Is premium fule neccessary?

Norm

Member
Joined
May 31, 2008
Messages
56
Is there any way to tell if your motor likes premium better than reg unleaded?
 


H

HoughMade

Guest
Mine runs fine on 87 octane. What does the owner's manual say? If an engine is not designed to take advantage of higher octane, it will not help anything (may even reduce power to run on higher) and, that I know of, these small engines are all built to run run on regular.
 
F

fetor56

Guest
I doubt if u would notice any difference in performance between the lowest & highest octane levels....not enough anyway to justify the price increase.
 

arceeguy

Active Member
Joined
May 20, 2008
Messages
1,157
Most small utility engines are designed to tolerate crappy fuel. They have (relatively) low compression and tame ignition timing. This allows them to run properly on fuel that has degraded quite a bit from storage.

This also allows quite a bit of performance gain if you raise compression ratios and advance the ignition timing. (Briggs, Tecumseh and Honda kart engines are a good example)
 
I

Irish John

Guest
Most small utility engines are designed to tolerate crappy fuel. They have (relatively) low compression and tame ignition timing. This allows them to run properly on fuel that has degraded quite a bit from storage.

This also allows quite a bit of performance gain if you raise compression ratios and advance the ignition timing. (Briggs, Tecumseh and Honda kart engines are a good example)
Sounds interesting. How do you raise compression and advance the timing on a Honda GXH or Huangsheng copy? Are there drawbacks?
 

darwin

Well-Known Member
Joined
May 26, 2008
Messages
4,047
If its a true cart engine then were talking apples and oranges here, cart engines cost in the thousands of $$$$ and are not weedwhacker motors.
 

darwin

Well-Known Member
Joined
May 26, 2008
Messages
4,047
I was thinking of those lil formula cars that go like a bat out of **** around the race tracks.
 
H

HoughMade

Guest
Well, a Honda GXH50 ain't a weed wacker motor- generator, perhaps.

To advance timing would take an offset flywheel key and to raise compression would either require a new, taller piston (not likely to find), or you need to machine the head.
 

Mountainman

Active Member
Joined
Jun 15, 2008
Messages
3,579
Subaru regarding the Robin says to burn -- REGULAR GAS -- most of the small engines I have used over the years have called for the same. Happy Riding from - Mountainman
 
Top