final drive mod...

[TomRodgers]

What exactly is this modification......have seen it mentioned several times, but have no clue as to what it is.......

[kjohnson]

It is the process of modifying the final drive from an XS750/XS850 to fit the XS/XJ1100 with the intent of either better fuel economy and/or greater top speed.

details here : http://www.xs11.com/xs11-info/tech-t...-6th-gear.html

[XJOK2PLAY]

Yes, KJohnson is correct. Only thing I might add to help you understand would be the 750-850 FD's are taller geared than the 1100 FD. So RPM's drop somewhere around 800 rpm less once the swap's done. (It's almost like adding a 6th gear to the tranny.)

Some say they see improvements in MPG, others say they don't... but almost all say they're glad they did the swap.

It was thought up by a fellow member here... XSChop, then broken down and explained in detail by another member, Maximan.

Best of luck in your endeavours...
Bob

[trbig]

My reason for doing it was neither of those. Though better fuel mileage would have been nice.. I didn't get any better. What I did get that I wanted was a drop of @ 800 rpm at cruising speeds of @ 70mph. The bike always seemed like it was winding up too high for me and I was constantly trying to up-shift into another gear even though I was already in 5th.

Tod

[randy]

I found with the swap, that I get the best mileage if I avoid 5th gear as much as possible. Of course, in the straights on slabs 70mph in 5th is about my average cruising speed. But between 50mph and 70mph I avoid 5th and the mileage jumps up. The engine seems to like the 4500-5500 rpm range, it just breathes better I guess. Some techno-guru here will probably have a long-winded explanation with charts and graphs and 8X10 glossys with writing on the back to expalin each one, and maybe even a dyno chart, but all I know is it works for me. YMMV.

[Pat Kelly]

The carbs transition from pilot jets to main jet around 4200 RPM (about halfway to redline)

[MindWebs]

ok...

Just to throw a silly question in the mix.
the standards and the specials have the same final drive assembly... right?

so this procedure would be the same on my special.

Thank.

Webs

[MindWebs]

wow... that post was poorly written!!!

lets try this again...

why are we swapping out the entire housing?
are the ring and pinion different(other then gear ratio).

it just seems more prudent to swap out the gears like you would on any other vehicle.
BUT!!, I've never torn down the drive on this bike to see how complicated the guts are.

if someone know the answer please let me know

Thanks.

Webs

[stoked]

I did my special and used a generic 750 rear with no problems. The one thing I woudl pay attention to is the pinion nut. It's been a couple of years since I did it but I recall removing it to put the washer in to block off the hole the 750 uses for lubrication and the 11 does not. I do beleive it does matter how much you tightent that nut back down. I also beleive the manual covers that. But i recall someone in one of the early conversions did not tighten it adequately and it ended up coming loose and lost a tooth or two on the gear. I'm not sure on these bikes but overtightening a nut on a pinion shaft can cause issues also do to gear alignment.

Or I could be totally full of ****. But I've probably put 15000 miles on mine since then and love it. I honestly can't say if the mpg is better or not at this point, the coil change seams to of been better for that, but being able to leisurely cruise anywhere from 70 to 90 mph without the bike sounding like it's all the way wrapped out is great.

[red bandit]

why are we swapping out the entire housing?
are the ring and pinion different(other then gear ratio).

it just seems more prudent to swap out the gears like you would on any other vehicle.

It's a lot less work to just swap out the entire housing. The gears would probably swap, I don't know for sure, but why tear apart two housings when you don't need to.

[DGXSER]

IMHO Red Bandit has it. The housings are identical in size shape, layout....etc. And in order to tear one down, it has to be completely removed from the bike. To use the 750 drive, you simply remove the pinion nut, add sealant and washer, replace nut properly torqued, add a spacer to the drive shaft, install.

Seems ALOT simpler than tearing down the drives and swapping gears around. And honestly that would be out of the comfort zone at least for alot of folks, again, IMHO.

[oseaghdha]

lets try this again...

why are we swapping out the entire housing?
are the ring and pinion different(other then gear ratio).

it just seems more prudent to swap out the gears like you would on any other vehicle.
BUT!!, I've never torn down the drive on this bike to see how complicated the guts are.

if someone know the answer please let me know

Thanks.

Webs

I know enough about setting gears up to know I don't like to do it for fun.
The gears are custom fit to the housing, and each other, with different shims. Engagement, backlash, preload all need to be set. By using the entire housing, you don't need to fuss with it. Almost plug-n-play. I could switch it back in an hour an go to the drag strip, or something.

Besides which, you aren't going to find just the gears. You'll end up buying the whole unit anyway.

[DiverRay]

And, IIRC, the gears will NOT swap between housings! You also have the problem with the spline difference between the 750/850 and the XS1100 pinion shaft. That is why you need to block the two oil holes in the 750 FD, as the 1100 coupler will NOT fit.
The swap is a great thing for the bike, but I notice I drop to 4th a lot more to pass going up hill.

[Poprock]

I'm running a 850 drive in hilly, twisty slow-driving country. Pulling 48 mpg on liesurely cruises through the coast range. 4th gear now produces the same rpms at 60 as 5th gear used to. 5th gear dropped to 3450 from 4000. It is like an extra top gear. Strangely enough, although 1st gear is taller, it's no problem for the bike. Bolt on and GO!