750 final drive swap questions

[BossMaverick]

Last night I bought a 750 final drive with shaft off ebay. I normally ride at 65+ so I can't wait to try getting the taller gear in but I have a couple questions. If I take the oil seal off the xs750 shaft, could I use that instead of the spacer on the xs1100 shaft? Also (if I do have to use the 1100 shaft), has anyone had any luck finding a supplier of that rocker arm bushing that is mentioned in the how-to article?

Thanks!

[randy]

First question - no, BTDT, the shafts are not the same length. Second question - don't know, I used a 3/4" sweat fitting trimmed to length. I believe the supply house for those bushings was listed in the thread. Look a little more.

[bikerphil]

I used a bronze bushing from Ace Hardware on both of mine. It has to be cut down to 16MM length though. They are about $3 each, and are pretty stout.

[randy]

Something I've wondered to myself these past three years with the 750 mod (which I LOVE, by the way), Why not just swap the gear coupling from the 11 onto the 750 drive, that way we don't need a sleeve on the 11's drive shaft?

[BossMaverick]

After a few calls I found a semi-local oil field supplier/servicer that was able to order the shaft bushing for me. It seems to be an odd part for around here so I'm guessing the 346 engine isn't used in this oil field. The bushing will cost me a whopping $1.50.

[xschop]

[QUOTE=randy; Why not just swap the gear coupling from the 11 onto the 750 drive, that way we don't need a sleeve on the 11's drive shaft?[/QUOTE]

Won't interchange without a 20# sledgehammer....the pinion splines are actually different between the 750/850 and 1100. I tried that route

[dbeardslee]

Seems to me if you had the complete swing arm assembly off a 750 you could just swap the whole thing without modification - something my brother and I are going to try later this summer. On the spacer, it doesn't really do much, nor is it subjected to much force as it just spins with the drive shaft and u-joint. If a spring can hold it in place on one end, you'd think the copper would be enough on the other (famous last words ). I just used the copper spacer on mine, and it seems to be doing the job fine. Which ever way you decide to do it, get ready for a whole new machine on the highway - definitely the bomb mod. And for those who think it doesn't affect gas mileage, I cracked 44 mpg with it - the most ever.

[xschop]

Swappin' Swingers'

The Xs750 swingarm is shorter by 1.5" IIRC. I never mic'd one out to determine wheel centerline for the 750/850 like I did for the XS11 and the ZRX swingarm/wheels....FYI

I have a close to factory FD ratio of 3.23 (13T front, 42T rear) as of now and will be swapping my new 14T front sprocket on this next week for a perfect 3:1 ratio, because I miss the better gas mileage and lower Hiway RPMs that I got with the 750FD mod before I went chain....

[Ivan]

I can pull 44 mpg with my 750FD, but I have to ride like someone's ailing grandmother. Anytime I get above 70 mph, the mileage slips. Out here in the vast expanses of the great plains, 80 mph is a steady cruise, and if you want to push it, 85. If you do the 70 posted limit, your ancestry will be cursed.

I am guessing that there arw other contributing factors to the higher mileage than the higher gears, or I would be pulling high numbers as well.

Gotta admit though, there is no feeling like passing a gazillion dollar Harley at 120 and shifting into 5th just as you pass.

[randy]

Gotta love that 750FD. During our recent XSEast rally, We stuck very close to the speed limit on back roads and one day I got near 50 mpg! I still don't believe it, but the gas pump don't lie!

[DGXSER]

Pumps don't lie, but I often wonder if my tripometer and speedo do. I can not believe the number of times I am on my bike riding at the posted limit and passing by everything in site. I know people around here are not that timid or law abiding that they are all going at or below the limit. So, if my speed is off, thne my miles could/would be off also, making my milage calcs inacurate.

[randy]

No, I think these bikes don't like to go slow Your OD might be off, though. Try comparing it to an identical car trip.

[Ivan]

FWIW, my speedo is off by 10 at 70. Meaning I have to run 80 to see 70 actual.

My odometer is almost dead nuts on. I ride 100 miles and my odo will only be off by .2 I fiigure that is just differences between linear distance measured by the wheel, and the points plotted by the gps that are used to figure the distance.

[randy]

I have to run 80 to see 70 actual

You see, they really don't like to go slow, officer!

[Ivan]

whats really bad is 70 is slow for me.