Shovelhead timing points doesn’t open

[HarmBMW]

Hello,

I’m doing a static timing on my 1973 shovelhead. I have set the gap of the points, set the intake valve down, set flywheel to advance mark line. Now I want to set the timing by moving the plate but it doesn’t hit the cam lobe.

What could cause the problem?

[JBinNC]

You set the advance timing (the timing mark in the hole) by turning the point cam ccw to the stop. The points should just open as the advance mechanism hits its full advance stop. There should be enough travel of the point plate allowed by its slots to correctly set the timing.

BUT, sometimes, with a non- stock cam, the slots in the point plate must be extended to allow for enough travel to set timing. If your bike was running well before, that is probably not your particular issue.

With the advance timing mark centered in the hole, and the point gap set properly, remove the condenser (let it hang by its wire) and grab the point cam with needle nose pliers or similar, and turn it full ccw. Adjust the position of the point plate so that the points just break when the point cam is fully advanced. A couple of tries should dial it in. A test light connected from point lead to ground will light up when the points break.

Don't leave the switch on too long as you work with it, the coil will get hot pretty quick.

Jim

[Dragstews]

Acu-time device tool locks advance mechanisms for accurate static timing.

Makes doing that job easy ....

.../// https://www.vtwinmfg.com/Instructions/16/16-0161.pdf \\\...

[HarmBMW]

I did it as the way in the PDF. But the narrow cam lobe doesn’t hit the points. The flyweights of the advance are open, that’s correct?) Can I adjust the lobes?

[JBinNC]

Hard to tell from your pic, but it looks like you have it advanced too far already. Retard the plate and advance it until the points open. If you don't have enough movement, you can file the slots with a chain saw file.

Jim

[Dragstews]

The cam lobe is clocked with the pin ... Isn't .. ??

And the advance unit is index to the cam .. ??

[HarmBMW]

I am at the front intake push rod goes up and then down again, then go to the vertical lign (73 shovelhead, that is correct isn't it?) and than the narrow lobe is somehow too much on top. It's almost vertically on top position, so the lobe can't hit the points, I can move the plate full retard or full advance without hitting the points.

The cam lobe on the advance unit is mounted correctly, the flat side of the cam is on the side with the pin of the advance unit.

What do you mean with "And the advance unit is index to the cam .. ??"?

I can file the slots with a chainsaw file, is that usually accepted?

[JBinNC]

The advance unit is keyed to a slot in the nose of the camshaft with a small pin. That pin could be sheared, and your advance unit is not quite in the right place on the camshaft. Worth your time to pull it and check.

Jim

[HarmBMW]

The advance unit was mounted correctly. I have tried to install my previous (worn) advance unit and ignition. With acu timer mounted now (When i install the acu timer, i turn it to open the flyweights, is that correct?) the points goes open at almost full advance.

But i want to install my new ignition, i saw the slots in the new plate are smaller..

But this small amount of play wasn’t before..

I’m thinking of file the slots larger, so my new advance unit and ignition can be installed instead of the old one.

[heyyodho]

Not sure if I follow correctly but it sounds to me that you could just take the new points and mount them onto your old mounting plate (with the longer slots).

[Guest]

I had this happen with those cheap points sets after I installed an EV27. Put blue streak points in it, they have a longer fibre pad runner that reaches the cam lobes much better

[JBinNC]

^^^+1 on the Blue Streak points.

I used the OEM Delco points for years, but the quality went to shit.

Jim

[Tattooo]

^^^+1 on the Blue Streak points.

I used the OEM Delco points for years, but the quality went to shit.

Jim

If you look on ebay you can find older Delco point sets....... I guess I have 20 sets of the older ones.....

[HarmBMW]

I have indeed bought a complete new ignition set. I have tried all new parts on old plate and vice versa but no difference..
Reading through the comments I have seen that the fibre pad of the new points is indeed shorter.. mess.

Question: I have attached a photo, isn't the small cam lobe to far on the right position? This position is on advance vertical line.
So, buying Blue Streak points will solve the problem, because they have a longer fibre pad?

[Guest]

assuming that the only issue is that your fibre block is too short on those cheap points and everything else is ok -
weights mechanism is fully functional and seated correctly in the cam, points cam is installed correctly and your retaining bolt is straight and tightened to spec, then yep the blue streak points should do the job. That was the only problem i had with mine after putting the new cam in and the longer fibre pad reached the cam much better.