jetting opinion

[jetmechmarty]

My plugs have a little color on them now. I have smooth acceleration at all RPM. 33 MPG riding it in the mountains and at 70+ MPH on the highway. My plan of action is to mess with it no more.

[jetmechmarty]

My plugs have a little color on them now. I have smooth acceleration at all RPM. 33 MPG riding it in the mountains and at 70+ MPH on the highway. My plan of action is to mess with it no more.

[bikerphil]

My plugs have a little color on them now. My plan of action is to mess with it no more.

Awesome, that sounds like an excellent plan, just ride and enjoy those roads you are so lucky to have.

[oldnortonrider]

I replaced the needles and seats. Does it matter which way the needles are oriented on the floats? My airbox is still filling up with fuel. I'm at a loss. Why can't I get this right?

If you're just tuning in, this is an on going issue for me.

Jet; do you attribute that you were successful to stop the flooding into the airbox because of the gasket trim, or because of the replacement of the float needles?

[donebysunday]

I'm into this job now. My camera is MIA.

Jetting is 110-120-120-110. The plugs are light gray to white. 2 & 3 are whiter than 1 & 4. What gives?

For the time being I'm stuck with no transportation. Any suggestions?

I have verified the jetting. Carbs are open and I'll have to look at spare XS650 carbs to see if they have anything to offer.

Hi Marty !

I know you should not change 2 or more things at one time but I did. After having the light pink plugs with stock pilots set at 4 turns out and the stock airbox w/K&N. I DID change the plugs to BP7ES and the pilots screws to 2 1/2 turns out, still running the 120 mains on this 81 LH, now #1-4 are still pink #2-3 light grey, grey is not good so I'll open up the middle to 3 1/2 on the pilots. Bike runs great but don't like the grey. This coloring was from a 40 mi. thrashing getting me like 21 mpg. and a return home winding hilly mix of 15-55 mph. getting 39 mpg. ? ? ? ?

[jetmechmarty]

Jet; do you attribute that you were successful to stop the flooding into the airbox because of the gasket trim, or because of the replacement of the float needles?

I wish I knew! I may have had a needle hanging up. It only takes one to dump a lot of fuel. It is now running perfectly. It starts instantly, even without the choke. It pulls hard everywhere. It's as right as can be. Many thanks to JeffH for really making it right.

[jetmechmarty]

Hi Marty !

I know you should not change 2 or more things at one time but I did. After having the light pink plugs with stock pilots set at 4 turns out and the stock airbox w/K&N. I DID change the plugs to BP7ES and the pilots screws to 2 1/2 turns out, still running the 120 mains on this 81 LH, now #1-4 are still pink #2-3 light grey, grey is not good so I'll open up the middle to 3 1/2 on the pilots. Bike runs great but don't like the grey. This coloring was from a 40 mi. thrashing getting me like 21 mpg. and a return home winding hilly mix of 15-55 mph. getting 39 mpg. ? ? ? ?

I've had some very crappy gas mileage, but I don't know that I've had mileage as low as 21. Why the BP7?

[donebysunday]

I've had some very crappy gas mileage, but I don't know that I've had mileage as low as 21. Why the BP7?

BP7ES is colder, same as the XS650. NGK is hotter as you go down in number, thought it might help the color ?

[MPittma100]

78E Jets

Marty, I changed the stock jets in my 79SF to the stock jets (and pilots) that were in the 78E. The performance "feel" was noticeably better. The mpg went down from 38 to 35 mpg, but I like the performance enough to not change back. Plugs have plenty of color with factory exhaust and aftermarket coils.

MP

[MPittma100]

Why does NGK do that?

BP7ES is colder, same as the XS650. NGK is hotter as you go down in number, thought it might help the color ?

Good point about the way NGK publishes heat ranges. Like you said the number is hotter when it is less.

Every other plug manufacturer's heat ranges are hotter as they go up. One can easily be confused with this "opposite" method.

MP