Incompatible CDI

[tortoise2]

No affiliation, just an example of an incompatible installation . . 6-wire AC Blue Racing CDI installed in a DC system . . smokes it!

[90GTVert]

I left this comment for him since no one else has enlightened him to his error :

"Just FYI, you installed what appears to be a CDI intended for AC systems in place of a DC CDI. This is user error, not the fault of the seller or parts manufacturer unless it was labeled as a DC CDI. An easy way to tell you have a DC CDI is generally that the CDI is very large. Notice how much larger your stock CDI was compared to the aftermarket CDI. Stock AC CDIs are very close in size to the blue one.

I know you stated that you have been a tech for 20-25 years, but you have a bit to learn when it comes to Chinese bikes. No offense meant there. They can be difficult and many shops turn them away for reasons like this. Unless you have a good dealer around, you don't just look up a part like you would on say a Honda and expect that it is the right one. You have to know your scooter and may need to take measurements or count wires and things like that. One may have an AC CDI on a 150, the next may be DC. One will have an 8 pole stator and another has a 6 pole. Bolt spacing may be different on the engine. When you get into different styles of Chinese scooters you can find so many differences that it's ridiculous.

Another note; you mentioned to go for the gold CDI. It doesn't necessarily make any difference. Myself and other members of my forum and others have found that you never really know what you're getting just because you buy a certain colored CDI that looks like the rest. Your best bet is to stick with one seller if you find a good CDI. Some models that look the same will have a flat timing curve while others will have an actual curve where timing changes for example.

I'm not defending cheap CDIs. I have a video (not trying to promote but just again FYI) that tests a couple of CDIs. They work, but not with gains as claimed. Don't believe any claims from sellers that a 2 minute modification will get you 10% horsepower and speed increase. If it sounds too good to be true, it usually is.

Anyway, good luck with the rest of your scooting experience and if you need help I'm easy enough to find."

It makes me feel sorry for sellers. This fellow was ready to have the seller pay for his starting system if he hadn't figured it out, when it's 100% user error (again unless they sold it as DC and I did a real quick search and didn't see a CDI at that price point from that seller to check the listing). I'm certain this sort of thing happens regularly.

I believe he said he was hoping it would help him get to 75(MPH) a little easier. More proof that my 150/155cc is the slowest in the world because I could only get it into the 60s.

[90GTVert]

The video creator replied : "My bike is an AC system not dc. I bought a second CDI recently and it worked fine."

Didn't know they made gigantic AC CDI boxes. When I look up Puma, it comes up as DC.

[tortoise2]

My bike is an AC system not dc.

The original CDI is definitely DC . . verified by only 1 wire in the 2-pin connector!

He will probably experience an "epiphany" eventually, while evolving through the learning curve to the 75mph "irrational exuberance". For comparison . . the Sym 4-valve liquid-cooled 171cc specs around 72mph.

[90GTVert]

Feb 25, 2017 11:50:55 GMT -5 tortoise2 said:

verified by only 1 wire in the 2-pin connector!

Nice catch. I was trying to look at the wiring, because I believed he was wrong. I couldn't tell much, but now watching again in full screen 1080P I can see that. I won't argue with him about it, just good to know. I did notice that when I searched for Puma CDI info, a gold CDI box came up that was labeled as DC and larger than the AC aftermarket CDIs. Perhaps that's what he was referring to when he said to stick with the gold box, rather than just the gold version of the one he tried? Either way, I guess he's got a CDI that works now so he knows more than us.