xs1100 turning into a trike

[DCracer25]

I post some pics later as I get into the build. But here goes I bought a non running 81 xs1100 a month ago got it running seems to run good, so I started to take the bags and rear fender off, rear wheel will be next, btw does anyone know which way the drive turns? Pick up complete rear end with brakes and emergency brake setup. I will have some parts up for sale as I go into the trike build. such as complete rear fender and lights and turn signals, rear wheel and hub and disc brake setup, not sure if I am going to sell the bags and crome bars that go around them, may even swap some parts for other stuff I need. will let everyone know what I need.

[TopCatGr58]

The Driveshaft turns CCW as you are looking at the rear wheel from in front of it. See this exploded view of the driveshaft/final drive.

http://www.yamaha-motor.com/partview...XS1100H_-_1981)

This CCW direction is opposite of most automotive rear wheel differentials, and what I've read about Triking is that folks end up getting a small rear end off of a small car and then flip the thing over, left wheel to right side and vice versa, essentially you're driving the rear end in it's native REVERSE direction ALL the time. Good Luck with the build.

T.C.

[CaptonZap]

This CCW direction is opposite of most automotive rear wheel differentials, and what I've read about Triking is that folks end up getting a small rear end off of a small car and then flip the thing over, left wheel to right side and vice versa, essentially you're driving the rear end in it's native REVERSE direction ALL the time. Good Luck with the build.

T.C.

And that can lead to problems with the brake cylinders.
Unless the backing plate bolt holes are are spaced so that they can be replaced on the appropriate side, right sideup, the bleed screws are pointed down, which makes it hard to bleed them. JAT CZ

[TopCatGr58]

Here's the thread which has a few links you may find helpful as well.

http://www.xs11.com/forum/showthread...=trike+rearend

[DCracer25]

trike build

Thanks for the info, the rear end I got is from a small 71 plymouth cricket AKA ( hillman) in the UK that looks like a small ford mustang rear, and yes I can flip it and the brakes will work on the oposite sides. just got the rear all apart to clean it up. got everything from brakes to em brake cable and handle so my wife can use it when she parks the bike. I cut off most of the mounting brackets to smooth the rear. then use my own brackets to mount the rear on the bike. Not sure on how much I will shorten the axles and housing yet because the housing from backing plate to plate was only 50 inches wide. I know for sure will have to shorten one side to line it up to the bikes driveshaft. So any info you guys might have would be appreciated. thanks again.

[crazy steve]

One thing you may need to be careful of is how much 'hypoid' the rear axle has. If it's a straight bevel gear set (like the XS), turning it over won't matter. But if it's a hypoid design (and most are), that may raise the pinion gear (and it's bearings) out of their lube 'bath' and you may have issues with poor lubrication to the pinion bearings. You'll have to look to see where your fill point is in relation to the bearings. And overfilling it may not work either; generally, the axle seals aren't designed to have a lot of fluid against them all of the time, so you may have leaking issues.

[cywelchjr]

One thing some guys do is put a gearbox in the middle to reverse the rotation of the shaft so they don't have to turn the axle over. Then the axle runs the way it was designed and all those other problems go away. Now I don't know what it takes to make one of those gear boxes to reverse the shaft rotation, but I know there's more than one guy over there in the UK that has built a trike and done just that.

[CaptonZap]

It's a shame that the VW Bugs are not as numerous as they once were. The trans axle could be configured for either CW or CCW rotation of the input shaft by flipping the ring gear. Then, with some clever linkage, you could have 20 forward gears, and 5 reverse!
One other thing to watch is that the MC frame was not designed to resist rotating forces front to back, and you will have some with a wide rear end. (Not your wifes, the bikes. ) CZ

[crazy steve]

One other thing to think about is gear ratio; most small cars have pretty low final drive numbers (3.50 or lower), so that's going to eat into your top end pretty badly.... but will make for easy wheelies

Yeah, a VW transaxle would be the hot ticket. You could gut the trans internals out (reducing the weight a bunch), but you'd still have that 4:10 gear ratio....

[natemoen]

Anyone know off hand what the final drive gear ratio is on the XS11 or on the 750 FD?

[DCracer25]

trike build

the fill point is in the center of the rear cover on the rear end, has a 10 bolt rear cover. as for ratio will clean up gears to find out what they are. will try and get some pics today and put on here.

[Mr.Bill]

Might be a nice rear if geared correctly, or if the gear change is readily available for that.

I had heard a rear from a small 2wd pickup is a good find and plentiful, Usually a bit shorter and most cases a 4:11 rear set.

I would not worry a whole lot about shortning the rear to line up the drive shaft, as you want some angle anyway to avoid the U joint from wearing.

Just use a u joint at the middle drive and at the rear and cut a shaft to fit.

[CaptonZap]

Anyone know off hand what the final drive gear ratio is on the XS11 or on the 750 FD?

The 750/850 is about 2.9, and the 11 is about 3.3.
These numbers were calculated by counting the input sleeve revolutions and comparing that to the hub spline revolutions and extropolating the relative positions observed, thus no claim as to accuracy will be made, and all use of these numbers is at the users discrection, with no liability assumed by the author, the publisher, or their heirs or ensigns. CZ

[DCracer25]

trike build

Ok the camera is in for repairs. But the rear end ratio on the rear I got is 3.89 and the way I figure it with 15 inch tires and rims should put me in the ball park. What I need to figure out now is what model 81 xs1100 I have. I took the no.s off the vin tag JYA4R100 XBA002153 then engine no.s 4R1-002103 My Book on it tells me it could be a g or h model then it says there are more models, Also I was told it is the 1st generation venture model if I got that right. because it has the full dress fairing and bags and trunk. Been doing alot of research on rake and trail. Also if I increase the wheel base alittle bit will it make it better or worse? As it sets now its 60.5 inch long. Maybe increase it by 6 inches or so.

[crazy steve]

...the rear end ratio on the rear I got is 3.89 and the way I figure it with 15 inch tires and rims should put me in the ball park...

That's pretty low... you'll need a 30" tall tire to get back to the stock 3.3:1 XS gearing (like a 255/75-15, a truck size) if you don't want the motor buzzing bad at highway speeds.

Your serial numbers shows that as a '81H model, AKA a 'Venturer'; the full-dress 'standard' model for '81.

Trail you'll want to reduce for a trike for lower steering effort. Adding to wheelbase won't effect handling much, but will make the bike less manueverable in close quarters.