Modern Vespa

It seems good to me, but I don't want to blow a piston

Looks a bit wet around the base like it was flooded a bit or kicked over a bunch before starting? But, the tip looks yummy chocolaty brown.

(Temp gauge is worth the 45 bucks imho just for the extra insurance.)

Ok cool, to make sure it's not to hot with using the gauge what temp should it be

I don't have a smallie anymore... I think they tend to run a bit hotter, but someone correct me if I am wrong.

Your temp is gonna vary a bunch depending on how your riding. On a large frame I always use 300 as a marker to back off and let it cool off. Seize zone is probably somewhere north of 325...

Again, IIRC it's higher on a small frame.

(PS - do not confuse my post count with mechanical expertise... I am a shade tree wrencher that excels at swilling booze and attempting to get my scoots tuned.)

Ha yeah me too, it's the best way to have fun doing it !
Thanks for the help though cause I don't wanna toast my bike
For the most part I'm doing city riding but I'll keep that in mind for longer rides
Thanks for the help dude I appreciate it

With temp gauges a lot depends on how you set the sensor up. They won't incorrectly read high - but it is more getting used to your readings and then (somehow) picking up an unusual spike in time. Some argue that exhaust temp is better because will spike faster than the head - still need to spot the spike to do anything. Be useful if you could set an alarm limit on them.

I've always been told you don't wanna be above 350º but that was for higher revving engines, not sure about a Vespa specific number or if it would be different at all. Safe bet would be to stay under 350 either way I suppose

Good to know.
Thanks mate

CHT is an effective tuning help and also great gauge to monitor for sudden changes, a la sprung airleaks, exh leaks, etc. But for actual hi-end tuning, EGT is the way to go. That said, I would only ever bung a pipe for EGT if it was a race bike.

Typically, cast cylinders can withstand higher temps over alu/coated cylinders, but I wouldn't push an alu over 320, nor an iron cylinder over 350 CHT. At CHT temps there, you're piston dome is much hotter and getting awfully stickky.