Qt50 starting no more.

I just spent a lot of time on my 79 QT50. I got a PW50 stator and changed it out.

Now it refuses to start at all. Before any of this happened I assumed to my carburetor was the problem so I switched to a clone carb and then switched to an 84 QT50 carburetor. Have not had any good luck.

I did have a little spark with the old coil before I pulled it out of the flywheel area.

Now I have nothing.

Would it be safe to assume that, my cdi is at fault?

Also, would really shity soldering wire cause any problems? It's meant for electrical but it doesn't seem great.

If it is likely CDI at this point, where can I get one or what works for this? Drop me a link please?

Re: Qt50 starting no more.

Just my opinion how I would attack this. Put all correct original stuff back in, get it starting/running correctly then modify it 1 step at a time.

Re: Qt50 starting no more.

Already did this.

All is back but still no spark.

_Wondering about the cdi box.

_And soldering wire.

the box is not original to my 79.

All original wiring was stripped out for it to be a pit bike.

Looks like the box came from a dirt bike?

I bought it this way.

This WAS my best qt50.

Re: Qt50 starting no more.

There are two different CDI boxes. I'm pretty sure it has to match ign switch- two position or 3 position.( 79-81 two position, 82-87 three position)

Re: Qt50 starting no more.

If the joints are shitty it's your iron not the solder. Unless your using lead free solder, that stuff is horrible.

Re: Qt50 starting no more.

I think Bob might have got you pointed right newer has start and run

Re: Qt50 starting no more.


So, this moped has had it's wiring gutted. This is a cdi box of some type that seems to replace some of the way this thing once worked.

-There is a box just like this running from Ignition coil and into stator coil area.

-Key system has been bypassed. I have a killswitch installed to be able to shut it off and it worked this way since I got it in this condition.

***I hope to all moped gods that its just a wire nut loose or just corrosion.

Yes, wirenuts were used on the connections on the moped

Re: Qt50 starting no more.

Some of these guys know better than i do but i think that is part of the ignition that gives it extra spark to start when you have the switch set to start position...mine is 84 and has that but i can't say on the older model

Re: Qt50 starting no more.

^ It's not xtra spark it is a rev limiter, so it does not take off, stupid safety thing for stupid people, and because lawyers...lol, mine does not have this, it's an '80, even if your key switch has been bypassed you can tell if you had it, will say off start, run if it did not come that way, it will say simply off/on.

Re: Qt50 starting no more.

This might explain why my 79 accels way faster than the 84 my girlfriend has. They both top out around the same. The 84 is still original, wiring harness only disconnected at the moment.

I assume that this is needed? Hers has the gray aluminum box that it came with.

Mine just has this weird box.

Re: Qt50 starting no more.

Stephen probably knows for sure but i think that has to be on it for it to start on the 84..

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account