Setting dual points and adjusting timing

[Bob_Fla]

I have a 1984 850 T5

Can someone direct me to posts for procedures on setting dual points and adjusting timing.

OK - Can someone suggest a manual that would show the procedure for setting dual points and adjusting timing?
Thanks
Bob

[wirespokes]

Bob - I've got manuals - Guzziology and Haynes - and still had difficulty setting the points and timing on the LM1000. I even researched it on the net.

The big thing to realize is the firing order.

The crank rotates clockwise - looking from the front.

The right side (sitting on the bike) fires first. I don't recall perfectly at the moment, but seem to recall the red wire going to the points from the right coil. (how to identify which points are which) There are wiring diagrams on the net - like probably Greg Bender's site. Or you could watch for which set of points closes at the right time.

The right side is marked with a D on the flywheel - Destra = Right.  S = Sinistra = Left

Now here's the tricky part - the left side doesn't fire (Top Dead Center - TDC) until 450* later. Rotate the engine a complete revolution back to the right side, then past it to the left side. it will now be on compression stroke.

The right side then is ready to fire 270* later - just rotate the engine clockwise to the right side cylinder and it's ready to fire.

Keeping all that straight, along with the distributor rotation can be confusing. But if you read up on it, with data from the manuals and this, you should be able to get it right. Took me forever to figure that out.

[Gliderjohn]

If I could only find an old distributor machine for cheap...would make the job much easier.
GliderJohn

[fotoguzzi]

This might be of interest


http://www.thisoldtractor.com/moto_guzzi_tonti_distributor_dual_points_plate_modification_so_you_can_time_both_cylinders_properly.html

[Bob_Fla]

Wirespokes - Thanks. Ill have to read it a few times but that is great information.

Photoguzzi - I read the  link. Is the modification necessary to set the points?

Thanks for your help.

[Bob_Fla]

Basic question - What is the best way to turn the engine for setting the points?

[Moto]

Basic question - What is the best way to turn the engine for setting the points?

Remove the alternator cover at the front of the engine (the alternator is on the front end of the crankshaft).

Remove both spark plugs to make the engine easy to turn over. Put the transmission in neutral.

Use an allen wrench in the rotor fixing bolt, turning it clockwise as you face the motor.

Moto

[pat80flh]

Remember to remove allen wrench before hitting starter button.

[Antietam Classic Cycle]

I read the  link. Is the modification necessary to set the points?

No, it is not always necessary to modify the points plate to get the timing correct on both cylinders. 

[bodine99]

Can't you do it with a dwell meter? red lead to neg post on coil ground blk. lead, spin engine on starter with plugs out adj. a/r block off 2nd set with a piece of card board. set dwell on both then fire engine and set timing with a strobe. does MG give the dwell angle in a shop manuel?

[wirespokes]

I didn't need to modify anything to set my points.

As for turning the engine over, I've always preferred selecting fifth gear and rotating the rear wheel.

[yogidozer]

I didn't need to modify anything to set my points.

As for turning the engine over, I've always preferred selecting fifth gear and rotating the rear wheel.

Yup, same way I set the valves. Pull the plugs first.

[antmanbee]

Can't you do it with a dwell meter? red lead to neg post on coil ground blk. lead, spin engine on starter with plugs out adj. a/r block off 2nd set with a piece of card board. set dwell on both then fire engine and set timing with a strobe. does MG give the dwell angle in a shop manuel?

I always used to do it with a dwell meter. 
Going from memory many years ago, I would set the point gap on one set to specs and then check what the dwell was.
My meter did not have a setting for a single cylinder but I don't think it mattered.
What is important is to make sure the dwell is the same as it is on the first set of points.
The bike ran better set this way and the gap on the second set of points is irrelevant as long as the dwell is the same.
Then set the timing and the relationship between the 2 sets of points for each cylinder.
After a few tanks of gas check all the settings because sometimes they will change as the points wear in.
Now set them again and they should stay perfect for a long time.

[bigbikerrick]

Guzzis are generally easy to work on, and very satisfying, except for that  POS dual point dizzy in a tonti frame!  I got tired of messing around with the points and trying to get the timing right on for both cylinders, just to have it change when the points wear a bit.
  I put a Dyna 3 in both my Lemans 1000, and cal II and have not looked back for a second!
Rick.

[acogoff]

Guzzis are generally easy to work on, and very satisfying, except for that  POS dual point dizzy in a tonti frame!  I got tired of messing around with the points and trying to get the timing right on for both cylinders, just to have it change when the points wear a bit.
  I put a Dyna 3 in both my Lemans 1000, and cal II and have not looked back for a second!
Rick.

If the timing keeps changing after your point are run in, then you have other problems,as in rough cam or bearing play. Just checked this most recent set of points in my T3 after 30,000 since installed and points are not burned and the timing is nuts on. What happens to work for me is to put a little moly grease directly on the cam once a year. half the size of a bb is plenty. The moly tends not to fling about as easily as say a lithium type.  Also when you are checking or setting the timing it is a good idea to hold some slight counter clockwise pressure on the cam itself to remove any play in the advance springs to cam assembly.

[Bob_Fla]

Thanks for all the info.
I found this link to the owners manual:

https://www.manualslib.com/manual/781759/Moto-Guzzi-850-T5.html?page=44#manual

Still talking greek to me but its the only procedure I have found.

[Cdn850T5NT]

My memory is that red is right cyl, green is left (R, L as seen astride the bike). Going by memory here - I disconnect both primary leads from their respective coil low tension side and rig a test lamp in turn for 1 versus the other. You are looking at the point where the points ÒPEN (not close) in reference to the flywheel marks (2 degrees BTDC) when the test lamp goes out. I agree that manually holding against the advance mechanism is gòod. I bar the engine over in 5th gear, plugs out. Then i run engine with timing light as a check.  Seems to me that cam chain slack is not good. Always bar engine over in correct rotational sense to try to mitigate against this slack issue.

[rjamesohio]

At the risk of rekindling the 'points versus Dyna' discussion again - for me, with any old big Guzzi with the dual points, I'm going Dyna every time. Every old Tonti frame bike I've had and ridden that started with dual points either had a Dyna already or I put one in.

And - like Rick - I never looked back. Set them and forget 'em!

Just my friendly two cents....

[Bob_Fla]

Just verifying.
If you go to a Dyna system you have to have the Dyna Distrubuter replacement AND Dyna Coils - Correct?

[John A]

The cylinder numbering used to confuse me until I realized they are numbered front to back and not left to right

[Antietam Classic Cycle]

Just verifying.
If you go to a Dyna system you have to have the Dyna Distrubuter replacement AND Dyna Coils - Correct?

You do not have to use the Dyna coils. The Dyna III just replaces the points plate assy., not the complete "distributor".

[bodine99]

I too would go with a Dyna-3 EI carry the points plate on trips as a back up

[wirespokes]

Bob - is this your first time setting points and timing? If that's the case, we'll need to define a few things. It's a difference between explaining all the details like TDC and how a coil ignition works or just specifics to Guzzis. I don't want to get into the deep explanation if that's not where you're at.

[Bob_Fla]

Wirespokes. This would be the first time setting points and timing on a Guzzi. I've set points before and have set timing on old cars (many years ago)

From what I am reading I will need a light to so set the points? The light will tell me when the points open?

And then is there a different light for the timing?

If this is correct, what equipment (lights) do I need?
Thanks

[Furbo]

Wirespokes. This would be the first time setting points and timing on a Guzzi. I've set points before and have set timing on old cars (many years ago)

From what I am reading I will need a light to so set the points? The light will tell me when the points open?

And then is there a different light for the timing?

If this is correct, what equipment (lights) do I need?
Thanks

Bob,

I prefer a simple multimeter vs a lite. You can make a STATIC timing lite with a spare bulb and some wire.

I've used the dual point dizzy's for years with no heartache. Checked points once a year. Set gap, set timing static, then set timing dynamically at 4k rpm with a timing lite on the full advanced mark.

[wirespokes]

Bob - then you shouldn't have any trouble being familiar with the basic process.

One set of points (I think the left side) is mounted on an independently adjustable plate. Set the right side gap, then adjust the mounting plate so they just start to open at the static flywheel D timing mark.

Then, either rotate the engine backwards to TDC left side (go beyond a little ways, and then come back), or go 450 degrees clockwise. That link you posted (the manual) was confusing on engine rotation. Engine rotation is stated as clockwise looking at it from the front.

Then set the left side gap. With the flywheel at the static S mark, set the left side to just start opening at that point. Without a light, you can use very thin paper - in the old days, guys would use the cellophane wrapper from a cigarette pack. Place it between the points and when it could be pulled free was the point where they were just opening. You could use a trouble light - one of those pens with a point and battery and a clip lead out the back When the connection was broken the light would go out. Or connect an Ohm meter (multimeter) to each side of the points and watch for when it reads infinite. No contact. You get the idea.

The important timing mark is really the full advance. You can set it statically (engine not running) or with a timing light. Mechanics will tell you the engine should be timed as advanced as possible before it starts pinging. They'll accelerate up a steep hill and if it pings, retard slightly and try again.

All of this can be done without fancy electronic equipment and the bike run very well. Meters and timing light are nice to have though. Having a feel for all this makes it much easier taking care of problems middle of nowhere, should that be necessary, where all the nice test equipment isn't available.

[Bob_Fla]

Im going to put everyone's information together and give it a try. Ill let you know how it goes

[Bob_Fla]

Let me know if this thinking is correct.

I can set the points using a feeler at the top of the lobe (seems general)

Then if i run a light for continuity through the points i can check the timing when the circuit breaks using the S  D  3 2 marks in the inspection hole.

Can the timing be adjusted like this?

Can the timing be adjusted without the engine running?
 
Thanks

[Cdn850T5NT]

The use of the test lamp across the contact breakers, first the right cyl then the left cyl, really only checks that left and right breaker points open at the same relative-to-TDC time. Adjust them so they open at the same BTDC timing. Then with engine running use the strobe light to set the zero advance point (2 degrees BTDC) and to check max advance (34 degrees... at 4000 rpm's). You should find that the strobe-indicated timing is exactly the same for right cyl versus left.

[Cdn850T5NT]

Point gap should be 0.014" - 0.017". Then you go to set the LHS set of points so that the left cyl points open at the same base timing as the right cyl points.  You slide the whole left set of points along - guided by the nibs evident in the included photo - to make this adjustment. Be careful to not overtighten the screws so as to strip them. Use a good-fitting slotted screwdriver too. I cannot stress enough that if you bar-over the engine backwards you need to go far enough back so that you only approach the point of point opening from the correct rotational sense to avert prbs associated with timing chain slack!