spark timing different to cam timing?

Hi weed
Taffy did some investigations into the timing thing a while back
He used the dead stop method and a deg wheel to get tdc and found the flywheel marks to out by about 8-9 deg (from memory).
He asked some other guys to check there bikes and a couple have found the same thing.
My engines in a couple of hundred bits all over the garage at the moment but when I do put it back together I'm going to check and report.
There are some threads on it - probably in electrical section.
Coops

popup said:

i borrowed a timing light yesterday to check the spark timing (which i have never done before).thinking that it must be close ,but i'll get it spot on.
well i shouldn't have checked,because its not even close.
just can't quite get my brain around it at the moment.
i know cam timing is correct.
when i look through the inspection hole on the stator cover with the timing light shining on the flywheel, the single mark on the stator would be about 8mm to the right of the right mark on the flywheel (which is suppose to be t.d.c).
it doesn't matter where i turn the stator left or right, it just changes the position of the 3 marks, being to the left of the inspection hole or to the right of the inspection hole, the stator mark always remains about 8mm to the right of right mark on the flywheel.
what the hell is going on,ant ideas.it shouldn't be like that should it?
bike seems to go alright,starting is a bit iffy,but that could be pilot jet.

..weed..

Click to expand...

Hello weed,

I have made some crude mapping of the 2000 Husaberg ignition timing.

You must have a dial back strobe with an inductive pickup. The one I use is a Craftsman model 21023. It is adjustable from 0 deg up to 65 deg. This permits you to measure the exact number of degrees of delay it takes to adjust the strobe to fire when the flywheel TDC mark is in the inspection window on the Husaberg.

On the Husaberg there are 2 flywheel pulse magnets and the single pole trigger pulse coil. It operation as the center of the gap between the 2 magnets on the flywheel passes the trailing edge of the trigger pulse coil lamination stack 40 crank shaft degrees before TDC wave form triggers the CDI timing circuit to time out. The CDI delays the spark for 25 crank shaft degrees starting and at idle firing the plug 15 degrees before TDC , but then gradually advances the spark 15 degrees more to a total of 30 degrees before TDC at ~ 3200 rpm.

In summary, it seems as if the the wave form as the center of the gap between the 2 magnets just passes the trailing edge of the lamination at 40 degrees before TDC triggers the CDI timing circuit . The timing circuit delays the spark for 25 degrees ( fires plug at 15 degrees BTDC) during starting and up to idle speed (1600 to 1800 rpm). Then from idle up to ~ 3250 rpm the circuit gradually reduces the delay an additional 15 degrees such at 3250 rpm the plug is firing at 30 degrees BTDC.

The SEM stator is adjustible on the 2000 Husaberg and is indexed at the SEM factory to enable correct adjustment to be Mechanically set to 40 crankshaft degrees before TDC.

I was alone during this test and could not manage a detailed mapping curve, but then your question was how to set the static timing so this should help.

The basic setting of the static timing is on page 17 (section 7B) of the owners manual.

I have attached it for you if you don't have it. You need Adobe acrobat reader to view it, free at www.adobe.com

Let us know how it turns out,

Joe

RE: Re: spark timing different to cam timing?

joe

are we missing a trick here but the revs haven't beren mentioned. the strobe tends to be all over the show at low revs so i rev my bike up and check it. maximum advance is what i'm looking for and then i track the strobe advance ****** back and forth until i get the stator and flywheel line to line up, then i check the timing on the strobe and half it. so if it says i'm out by 16d i know i need to change the stator by 8d to get the 16.

hope i got that right!

secondly, the engine turns clockwise as viewed from the right. the first line that comes around is at 10d BTDC and the second one ISSSSS TDC.

hope i've got that right.

confirm joe please?

it's just that weed said the left line...

regards

Taffy

Re: RE: Re: spark timing different to cam timing?

Taffy said:

joe

are we missing a trick here but the revs haven't beren mentioned. the strobe tends to be all over the show at low revs so i rev my bike up and check it. maximum advance is what i'm looking for and then i track the strobe advance ****** back and forth until i get the stator and flywheel line to line up, then i check the timing on the strobe and half it. so if it says i'm out by 16d i know i need to change the stator by 8d to get the 16.

hope i got that right!

secondly, the engine turns clockwise as viewed from the right. the first line that comes around is at 10d BTDC and the second one ISSSSS TDC.

hope i've got that right.

confirm joe please?

it's just that weed said the left line...

regards

Taffy

Click to expand...

Not Exactly taffy.

Since there isn't any factory TDC mark on the engine that I know of, you would have to position the piston at TDC and then mark the engine case and ignition cover with a mark that lines up with one of the 2 marks on the flywheel. Chose your poision! This just makes it easier for you to find TDC for future operations that require the piston to be at TDC. Just realign the flywheel to line up with the reference marks you made.
.............

The book says that the mark on the stator is to be aligned with the left mark on the flywheel, while the piston is at TDC, on the 400 and 501 kick start models.

The book says that the mark on the stator is to be aligned with the right mark on the flywheel, while the piston is at TDC, on the 600 and electric start models.

Its that easy.

Regards,

Joe

RE: Re: RE: Re: spark timing different to cam timing?

well i was once a mechanic for my living and all the manufactureres had two marks on the flywheel. the first as it came around would be about 10d BTDC and the second was always exactly TDC.

i've often laughed at the idea that my owner's handbook says "find tdc and then move the stator to the mark on the flywheel".

now is that the cart before the horse or what?

weed: the lines are all over the show IMHO and thee only time they settle is when revving the engine. but you will boil after a few minutes that's why you only want to do this once in your lifetime!

regards

taffy

can i bring this thread back to the forefront?

i have had two bikes in that were '02s. one was a FE650 andd the other a FX470. the 650 i strobed on my new TDC mark at 66BTDC. so thats high revs, strobe adjusted. 66BTDC. half that is 33 and plenty good enough. lineaweaver has talked of 32 to 36BTDC yet joe shows an old owners's manual and it would appear that 40BTDC is good for the older machines so where did dale get 32-36? why the 8d dicrepancy?

i have been saying that neither line represents TDC and joe's sheet confirms that.

anyway, the 650 has a high end race cam in it and it backfires like billyeo on a closed throttle at mid revs so a needle lift is being tested sometime. the strobe is absolutely everywhere! makes no sense at all.

then a week later we have the 470 whichis standard. strobes at 25d BTDC at full advance. tried adjusting it ahead and still it's 25d BTDC? bike runs beautifully, very little difference between the two in performance but but the 470 doesn't backfire at all whatsoever on the run down?

i just think that there is something that the leccy geeks should be able to get their heads around to sort this out?

we got over the 650s troubles by raising the tickover a tad. the 650 had a new IXU24 in it.

BTW, i have no backfir on my 400 yet my ignition timing is a bit all over the show?

regards

Taffy

Taffy said:

can i bring this thread back to the forefront?

i have had two bikes in that were '02s. one was a FE650 andd the other a FX470. the 650 i strobed on my new TDC mark at 66BTDC. so thats high revs, strobe adjusted. 66BTDC. half that is 33 and plenty good enough. lineaweaver has talked of 32 to 36BTDC yet joe shows an old owners's manual and it would appear that 40BTDC is good for the older machines so where did dale get 32-36? why the 8d dicrepancy?

i have been saying that neither line represents TDC and joe's sheet confirms that.

anyway, the 650 has a high end race cam in it and it backfires like billyeo on a closed throttle at mid revs so a needle lift is being tested sometime. the strobe is absolutely everywhere! makes no sense at all.

then a week later we have the 470 whichis standard. strobes at 25d BTDC at full advance. tried adjusting it ahead and still it's 25d BTDC? bike runs beautifully, very little difference between the two in performance but but the 470 doesn't backfire at all whatsoever on the run down?

i just think that there is something that the leccy geeks should be able to get their heads around to sort this out?

we got over the 650s troubles by raising the tickover a tad. the 650 had a new IXU24 in it.

BTW, i have no backfir on my 400 yet my ignition timing is a bit all over the show?

regards

Taffy

Click to expand...

Hi Taffy,

This could be to the fact that there are three different cdi boxes from the 400 to the 650, this could be the reason why, the 400 cdi advances earlier than the others, just an idea.

Regards

Sparks

i hear ya!

hear is a search i did. some interesting threads on the ignition system.

http://www.husaberg.org/index.php?name= ... 5&start=50

regards

Taffy