Setting ignition timing on T500

[sbaugz]

I just got a powerdynamo electronic ignition for my T500. They tell me to set the piston at 24 degrees (3.4mm) BTDC. Can someone walk me thru this process? I assume I go to TDC and then turn rotor clockwise while looking from left side of bike until the piston falls 3.4mm? My other question is which cylinder do I set the ignition to? Is it right or left, or doesn't it matter?

Final question- where can I get a reasonably priced indicator tool for setting piston to the correct position of 3.4mm before top dead center?

Thanks.

[ja-moo]

I use a digital caliper for setting the piston height.

[sbaugz]

Great, thanks. I'm still looking for information on which way to turn the piston on my T 500, and also which cylinder to take the timing measurement on for the power dynamo

[Zunspec4]

Hello,

You need to set TDC (using a dial gauge if you have one). Turn the engine clockwise, if looking from the left, and count the dial gauge reading until you reach 3.4mm BTDC. Then place the rotor on the crank so that the mark on the rotor aligns with the red mark on the stator (which you have already secured with the allan bolts in the mid of there elongated slots). Tap the rotor ensure it is seating correctly and tighten the securing nut. It does not matter if the crank moves slightly when doing this as you are going to be repeating this procedure. Reset TDC and then turn the crank clockwise until the dial gauge reads 3.4mm BTDC. Check the rotor and stator marks and if they are not quite on, due to tightening the rotor nut, then move the stator until you have it spot on. That's the procedure for the race version ign. anyway. The PD fires every 180 degrees so you have a wasted spark when a piston is at BDC, saying that I always use the timing side piston as the reference as you can see the dial gauge and rotor at the same time.

Hope the road PD ign. works the same or that is a redundant post

Cheers Geoff

[sbaugz]

thanks for the information. I am pretty sure the road version works the same way, because my instructions from PD basically tell me to do what you described.
The thing that wasn't clear to me on the PD instructions, was which way to turn the rotor to get BTDC. Thank you for clarifying that clockwise from TDC, will get me BTDC. Still have to figure out what type of dial I will use. I might rig something up so that I can use my electronic caliper. Maybe take an old spark plug and drill a hole the size of the caliper rod thru it.

[Zunspec4]

I have it easy as I am using centre plug heads so the dial gauge kit screws directly though the plug hole and gives an accurate reading.

This is the kit I use:


With the std. head having an off-set plug the dial gauge would read at an angle and you will not get an accurate vertical reading. If the head is off you can use a gauge fitted to a magnetic stand and get an accurate vertical reading. Or use a degree disc to achieve the same result (3.4mm BTDC = 24degrees BTDC). I found this handy calculator on the web: http://www.torqsoft.net/piston-position.html (T500 Stroke 64mm, Rod length 136mm).

Cheers Geoff