[Jamesdover300]

I have a 88 Trx300 I changed the ground on the battery and the starter relay I started it and let it run for about 30 seconds then it started to smoke from under the front plastic now it won’t spark no more can y’all help me out

 

[Goober]

Check your CDI to see if you smoked it. You may want to check you regulator/rectifier

 

[Jamesdover300]

I took a cdi off a of a runing bike it still has no spark and I don’t know how to check the regulator

 

[Goober]

What year CDI did you use? I think the CDI year groups are 88-92, 93-95 and 96-00; can’t interchange those. @SamUK please correct me if I’m wrong.

How does that replacement CDI look now?

Download the service manual from the links in my signature block. You will need a multimeter to perform any diagnostics tests.

You can also use my links to search parts suppliers for proper part numbers. I only buy OEM parts, sometimes thru the dealer, Partzilla, Rocky Mtn and fleabay. Some sellers will list parts “OEM spec” or even list the OEM part number with “aftermarket” brand.

 

[SamUK]

@Goober yeah your close enough with the dates, they do overlap a little though on some bikes.

98-00 (Gen3) won’t fit Gen1 or Gen2 bikes, and only some Gen1 and Gen2 cdi’s will interchange. The plugs are slightly different but can be modified carefully to get a successful fitment.

To the OP, avoid cheap Cdi units off eBay and Amazon, there Chinese and usually go up in smoke, buy used OEM or Ricks motorsport electrics. NOTE: Ricks do not sell on eBay,( I asked him personally) some sellers are branding there units as Ricks.