Stupid question regarding Coleman Q77, Q99, and R55 generator jets...

Yes, the slant burner tubes are the shortest of their era. Looks correct to me. I've run longer tubes, but I couldn't tell any difference.

Warmup time is dependent on ambient temp. The pulse you're seeing is from the leidenfrost (might check that spelling) effect. Basically the cold liquid fuel is rushing up, vaporizing which forces the liquid back down, then it comes up again... This bouncing back n forth can be seen in the form of a pulse in the mantles. Once the liquid fuel warms up though it'll generally stop, unless there's no, or not enough packing in the generator to act as a buffer to slow the liquid down. Funny enough, kerosene burning lanterns don't seem to suffer from this issue... Probably because of the higher flash point, or maybe the heavier viscosity? I'm not certain.

 

@Toby Garner thank you sir! thats enough explanation for me! Much appreciated!