Harley Davidson V-Rod Forum banner

1 - 3 of 3 Posts

·
New England Rider
Joined
·
12 Posts
Discussion Starter · #1 ·
I get clicking on acceleration and use 91 and 93 Octane faithfully. I was told that this is because with an '03's 3.7 gal tank and stations using 1 hose for all Octanes the amount 87 Octane left from the previous pump user can be as much as 1/2 to 3/4 gallon. And dilutes the fuel as I fill up.

1. If I pay 25 to 45 cents a gal more for gas how do I get the 91/93 I pay for.
2. How much gas is "stored" in the hose.
3. Could this be the cause of clicking?

Any others experience this?:spank:
 

·
Registered
Joined
·
597 Posts
You are correct that 1/2 tp 3/4 of a gal. of the previous pumped fuel is in the hose. If you are filling up only 1.5 to 2 gals you can do the math and see how much of the lesser grade you might get.

As to the noise you hear. If it is indeed "pinging", it is detonation NOT preignition. Two very diiferent fuel buring issues. Detonation is the the simultaneous explosion of the end gases of a buring fuel charge( the end gases are being compressed as the fresh charge burns. And even though the piston is moving AWAY from top dead center, greater chamber area, the area with the remaining unburned fuel, is reaching very high pressure. ) As those end gases exploded ( all at one time, as opposed to burning, causing extremely high PEAK cylinder pressures ) you hear a sound like a ping. It is a mechanical vibration in the combustion chamber.
Lighting the mixture to far before TDC ( too much spark advance ) can lead to detonation.

Preignition is the early "unintended" lighting off of the fresh charge of fuel before the igintion by the spark plug. ( after some time of continued DETONATION a hot spot in the chamber might be the casue of preignition !!)
Once started TOO early the buring gases reach very high temperatures during combustion,( the piston is still moving up or very near TDC while a very large portion of the charge is burning ) and may result in holes being burned in a piston. The temperature of the buring gases under compression exceeds the melting point of the piston material.

( the big problem with detonation is over time it will "hammer" away at piston and rings and do damage. It may also lead to preignition due to hot spots!!
Preignition events are very SHORT lived as they do major damage very quickly )
 

·
O5' CVO - $12,000
Joined
·
707 Posts
FatbyRR said:
You are correct that 1/2 tp 3/4 of a gal. of the previous pumped fuel is in the hose. If you are filling up only 1.5 to 2 gals you can do the math and see how much of the lesser grade you might get.

As to the noise you hear. If it is indeed "pinging", it is detonation NOT preignition. Two very diiferent fuel buring issues. Detonation is the the simultaneous explosion of the end gases of a buring fuel charge( the end gases are being compressed as the fresh charge burns. And even though the piston is moving AWAY from top dead center, greater chamber area, the area with the remaining unburned fuel, is reaching very high pressure. ) As those end gases exploded ( all at one time, as opposed to burning, causing extremely high PEAK cylinder pressures ) you hear a sound like a ping. It is a mechanical vibration in the combustion chamber.
Lighting the mixture to far before TDC ( too much spark advance ) can lead to detonation.

Preignition is the early "unintended" lighting off of the fresh charge of fuel before the igintion by the spark plug. ( after some time of continued DETONATION a hot spot in the chamber might be the casue of preignition !!)
Once started TOO early the buring gases reach very high temperatures during combustion,( the piston is still moving up or very near TDC while a very large portion of the charge is burning ) and may result in holes being burned in a piston. The temperature of the buring gases under compression exceeds the melting point of the piston material.

( the big problem with detonation is over time it will "hammer" away at piston and rings and do damage. It may also lead to preignition due to hot spots!!
Preignition events are very SHORT lived as they do major damage very quickly )
Wow, great explaination! :thumb:

What an education........! Thanks FatbyRR.
 
1 - 3 of 3 Posts
Top