MPG & What octane gas do you use? - Take 2

[MPittma100]

Mpg

Mike I think your decreased fuel consumption is less dependent on the draft and more dependent on the stately speed with which most HDs run


John

Hi John,

I am inclined to agree with you.

Mike

[Bonz]

I gained 1.5 miles per gallon with the FD conversion on average.

[MPittma100]

MPG Gain

I gained 1.5 miles per gallon with the FD conversion on average.

I consider that a substantial increase.

[Bonz]

It sure beats a sharp stick in the eye! LOL. The lower rpm is such a nice thing on a bike of this size and ability to do long distance.

[motoman]

It sure beats a sharp stick in the eye! LOL. The lower rpm is such a nice thing on a bike of this size and ability to do long distance.

These bikes ALREADY have the ability to do long distance rides, as they come stock. IMO, unless one is intending to make the bike their main and only ride, with LD riding being the main purpose, the final drive swap is a downgrade as far as longgivity and drive train load, if your just gonna use bike for local riding and short 1000mi. jaunts.

[BA80]

I STRONLY disagree Brant. I have an 850 FD in my bike that I've had in there since 09. My XS is my daily driver here in town, my long distance bike, and carves the twisties as well as my abilities will allow. Never had an issue with it and I'm NOT nice to it.

The difference is instead of 5K at 70 I run 5K at 80. Other than that the difference is unnoticeable.

It probably isn't necessary on a standard with a 17" wheel because a17" on a standard is EXACTLY the same gearing as a 16" on a Special with the mod.

Maybe someone here with the mod on a Standard will speak up.

[bikerphil]

With the 850 drive, 70 MPH is 3500 RPM with the 17" wheel. It's nice on the highway. It's a little too tall thru town but on the Special with the 16" it's just perfect. JMHO

[Bonz]

I know we'll agree to disagree on this Brant (and others).

The FD swap is a no brainier for me and my bike. Lowered the rpm, gained mpg, and other than Scotty (3Phase) who basically and deliberately ran an FD conversion into the ground on purpose for the sake of knowledge, I have yet to hear of an issue with reliability of any bike components, other than an FD swap/set up not being done correctly and the FD dying.

Sure, the 850 FD is shown to be the choice vs 750 FD, but again, the reliability issue just isn't there in reality with either FD swap.

4000 rpm at 60 mph with a Special is not what i want, and was all about the short stop light to stop light crowd, period.

I would not do the FD swap on a Standard with the stock FD/17" rim. On my G, final gearing/rpm combo is perfect in my mind, which is precisely the rpm the FD conversion gives the Special.

I'll let everyone know as soon as my downgrade in longevity breaks. Ha-ha!

Until then, I will keep using 85 octane here in Colorado and get 37.5 mpg in daily use. I voted 87 octane since that was the lowest choice.

[motoman]

I STRONLY disagree Brant. I have an 850 FD in my bike that I've had in there since 09. My XS is my daily driver here in town, my long distance bike, and carves the twisties as well as my abilities will allow. Never had an issue with it and I'm NOT nice to it.

The difference is instead of 5K at 70 I run 5K at 80. Other than that the difference is unnoticeable.

It probably isn't necessary on a standard with a 17" wheel because a17" on a standard is EXACTLY the same gearing as a 16" on a Special with the mod.

Maybe someone here with the mod on a Standard will speak up.

Seeing that the 850 drive hasn't given anyone grief as opposed to the lighter duty 750 drive, I'll retract that opinion.
The Standard, stock final drive rpm's@ 75mph are 5K on my Venturer. Speedo is also dead-on checked with GPS. I know anything above 4K fuel consumption starts increasing..........but motor is so silky smooth at 5K, it's hard to resist just lettin' it roll.

[ExcessiveBiker]

mpg octane

Has anyone actually tested the 750 against the 850 FD, or is this just unsubstantiated opinions?????? I have an 81SH with 66,000 total, and 40,000 plus with a 750 FD installed, that has been ridden severely, with no noises, metal in FD oil, or anything else to indicate an imminent failure. Has ANYONE broken a 750 or 850 FD, mounted on an 1100???????????????
Let the opinions fly.

ExcessiveBiker

[BA80]

The type 1 750 FD is actually the same as the type 2 750-850 FD the difference being the pinion depth and pinion bearing preload on the type 1 is a shimmed adjustment and the type 2 has a crush sleeve. The type 1 is very sensitive to the torque on the pinion nut, the type 2 not so much.

The type 1 FDs I've seen fail were, as far as I could see, improper pinion depth adjustment or over tightening of the pinion nut causing pinion bearing failure.

Has anyone killed a type 2?

My $.02

[skids]

Seeing that the 850 drive hasn't given anyone grief as opposed to the lighter duty 750 drive, I'll retract that opinion.
The Standard, stock final drive rpm's@ 75mph are 5K on my Venturer. Speedo is also dead-on checked with GPS. I know anything above 4K fuel consumption starts increasing..........but motor is so silky smooth at 5K, it's hard to resist just lettin' it roll.

Well, that is pretty standard rpm for that speed for standards...

[3Phase]

Hmm, the Type 1 and Type 2 '750 FD is 'weak' only compared to a '850 FD and the stock 1100 FD.

I killed the Type 2 '750 FD in my '80G but it took a lot to do it. It ran for, uh, I forget how many thousands of miles now but it died from wear and tear followed by lubrication failure. It was still running when I took it off the bike but it was definitely an ex-final drive, it wasn't just resting....

.