Does anyone know the recipe for humble pie?
After the disappointment with the CDI units when tested on one of my Jincheng Monkey bikes, I was left wondering why the POSH CDI module appeared to make such a difference when used on my Skyteam ST110-6 with a LIFAN 152FMH engine.
I wrongly assumed all Honda horizontal engine clones where the same but couldn't be more wrong: The magneto assembly and timing gear are totally different.
The Lifan engine has a far more sophisticated and powerful alternator-magneto and arrangements for varying the ignition timing electronically. The POSH CDI unit does advance the timing by a greater amount and a lot more quickly, as observed with my timing light.
This is a picture of the interior of the magneto housing. Unlike a normal monkey bike clone engine, the left hand crankcase cover is an integral part of the magneto. It carries the stator components, pulse coil, etc. It has to be accurately located to the main crankcase to ensure alignment with the rotor and its magnets, and for that purpose has two dowels that engage with holes in the crankcase. Watch out for these dowels dropping out and getting attracted by the powerful rotor magnets. They're only a loose push-fit in the cover.
The second picture shows the rotor with its firing and advance magnetic strip as described in my post on this thread:
http://www.chinariders.net/modules.p...ewtopic&t=8015
That the POSH CDI happens to work on this engine does not really invalidate the original premise. A huge variety of these devices are sold to be fitted to bikes with unsuitable engines with a promise of more power. They don't work on my Jincheng engines or on my Zongshen 125 cc engine either.