Jetting

[deward66]

I am having a problem jetting my 100cc Dirt Squirt. I have the '76 aluminum cylinder engine. It is jetted according to the parts book but cannot get it to rev much past an idle. Opening up the throttle causes it to bog down and will die if held there. If I let it back down to an idle it will run all day long but spits nasty looking black drops from pipe. I have run the needle clip in every slot with no real difference in performance. I have a 150 main jet in it. Plug comes out wet but still firing.
Looking at the Dirt Squirt or Road Toad with the cylinder painted black, it has a 2.0 slide and 5F18-2needle. I believe this should be a leaner combination?
I am just also wondering why the difference in jetting between these same year bikes? Is the porting different between the two cylinders causing the different jetting?
Any help out there?

[olddogs]

Take the exhaust nut off the cylinder and let the pipe hang loose. Try starting it. Typical symptoms of a clogged pipe. Old oil buildup or squirrels filling it with nuts. Betcha that solves your biggest problem. Jetting over the internet much harder to solve.

[deward66]

Thank you for the reply. I burnt out the pipe before putting it on but will take it off and try that.

[Dale]

If your pipe is proven to be clean then confirm that your ignition is good working order with a fat blue spark and timing set properly.

What are you running for fuel and oil? Are you using oil injection or pre-mix? If pre-mix, what ratio?

As for the carburetor, I have found the 5EL9 on the 4th notch to be a good choice for both Road Toads and red tank Dirt Squirts. This was the spec needle for the 02 Road Toad. Yes there were changes between the different models of Toads and the Dirt Squirt and I think this was just part of the changes made to address issues with the first 99 Road Toads seizing.

It is also possible that your needle jet (nozzle) is worn excessively or is not the correct size. Should be an O2.

What Pilot Jet are you running?

The specs for the 02 Road Toad are Pilot 30 (opt40), Main 160, Needle 5EL9 4th, Slide 1.5, Nozzle O2. I have found these specs to be the best for my red tank Dirt Squirt and 99 Road Toads (using the 30 Pilot). Your results might vary, be careful making your jetting selections!

[MTrat]

Check your carb float for proper condition and installation...

[deward66]

I want to thank you guys for the responses. After removing the pipe I found out that it wasn't the one that I had already burnt out. Put the burnt out one on and it runs fine.

[Dale]

Awesome! Thanks for the update. Olddogs nailed it.