Hi

I just finished a complete retoration of beta zero 1990.

I am having starting issues. I can get the motor to occasionally kick back, but cant get it to go.

I have a question re installation of stator and flywheel on this bike. I did not document exact mounting position of the stator when I took the motor apart.

The stator has 3 bolts and can be installed in 3 different positions if rotated around the crankshaft.

Do I need to worry in what position it is in terms of ignition timing?

Some pictures https://db.tt/9QXjpf67

Yes you need to worry - only one of the positions is correct.

The stator has a metal tip on one "corner"

Any best guess as to which way it was to point?

I am not familiar with a Beta Zero. If you set the piston at TDC and look on the flywheel where the ignition trigger is, then put the stator in the position that aligns (as near as possible) the pickup coil with the trigger.

Surely the LT wire will only reach the external connector when the stator is in the correct position?

also consider that the quality of the frame earthing for the motor casings and the HT coil may have been affected by your restoration

there is a small 2mm hole in the flywheel and on in the stator you need to put a pin in these holes to line them up at around 2mm btdc but this is only from memory so best check for the exact figure the holes will end up around the 4-5 o clock position

 

Normally there are the tell tale signs where the screws were originally mounted on the back plate so you can line it up to where it was before.

 

I presume because of the wire position in relation to the case you couldn't get the thing 1/3 rd out of rotation?

 

if in doubt try it in as many different positions as you can and see if it will start and run.

Paulc we used your method and it worked well. The bike is running, but it is very weak on power and its not easy to start. Once it gets going I get some flame out the tail pipe, and its just slugish

Can you tell me if we are retarted or advanced in timing?

just checked and the proper timing figure is 2.2-2.3mm btdc its hard to say if your timing is advanced without seeing the bike as it could also be carb related with those symptoms (weak mixture) to get the timing spot on you really need a dial gauge with an adapter for the plughole 

Thank you for the input. 

 

i am attaching 3 pictures of different mounting options for the stator. Can someone tell me which of the 3 ways it should go on?

 

I also have picture of the flywheel. I assume that I need to install flywheel with the key onto the crankshaft.

 

Thanks

for stator position, I just pulled my 1992 off (same set up) the quick key is that the metal wire harness retaining plate near the harness penetration point . the wire harness comes into the engine and comes up behind the retainer plate that holds the jacketed harness (fwd inbd of stator) and directs the wires into the stator. so where the wires go into the stator is @ 1-2 oclock position.

I know this is not technical only visual.

Edited August 6, 201511 yr by robertaccio

without looking this is what I recall, I can verify later when I look out in the garage. so trigger is down facing wires come out of stator @ 2 oclock, harness gets "clamped" behind steel harness retaining plate

Thanks for everyones help got the timing spot on!

Here is the video documenting the rebuild.

Bike runs like a top!!