Points Timing

[Fux]

Ive never messed around with points before...

My Luna is slower than it should be. Iv`e been talking to a Sweedish fella who has a Luna with the exact same setup as me and his has quite a bit more power than mine.

I have done some tweeks to my carb and setup and it can now pull second gear in the hills.

The last thing for me to check is the Timing. I know it should have been the first thing to check but I have put it off simply because I havn`t done points before.

Armed with stickies book I will crack on.

One thing that I wonder about is that the Sweed is running 25 degrees BTDC and has done for a few years. I always thought that somewhere between 19-21 would have been better on a standard(ish) machine.

Basicly the 75 kit I am running is a true copy of a standard Vega cylinder.

Im I wrong?

[bristolmod]

I would say 25 BTDC is too advanced leading to overheating; "kicking back" and more serious problems.

Personally I would be looking at 20 BTDC as a max advance.

What is the fuel like over there? Same as UK- crap?

Chris

[Fux]

Yeah, same shitty stuff as the uk I think.

Ok, thanks i`ll start at 20. I have swapped mag-house, piston, cylinder and crank so timing should have been checked first...

I did fancy 12v but the points seem in good nic and its an easy starter (pluss the fact that the 12v casa kit costs £300)

[bristolmod]

I would start from scratch and ignore all marks on flywheel/ housing.

Basically determine TDC by using the positive stop method (arrow or mark flywheel, then rotate one way and mark on housing- then the other way and mark on housing. Divide the distance between the two which will give you TDC)

Then using a degree wheel rotate anti clockwise 20 degrees- thats where the points should fire.

Chris

[Fux]

Thanx...

And just to comfirm.. The fireing point is when the contact opens ? (the opposite of what I though )

[bristolmod]

the moment the points open- you can test this using a lamp and a battery, or do it the old way with a cigarette paper.

Not that familiar with the small frame Lambrettas- I assume the flywheel turns the same way as the larger scooters? (i.e. clockwise)

Chris

[Adam_Winstone]

If you've got a strobe then you should use this, just as you would with electronic ignition. If you don't have a strobe... buy one!

Adam

[Fux]

Err... A strobe I have!

I didn`t think they worked on 6v?

[Adam_Winstone]

Ignition is ignition and all you are trying to determine is when the plug fires. Providing the plug fires, it doesn't matter whether it is 6v or 12v. I strobe every 6V points system that I set up.

Incidentally, there is no difference between the voltage of the ignition of a 12V lighting system electronic stator or an original 6V GP200 Electronic stator, the LT coils are the same.

Adam

[Chris in Margate]

Definitely strobe. Personally I like the reassurance of knowing that I have seen the firing point and also that it is stable as I rev.
I did an electronic for somebody the other day and having rescribed a new TDC mark I lined up the pick up lines with the marks on the new flywheel and strobed it only to find they were about 3 degrees wrong. It was only a standard engine but I like to video repairs for the owners to show what has been done.
So strobe.