How Do I Time This Thing?

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Nailhead
Posts: 47
Joined: Mon Jun 23, 2014 4:05 am

How Do I Time This Thing?

Post by Nailhead »

I'm entering late middle age, but I'm young enough to have JUST missed the points-&-condenser ignition era. I think the last time I messed with points ignition was on an Alfa or Fiat 600 sometime in the '80's, and I can't remember how to static time an engine after removal of the distributor (bean can).

The points have been set to a Clymer-specified .040, and the BC is reinstalled at the approximate angle it was when I removed it (according to an iPhone photo...).

What now?

I feel like a moron.
'07 KTM 990 Adventure, ''93 Ducati 900SS, 80 BMW R100 RS, '7? Benelli 650S
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SteveD
Posts: 4910
Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: How Do I Time This Thing?

Post by SteveD »

What's late middle age? I've gotta get that out of the way before I can put my mind to a motorcycle question! I wondering if I should be considering it too? ;)

There's a small tool that helps a bit.
Image

Duane. http://www.w6rec.com/duane/bmw/points/index.htm

Snowbum. http://bmwmotorcycletech.info/ignitionsingleplug.htm

Chris Harris.https://www.youtube.com/watch?v=HShbaC9ORSo
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Major Softie
Posts: 8900
Joined: Tue Aug 03, 2010 1:46 pm

Re: How Do I Time This Thing?

Post by Major Softie »

"Late Middle-Age" missed points and condensor? DAMN, I'm ancient!
MS - out
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: How Do I Time This Thing?

Post by chasbmw »

Always use a Dooby paper to check when points are opening, smoke it afterwards!
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
pat76r90
Posts: 38
Joined: Wed Jul 10, 2013 6:11 pm

Re: How Do I Time This Thing?

Post by pat76r90 »

ZigZag or Tops? They're different thicknesses.
barryh
Posts: 730
Joined: Fri Oct 01, 2010 12:30 pm

Re: How Do I Time This Thing?

Post by barryh »

If you set the points gap with the bean can removed that was a smart move as it's much easier.
If you set the gap with the outrigger bearing plate removed you'll find the gap changes when you put it back on.
Points gap is .4 to .5mm or 16 to 20 thou. It's not hyper critical but you do have to get the decimal point in the right place. I'm too old for this metric nonsense and it confuses me so I work with thous.

With the can back on the bike, plugs out, rotate the engine slowly with an Allen key in the rotor bolt until you see the S mark in the timing window just opposite the chiseled timing mark on the side of the window. With this alignment the points should just be opening which you can check with what ever method is preferred - fag paper, test light or my preference a buzzer so I can hear the buzzer go off while concentrating on looking at the timing marks.
In the pic you can just about see that my chisel mark is a little below half way down the window so that's why the S mark is also a little below. The actual timing mark on the flywheel is not the S but the adjacent dot or drilling that I've filled with white paint. You can also just about see the TDC make which is the Line at the top of the window. Above that is stamped OT. When doing static timing you are rotating the flywheel towards you so full advance comes into the window first followed by the S and then OT. The exact look of timing marks varies between models so yours might not be exactly the same as in the pic.

It's a good idea to then check full advance with a strobe light but mine is always spot on so I routinely only bother with the static timing.

Image
barry
Cheshire
England
Nailhead
Posts: 47
Joined: Mon Jun 23, 2014 4:05 am

Re: How Do I Time This Thing?

Post by Nailhead »

Thank you very much!

I think I gapped those points with the bearing carrier on, but I'm going to double check it.
'07 KTM 990 Adventure, ''93 Ducati 900SS, 80 BMW R100 RS, '7? Benelli 650S
Nailhead
Posts: 47
Joined: Mon Jun 23, 2014 4:05 am

Re: How Do I Time This Thing?

Post by Nailhead »

Points regapped (they were way too loose, so I must have gapped them with the bearing carrier off), static timed per instructions using the beep on my Fluke meter. I didn't have the key handy, so I wasn't able to start it & check running.

I just have to scare up a timing light (haven't seen one for years), start It, and we'll see how it goes.
'07 KTM 990 Adventure, ''93 Ducati 900SS, 80 BMW R100 RS, '7? Benelli 650S
barryh
Posts: 730
Joined: Fri Oct 01, 2010 12:30 pm

Re: How Do I Time This Thing?

Post by barryh »

Unless the advance mechanism is worn there is no reason to believe the timing will necessarily be wildly out at full advance so I'd be happy to ride it until you can check with a timing light. Just listen out for any pinging as the engine approaches 3000 RPM under load.
barry
Cheshire
England
Nailhead
Posts: 47
Joined: Mon Jun 23, 2014 4:05 am

Re: How Do I Time This Thing?

Post by Nailhead »

Thanks Barry.

One thing I noticed that's troubling me is the position of the bean can now: it's at the limit of its CCW adjustment travel, whereas when I pulled it initially it was at 3/4 CW travel, and the bike seemed to run fine.

I would like to complete the timing process at this point because it's a PITA to remove the lowers on this bike. About a fistful of little Philips screws.

I just might take your advice, though-- it would justify running without the lowers for a while. I never thought it would look good as it does without them.
'07 KTM 990 Adventure, ''93 Ducati 900SS, 80 BMW R100 RS, '7? Benelli 650S
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