HPI ignition

[rough rider]

I was wondering if anyone has used the HPI ignition that DC Plastics sells and what timing did you use? This going on a combat wombat (modified). Thank you.

[dirty_rat]

I haven't used the HPI ignition, but I would probably set ignition timing to the latest specs put out by Hodaka for CDI ignitions, which for the Combat Wombat was 2.4mm or 0.094" BTDC or for the Super Combat which was 2.5mm or 0.098" BTDC.

[rough rider]

Hey Dirty Rat, nice to hear from you. The instructions state to set it at 2mm BTDC Max at 4mm BTDC, so the stock 2.4mm sounds about right. Hope this unit works as well as the PVLs did.

[viclioce]

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[ossa95d]

Victor, I think I should point out that your decimal points are off. I'm sure it was simply a typo. It should be 2.4mm which equals 0.094 inches. ".24mm" is nearly top dead center, and "0.94 inches" is nearly a full inch of stroke before top dead center. That would have the plug firing halfway through the compression stroke (about 90 degrees).

[viclioce]

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[Bullfrog]

It is often good to know whether or not the new ignition system has a built-in advance/retard curve. Makes a difference.

[Dale]

For the Combat Wombat, the Library says:

23 degrees or (.2.4mm or 0.94”) BTDC Shouldn’t matter which kind of ignition system it has, it should still fire at the same setting. I would set it there. JMHO... Victor

This advice concerns me... The model 98 Super Rat spec sheet states setting it's electronic ignition to .156 or 3.95mm. Should I be setting mine to these specs? Well, only if I want to hole my piston. I would suggest that before offering opinions on things as critical as timing that one should have first hand experience with the specific model and product.