Cam timing out.

[Superflash]

Hi, by holding the pin in its groove and turning the bowl upside down. Have also just pushed the float needle down gently until it seats. Getting the same result either way. Wondering if this carb is home to some gremlin that's out to do my head in. 🤔

[cdsdorset]

And what height are you setting it at.
( sorry just read back to your previous post)
You are better off measuring the fuel height.

[Superflash]

You could be right. I've still got the original MK1 in a box somewhere, so I'll grab the bowl plug and tap a hole to take a clear hose. Let you know what I find.
Cheers

[Allan G]

With the clip on the lowest groove , it'll be really rich.
Try the centre groove to start with and the pilot screw right in and back out 1.5 turns.

All thunderbolts should have the needle clip in the top groove for the leanest carb setting.

The Trispark ignition is great, I have fitted a couple of them BUT you must follow the instructions completely to the letter. You must also check you are following the instructions for your model. There are subtle difference's between the 005 and the 006 model ignitions.

You must also set the ignition to full advance when setting the timing, easiest way of doing this is to use the crank locking tool that enters the front of the crank case. This also stops the crank turning the engine under its own weight.

[V500]

Top groove would be the richest setting?

[rhyatt]

with the clip in the lowest groove/notch, the needle is held up higher in the throttle slide therefore richer.
conversely , with the clip in the top highest notch it is pushing the needle downwards and weaker

[V500]

You're right of course. I blame the merlot..