Premium User

An Engine doesn't know what it's on, only People Do!

Engine Life(Hrs) has more to do with the Person who Builds it, the Person using it, and Person Maintaining it, using Good Fresh Octane Gas with Good Oils, and doing Good General Maintenace, Plugs, Timing, Oil Changes, etc!

Old Stock Cont. 084ci, 4 Stroke Motors, off Military 10kw Generators used on Kitplanes at 3600rpm made over 1000hrs, 20+ years ago. Today, you have better Oils, Metals, Technolgy, to use in these Motors. Simonini 2 Strokes have a 600hr TBO, Hirth 2 Strokes a 1000hr TBO, Rotax 2 strokes 300hr TBO, all using Higher Rpms. Rotax 912(80hp) 4 Stroke 1500+hr TBO used at 5500rpm continious.

Yes, I did say, "Continuous 4800-5000rpm on a Mini Air Boat or Snow Glider, Hence Endurance is the key Factor.

You have Set variables Max 5500rpm, a Max Safe CR for 93 Octane, Max 389cc, everything else is up for whats best to use!
Well you sound like you have youhave everything figured out for your 390 e


Premium User
This guy sounds. Like he has it all. Figured out . and he has Carlson Motor Sports. One of the best and most helpful. Outfits in the. Sport of kart racing and engine building trying to help him and he wants to. To argue . .....WOW


Premium User
The 390 Honda is used for the Mini Cup cars.
It is very close to stock and makes around 16 HP on gas on my dyno at 4000 rpm.
It makes 22.3 LBs or torque at 3500 rpm.
It runs a very long time without needing attention.
How long i can't really say since people usually get them refreshed every season weather they need it or not.
Like Brian said "My point is, it's pretty easy to build a reliable 30 CHP that's somewhat affordable"

OOPS i just noticed that this discussion started in Sept of 2017 and was just brought back to life May 18, 2019
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