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TwiZ
11-06-2015, 04:14 PM
Copy and paste from my post in new members....Ok,like i stated in my last post the heating of cdi suzuki quadrunner worked,temporarily.Went to start it and wouldnt hit a lick.So,i wired in the Lifan CDI,and whalla,fired right up,BUT,when trying to rev the engine it pops thru carb,idles ok with a slight "miss"to it.Starts real easy and idles ok but like i said it will start poppin thru carb.Timing comes to mind for advance,or the pickup coil may not be sending a proper signal.Tried a brand new coil and did the same. The lifan pickup coil (thinking maybe not getting the signal range it needs)is cheap enuff and easy enuff to swap so im gonna try one,and in the meantime im thinking of slightly elongating the mounting holes on the pickup coil to give me some back and forth movement(scribe the original placement first) to see if that changes anything. I have looked everywhere for the readings the p.u coil should be sending and cant find anything and output numbers to the primary on coil to see if there is any differences between the lifan and suzuki. Also im going to monkey with a 4 prong chebby module and a duraspark ign. Was also wondering if a capacitor on + side of coil would bump up input. I just cant figure what would be the deal,seems like if it starts n runs it should be good to go,or it wont run,period.Any input would be helpful,thanks...p.s.,got the battery and led lights and regulator/rectifier working on the 200x,and it works beautifully!!! Nice to be able to finally see good at night

TwiZ
11-06-2015, 04:46 PM
Pickup coil output reading i got while running is 2.5 to 3.2 and ac stator voltage 70-75v

mendoAu
11-06-2015, 08:56 PM
Not sure what the question is but.......a cdi is made with a power curve. Meaning that it has a spark advance curve within the unit. It's basic purpose is to bybass the old points type distributor unit. So without knowing what specs them darn china units have built into them the spark advance is unknown. After rebuilding a couple of 440 dodge engines I know that spark advance has allot to do with performance. A cdi is not really simple. BUT it is just a capacitor that very quickly stores a certain amount of energy and allows the stator to tell it when to release that energy into the coil. The coil then quickly inverts that message to deliver about 10000 volts to the sparkplug. I'm happy with the cheap cdi I retrofitted into my 200es and saved me a ton of money but am still trying to locate info to find specific info as to what built-in advance certain cdi's are built into them. Thay can all be wired/retro'd into any unit but I'm sure/kinda that some are better suited to specific units. Any Dodge power wagon owners out there that want to comment on electronics? And what's with that righthand lefthand lug nut thing?HA!

Edit: also just my thinking but if the cdi has an internal sensor to advance the timing/signal it won't change that internal timing with changing the stator "timing".

TwiZ
11-06-2015, 11:27 PM
Kinda what i was askin is if the cdi cud be causing the poppin thru the carb when revvin it. I figured since they use this on a 150 cc lifan pit bike and another china 200cc bike i cant remember the name of. I kinda did the same thing with my 75 cj5 that you did with your dodge. I used the rotor,dist cap,dist base and t.f.i.coil from a 80s somthin ford 460, and a chevy 4 prong module to replace the duraspark ign box on that old AMC 360'and boy did it wake it up. It gave it a bigger diamiter dist cap which cut out cross firing the old amc small caps were noted for at higher rpms. The tfi coil is 50% hotter than the old can style coils. Had to widen the gaps on the plugs. So that made me think of using a duraspark box or 4 prong module on the suzsuki,and was lookin around and seen its been done with success. So im gonna monkey with that on the quad since i have these layin around. Just pains me to think of payin over $300 for a cdi for that machine when there is a possibility i can use cheaper more readily available parts. Now, would you know how to change the stator from a floating ground to a earth ground?That would open me up to many other cdi units,along with changin the cdi over to a dc unit,(thats easy)that would make even more options

TwiZ
11-06-2015, 11:32 PM
Oh and was wondering if a adjustable cdi would possibly address the timing curve issue i suspect and you mentioned

mendoAu
11-07-2015, 12:51 AM
Now that would be sweet....an adjustable cdi.!!!!!! Let me know if you locate any info on the chinese cdi's re: timing advance, etc. But since ya can't just change a spring like in a distributor I doubt much success.

TwiZ
11-07-2015, 02:55 AM
Ive been diggin since my last post. I just saw where the lifans have a adjustable stator/pickup you can get for them,thus makin me think it cant hurt to see if i can make mine somewhat adjustable. I watched vids of the adjustable cdi and they turn that knob and it would start sounding like mine. Im thinkin the cdi cud be set up for its advance according to diameter of flywheel,stroke ect,so if they arent the same then timing be different.idk, im just thinkin alot,but im determined to make this work. Even found a site on how to make your own cdi,and actually seems pretty simple,and all it requires is alt voltage and a trigger coil...things that make me go hmmmm