In need of wisdom

[MAS Tequila]

If it doesn't ping you will be ok.

MT

Originally Posted by Dean

Mas T......

I have a question. My 06 1500FI owner's manual calls for 90 octane... The pipes are sooted up. I have very seldom run anything but 90 octane...87 once or twice and 89 a time or two, 93 once because that was the closest to 90 at that time...

So if I try to 89 for a while with no pinging, then there should be no engine damage, correct? And I could try the same with the 87 as long as there is no pinging....

I have the correct plugs per the book for "normal" riding and not racing.

Your thoughts?

[pjandbee]

Originally Posted by MAS Tequila

Run the lowest octane that you can without detonation.

Anything else WILL result in carbon buildup.The ignorance being presented as expertise is unbelievable.

MT

https://www.bellperformance.com/blog...Octane-Ratings

Most people think that higher octane in gasoline supercharges the combustion in an engine cylinder, giving them additional power and performance. It is this misunderstanding of what octane actually does which leads people to spend more on gasoline than they really need to.*

The octane rating of gasoline essentially tells you how much the air-fuel mixture can be compressed before it will spontaneously ignite. Gasoline with an optimal octane rating performs best in an engine designed to run on that octane level.

Lower octane gasoline like "regular" 87-octane gasoline can handle the least amount of compression before igniting. The compression ratio of your engine determines the octane rating of the gas you must use in the car. This is the same as saying your engine is designed to perform its best with a specific octane rating of gasoline.* A "high-performance engine" has a higher compression ratio and requires higher-octane fuel to prevent it from prematurely igniting fuel before the spark plug does it.
So, octane does not enhance the explosion in the cylinder like most people think. What does octane do? It just prevents the air-fuel mixture from igniting before the spark plug does it. Firing the air-fuel mixture at the proper time gives you the maximum power your engine was designed to get.* Using higher-octane gasoline than your engine is designed to utilize is only wasting your money

Glad to see it explained so well. The looks I've gotten trying to brake it to my friends. No problem, they just keep paying the $.25 per gallon more for pretty mush nothing. Oh well.

[Dean]

OK, thanks.

[vulcanscott]

Glad it was just Carbon Buildup .

[DragonLady58]

Originally Posted by vulcanscott

Glad it was just Carbon Buildup .

What He Said! Regardless of how the Big Vulcan 1500 Big Twins look, they are not Harley. Can do a damn good job of sounding like them, can run like them, memick them, but past the big VTwin Looks, they are 2 completely diff. animals.
The Harley engine is old turn of the century technology, thats been upgraded to deal with the old techs shortcoming and make it modern.
The 1500 Vulcan is new world technology, designed/built for reliability and performance to be a cruiser, looking like the old Harley Engine.
The old Harley design, the rear cylinder always ran hotter than the front. When cruising down the highways, every so often, you needed to back off on the throttle, allowing oil to be flung up on the rear cylinder wall/piston. MaKawa has oil jets that squirt oil onto the cylinders. Pushrods vs timing chains....I could spend all day here....
Regardless of the 1500 looks, it loves to rev. Reving it won't hurt it. Its liquid cooled. It can run at 90 mph in the desert, in the city or on the interstate, all day, all week, all year, for decades pushing a big windshield thru the air, saddle bags packed, loaded with touring stuff. All it asks is keep good gas in it, clean oil and filter, clean the air cleaner, bugs outta the radiator, and a few minor repairs along the way. Yes, things will wear out!
On a Harley, at 35,000-45,000 miles, almost like clockwork, your gonna have to go into that harley engine and freshen things up. Yes, they can run longer than that if taken care of, but you'll damage parts doing it.
The Vulcan VTwin can go over 120,000+ miles easily before needing a overhaul, if taken care of.
And Yes....you gotta rev them up to blow that carbon out, OR, do as this fellow member did, use some SeaFoam that breaks that stuff down so it can get blown out.
As MAS said, carbon buildup can raise your compression ratio, so your motor will start pinging on lower octane fuel. It will build up in certain places and start causing wear.

So, get the big beast out on the road every month, and rev her up going thru the gears. As long as your engine isn't knocking, have really loose timing chains, or have low oil pressure....going 40 in 1st gear, 60 in 2nd, 80 in 3rd, you ain't gonna hurt it. No, you don't have to rev it that much, just take it out on the road and run it vigously once a month to decarbon it. Just ride it like you have a pack of Angels on your ass!
If your worried about reving it and blowing the engine, remember, these bikes have rev limiters built into them! You'll be suprised how well it'll run after you do that!

[MAS Tequila]

The carbon build up will cause hot spots that cause early detonation.

One of the reasons some bikes which are mechanically identical detonate and some won't is hot spots.

It can be as simple as a little casting imperfection or rough spot in the chamber.

That is one reason I believe a little porting and polishing is a must when you put an engine together.

Not necessarily enough to make a huge difference in air flow, but enough to remove the hot spots.

But it's not as simple as just polishing the entire chamber.

There are areas which cause the mixture to swirl correctly that you don't want to touch.

The rev limiter IS your friend, go bounce off of it a few times.

Like DL commented, it WILL make a difference.

And for God's sake, don't turn your idle down to make your bike sound like a HD.

You WILL not be getting adequate oil flow at the lower rpm's, which should not be less than 900.

Many HD owners are ruining their engines by slowing the idle to get the sound.

MT

[alwhite00]

I have a 2000 1500fi and I believe it calls for 90+ octane. I have V&H exhaust and a TFI programmer. I have been running 92 octane because of what the manual said, will it run OK on 87?

[DragonLady58]

Thats the reason why I run regular+a good octane booster. My bigbore 1500 loves it.
The 87 octane if boosted runs good because of the way I have it set up.

I'd say if it doesn't ping or rattle with 87, just run that.

My 1500 is 10.25 compression....and the reg. with 10-15%Ethanol is fine as long as I run my octane booster.

[Jim1955]

OK so is the 45-1st, 60-2nd,80-3rd.......schedule something that should be done often like every few thousand miles..........and do you run it in each for a few miles or just hit that speed then shift. This is the first time I've heard this so just asking questions.

[DragonLady58]

Just hit that speed and shift, all you want is to turn it up to blow out all that crap that sticks to the heads and valves....you be suprised of all the crap that comes out....

[MAS Tequila]

Don't worry about what the speedo says, don't even look at the damn thing.

Twist the throttle hard and hang on.

When you feel it bounce, you'll know it when it happens, shift and run it out again.

I usually find a long straight empty road and go through 3rd bouncing off the rev limiter on occasion.

I find myself preoccupied with watching the road and haven't checked the speedo.

You'll like the results.

MT

[Jim1955]

OK, so I took the bike out today to try this bouncing it off the rev limiter but I didn't take it up to above 6000 rpm, I hit the 6000 in both first and second gear, doing 75, and then just went into third, did that two different times and didn't notice anything different with the bike. So did I not take it to a high enough rpm..... or what?

[MAS Tequila]

You will know it when it bounces off the limiter.

If you have to ask, you didn't do it.

MT

[Jim1955]

That's what I thought...............

[DragonLady58]

Originally Posted by Jim1955

OK, so I took the bike out today to try this bouncing it off the rev limiter but I didn't take it up to above 6000 rpm, I hit the 6000 in both first and second gear, doing 75, and then just went into third, did that two different times and didn't notice anything different with the bike. So did I not take it to a high enough rpm..... or what?

Well you should be good for about a month or 6 weeks....just do it once a month or so....keeps buildup down....