- For adjusting the timing, this method is suboptimal!!! 


Questions:

Is there anybody out there, who can tell us, how much the intensity will get lower, if the camring is moved out of its optimum position … may be for 2°?
Is it possible to find out the ideal position of the camring to the armature with home tools?


Cheers
Hubse

[groily]

As some of the good family of the forum might recall, I advocate slotting the three mounting holes in the K2F body.

You know what, I tried and failed to find that original post of yours Richard when thinking about Hubse's question.
Not only a great idea, but one I've done a few times too, as it makes life a fair bit easier on machines where you can get to all three mag fasteners without having to take the cover off and pull the gear or sprocket.

[kiwipom]

hi guys, has anyone thought of using an auto advance system in conjunction with a manual magneto? if the manual cable was left off and replaced with a simple adjuster on the mag instead, timing could be altered that way, cheers

[duTch]

 

Tsk Tsk Dutch, you didn't warm up properly; Three beers before the first hole would have steadied your hand.

Yea wanna bet I didn't-  where  d'yea think dutch courage comes from

 

And by the third hole it would have been square!

  ...ish...

 I think I have photographic evidence somewhere... not sure if that's a good thing,  but seems it worked out ok


 

[beezermacc]

hi guys, has anyone thought of using an auto advance system in conjunction with a manual magneto? if the manual cable was left off and replaced with a simple adjuster on the mag instead, timing could be altered that way, cheers

This is something I regularly recommend to customers as you get 'the best of both worlds'. Set the ignition timing by wedging the weights open on the ATD and leave the cable slack. This means that you have the facility to retard the timing a little bit to prevent pinking when you're pulling up a hill. When starting the bike you don't use the lever to retard the timing as the ATD has already taken care of that. With regard to using an adjuster in the cable housing you are still moving the cam ring relative to the armature, so, weakening the spark; but provided you are only moving the cam ring very slightly there's no problem with this.

[kiwipom]

hi Beezermacc, glad someone agrees i was waiting to get shot down.  I intend to do this with my `Thorspark`set up as to get the adjustment if needed you have to loosen the rotor with magnets on and turn it a bit so i am going to replace my standard magneto with a manual one, has anyone else done that? seems a bit easier than slotting the mag holes, cheers

[raindodger]

Hello, Gents.
             I've done the same as Kiwipom suggested on my A10.  The reason being that there was a manual mag in the boxes of bits, and I did install the auto advance unit.  I bored a small hole in the bottom of the 'mushroom' and fitted a spring, then with an adjusting screw and locknut, it's easy to get the timing spot on.  The bike has always been a first or second kick starter.
Regards.
Tim.

[kiwipom]

hi guys, great to hear that it works good raindodger, didn't quite understand the hole in mushroom bit could you explain in more detail with pic if possible, cheers 

[kiwipom]

hi guys, raindodger i have the original manual bits on the mag so i just need to fix a wire on to the plunger and attach it to a suitable adjuster, cheers 

[raindodger]

Hello, Kiwipom.
               Sorry, can't do pics, I'm a bit of a luddite when it comes to technology.  However, I'll try to describe what i did.  The part that I drilled is called the A/R plunger, there's a slot at one end for the cable and the 'mushroom' at the other which locates in a slot on the camring.  I drilled a small hole in the 'mushroom' end and fitted a small compression spring which I stuck in with grease, and protruded about 1/4".  The cable adjuster was removed and a long adjusting screw fitted in place with a lock nut.  I found, initially, that the adjusting screw would catch in the plunger slot, but a small washer cured that.  I set the camring to about half of it's travel and timed the engine in the usual way.  Then the timing was checked and found to be 5 degrees late, 1 and a half turns on the screw brought the timing spot on.  I'm a summer rider, I'm getting on a bit and don't like the cold, but in the 8 years since I rebuilt the old lady, she's been totally reliable and a joy to ride.
Best.
Tim.

[BSA_54A10]

hi guys, has anyone thought of using an auto advance system in conjunction with a manual magneto? if the manual cable was left off and replaced with a simple adjuster on the mag instead, timing could be altered that way, cheers

Robbo's A10 was fitted up like that but was  PIA, Musky should be familiar with that bike.
With the cost of manual end caps now days you could sell one and buy a new eletronic ignition and still have enough for a celebratory pint.

[JulianS]

The other issue with using a manual end housing is the wear usually found between cam ring and housing allowing some variation in points gap and timing.

[BSAlien]

....... I set the camring to about half of it's travel ....

Hello Tim,

I think, you should set the camring next to the maximum advanced position for a maximum spark.
Can anybody confirm this?

Please have a look at the pic. It shows a camring in a normal housing with the eccenter screw in its middle position.
The end of the cam is just near to the top of the housing.

Hope everybody understand, what I mean.

Cheers

Hubse