I just replaced the CDI unit with a spare that I had on hand (cheap $25 units from China)…Yesterday, the engine suddenly wouldn’t start…Putting a double-handle super starter against the spinner only resulted in backfiring – like the timing was way out of whack…While installing the new CDI, I discovered the ‘real’ problem…I’m using a 2s Lipo for ignition, and ran the output through a $20 CC 10amp BEC set at 5.4 volts…One wire on the input side and one on the output side had broken at the solder on the PC board!…I don’t think those tiny voltage reducers with tiny wires were meant for gassers…I reordered another spare CDI – this time an RCEXL for BPMR6F from Valleyview…Regarding CDIs and what kills them, is my understanding correct?
Vibration
Input voltage too high
Sparkplug cap not secured to plug
Anything else?
-Ken

Why don't you buy a voltage regulator?

The real answer to your question is in your own words "cheap". That word could have cost you a plane if it had failed in the air. The new CDI will tell you what voltage to use and if you insist on li-po's then use a good voltage regulator. Some of the new CDI can use 7.2. Older versions are 4.8 only. Dennis

Remember there are no free rides so you get exactly what you pay for .... buy cheap, expect cheap performance.

Karol

not for everything..
I could pay $7 for a simple 30cm original 26awg Futaba extension wire,
or I could get a 22awg, silicone insulated original futaba jacked extension wire for $1 from china..

same deal with electronic parts, such as a basic linear regulator. It is usually the brand name we are paying alot of extra money for.

you could pay $40 for a posh brand linear regulator, and get exactly the same thing for $10 or less..! Believe me, more often than not, they use the same basic components.

Just yesterday, I got a couple of small field balance chargers for $10 with extruded aluminum casing. I pulled the board inside to see that "made in china" PCB was carrying Samsung microcontroller and ICs.. It Balances my, better than FlightPower, Rhino LiPos at 4.200, 4.199, 4.200 Volts... what could I ask more? My $45 FlightPower balancer cant balance that good!!

Yeah you are right, no free rides, but I aint getting ripped off any time soon..

BTW, I forgot to mention - I recently had the same exact wierd behaviour from my RCexl ignition module. I simply talked with then sent it back to the retailer / wholesaler in china, Before I could go to the post office to post it, he immediately credited my account for me to get another one for free.

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