Thanks for that Darren,
I was slowly coming to the conclussion that I was a complete nutter, I feel much better knowing that not everyone went to the NASA motorcycle engine design school. But I am realy pleased that there is such a wealth a technical knowledge and ability within the forum (it makes up for my lack of both)
Compression ratio, ignition timing, CHT & EGT measuremen
- James P
- Oil Injector
- Posts: 582
- Joined: Mon Mar 11, 2013 10:47 am
- Location: Sydney, Australia
OK - I'll have to defer to you, due to my limited (and long time past) experience with water-cooled engines. I have a selection of eroded (not quite holed) pistons from air-cooled engines, but maybe that doesn't count on this forum!TwoStroke Institute wrote: If you don't have a big box of holed pistons you haven't been trying either
A air cooled head has no buffer to temps like a water cooled head has, under plug temps will be slow to react with a water cooled head, ie the exact opposite to a air cooled head which will show a marked ride even under a 20 sec pull on a dyno.
If you want to find differences take it to the dyno. Leaner will fell faster up to a point and one jet should make 50deg F change in EGT.
Hate to harp on it but you won't get any meaningful data on the road unless your holding at least 140 on the freeway, EGT is for WOT not part throttle.
I'm still going to try the gauge set-up, even if just to prove you right !
Regards,
James