Octane
- Thread starter COOPer
- Start date
Back in the 70's the valves came with a coating to address the loss of lead in the fuels. The lead acted as a cushion so as not to wear the old style valves out.
Here is how I think just plain old pump gas handles it. How many years old is the BD?
How many burnt valve threads are posted on this forum as being the #1 problem of this bike?
You are now adding lead back onto the seat that meets the valve. So solid-liquid-gas-HEAT-sticky-solid coats the exhaust port, plus the back of the tulip of the valve is that 'for every action ='s, that says liquid back to a solid... ever hear of decoking?
Field test wise, I prep track bikes with the highest pump gas and add so much octane to the gas cans. I keep packing the same bikes up the truck ramp to head out again, than up the shop ramp and change out burnt pistons.
The good: Go head, make my valves last longer.
The bad: Can't create or destroy matter so it don't matter you leave a carbon deposit in the water table.
The ugly: The contraption you'd have to make to steam clean the combustion chamber as you ride = No coking needed.
Signed,
No tickey no washy
Here is how I think just plain old pump gas handles it. How many years old is the BD?
How many burnt valve threads are posted on this forum as being the #1 problem of this bike?
You are now adding lead back onto the seat that meets the valve. So solid-liquid-gas-HEAT-sticky-solid coats the exhaust port, plus the back of the tulip of the valve is that 'for every action ='s, that says liquid back to a solid... ever hear of decoking?
Field test wise, I prep track bikes with the highest pump gas and add so much octane to the gas cans. I keep packing the same bikes up the truck ramp to head out again, than up the shop ramp and change out burnt pistons.
The good: Go head, make my valves last longer.
The bad: Can't create or destroy matter so it don't matter you leave a carbon deposit in the water table.
The ugly: The contraption you'd have to make to steam clean the combustion chamber as you ride = No coking needed.
Signed,
No tickey no washy
I haven’t ever. Sounds like it could cause a problem. I have been running the super, but just started running the 91 octane ethanol free at Wawa. Seems to run just as good as the 93 octane. Had a bunch of riders say the ethanol is the real killer to carb & motor. We’ll see how that works out.
john sachs
Well-Known Member
We run VP Import in the Pro-Mod bike. Never anything but pump gas in street bikes.
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Butch Cassidy
Active Member
... unless your CR is 10:5-1 or more... it has no benefit. Power is made from: compression/ combustion and fuel/air ratio. Increasing or decreasing one without adjusting the others is a fool’s errand and likely not to end well. Too much of anything is not good.
Great pics John. Seen this at the chopper show in February.
Mikeinjersey
Well-Known Member
Just for your Info. In the BD owners manual it states an Minimum Octane of 87 with ethanol fuel but doesn't mention the Max recommendation. I'm not sure what S&S says on the subject.
john sachs
Well-Known Member
If you rid your engine, properly, of all the EPA crap, and raise the compression ratio to where it should be, you better NOT try running 87 octane anything, unless you live at the top of Mt. Everest.
John