First thing's first. Queue this up to set the mood.
So I bought someone else's built Vesper motor (got damn you must be stupit!). Nah, I just like problem solving and I'm not a complete scrub. It is a good setup so I didn't really want to pass up on it, yolo. Also the ad said jet, bolt, and go. lol sure. We'll see about that sonny. It is this build actually, But I bought it from the guy that bought it from the guy that bought it from this guy or something. Idk it's a slut. I'm not gonna go too much into the parts rather focus on what needs to be discussed. I will try to lay out exactly what I have done so you can be like "you fucked up right here you dip shit". Maybe this will help other peoples.
To start, I just slapped some jets and a needle in the 17.5 phbg. Stock idle and stock starter, stock needle, and I think 85 main? Idk, whatever the next step up from the stock size I had. Doesn't matter, that's fine. I also put a pull choke on it because I ride my shit all year and I like when it starts.
So it had sat for 2 years in the most recent owners stockpile. Why you'd buy something like thi$ and just sit on it is beyond me, but to each their own. So for safety's sake, I poured an arguably unreasonable amount of 2 stroke oil into so as to not have a dry start for the bearings and let it sit for a few days to properly cure, stirring occasionally. I was also waiting for parts in the mail. story of my life.
The CDI that is on it is a stock Piaggio ducati 3 coil job.
5 wires. Yellow and Brown are lights. Red is the pick up/pulsar coil, Green is the exciter/charging coil, white is a ground. Had one of the blue Ducati box/coil combos. Fancy!
All of the wires from the stator were initially black with zip ties or tape to identify the color, and that's fucked. I want the Italian flag colors dammit. So I bought fancy silicone wires that are extra noodley and soft and soldered them at the coils. fine and dandy. Cool!
Mounted the motor and the pipe and stuff.
I had mocked the wires up to the CDI box/coil and just kinda jammed them in there against the spades, just to make sure the timing was good and it would fire. Presto, worked fine. Fired up after a little starting fluid since I dumped so much oil in it. Smoke pours out the pipe like big king chief vape master, it was hoot. That eventually dies down.
This is where I think I fucked up, or at least this paragraph (mostly the bold part) will be what I attribute to my problems. It is now time to turn it off. I grab the black wire and touch the frame, Nothing. ok... how's this work then? Touch the white wire(ground), nothing. Touch the red wire, that cuts the spark, ok. Quickly remove it, engine keeps running. Touch green, also kills it, I let it shut off this time. Good to know. I start it up a few more times and kill it in a mix of red or green.
I cut my wires to length and add the female spade doodads on them and hook everything up. Now I have a hard time getting it to start. wat the shit. I go through the dance of checking for spark and timing and what have you and it eventually comes back. Cool, hook it all up proper again and it starts up.
The motor is now warm so it's time to try and rev the bitch to the moon and explode my clutch bell. I try to do so. RIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN-DIN. Sounds like it's bouncing off a rev limiter like that old V-Tec. what the hell is going on. check the timing and it's firing like 180° off when that is happening and it is not revving very high. huh. that's probably not right. I kill it again and give it a think.
I try to start it up again. Now I have no spark at all. fuck. Did I kill the CDI box? probably. You stupid shit. whats more money into this amirite?
$75 for a box/coil with static timing is way too much money so the blue ducati can get bent. I'll find another way. So I look around and find and buy this Jog box since it has a curve.
and even though I have like 10 HT coils in my pile,
$23 total shipped. Pretty damn good.
I hook all that shit up like so
It sparks, bike fires right up. Super easy. Lets see if it's still doing that weird shit with the off timing.
Yes. Yes it is. What the hell. I check the voltages from the coils and the exciter is pushing like 85VAC under a drill which is plenty considering the low speed. The pickup is doing like 5VAC which I think is fine. HM. I still suspect the pickup coil is bad. What about the pick up when it is actually running? So I took a video to share with the internut. I think Pickup Man should be done or done enough by now, so it's time for a new vid anyways.
This is from a cold start after sitting all night. The jetting is not great, but it gets the point across.
Notice how during the weird "rev limiter"esque effect the pickup coil voltage drops significantly. It also seems to get worse as the motor gets warmer and the rev limiting effect moves its way down the RPM range. This is good data I says.
So it's time to pull the coil and see if it's dickered. It has this big fucking hole in it. Im not sure if that is just a bubble from the epoxy pour or if I actually popped it. the pic is from after I poked it some with a screwdriver, just the tip and only for a minute mind you.
The symptoms remind me a lot of when people have problems with the cheap Treats e50/ZA50/505/whatever CDIs and the pickups fail on those all the time. I think I cooked it whist frying the cdi by touching the kill wire to the pickup wire. Like a goddamn idiot.
Maybe it was busted when I got it. Yeah that.
TL;DR is my pickup broke? Probably.