If you are 100% sure its not the carb then move on.
There are oodles of possibilities of failure before the cdi... Test test test before spending 300+ on a new cdi
Have you gone thru the entire electical system. By that i mean everything, wire shorts wire opens wire connectors wire switches key/ignition wire coil wire relays. Once everthing has been tested good and eliminated, then move on. In the past 4 months I have had 3 87 and not a 1 was running poorly due to the cdi. The one time I was sure it was the cdi, I changed it with a known good runnig 87 cdi and thought that fixed the problem. Turns out it was a broken wire inside a connector and when I change the cdi the wire remade contact due to the movement location. Another 87 had a kill switch intermittent problem. Everytime the bike was a a certian RPM it cutout miss & pop. Faster / slower was OK. The RPM made a resonant freq./vibration that was enough to make contact.
ps. still curious on the yamaha 117.5 jet. Did you get a mfg/part# on the packing list
ps.. the only way to test a 87 cdi is to swap it to a known running 87
ps...if you want help bring it over, I have lots of 87 parts
There are oodles of possibilities of failure before the cdi... Test test test before spending 300+ on a new cdi
Have you gone thru the entire electical system. By that i mean everything, wire shorts wire opens wire connectors wire switches key/ignition wire coil wire relays. Once everthing has been tested good and eliminated, then move on. In the past 4 months I have had 3 87 and not a 1 was running poorly due to the cdi. The one time I was sure it was the cdi, I changed it with a known good runnig 87 cdi and thought that fixed the problem. Turns out it was a broken wire inside a connector and when I change the cdi the wire remade contact due to the movement location. Another 87 had a kill switch intermittent problem. Everytime the bike was a a certian RPM it cutout miss & pop. Faster / slower was OK. The RPM made a resonant freq./vibration that was enough to make contact.
ps. still curious on the yamaha 117.5 jet. Did you get a mfg/part# on the packing list
ps.. the only way to test a 87 cdi is to swap it to a known running 87
ps...if you want help bring it over, I have lots of 87 parts
