will sloted rotors from a 81 xs1100 specail work on 79 special xs1100?

[mrbsyammy]

will the front rotors from a 81 special (slotted)work on 79 xs1100 special??

[randy]

YES!

[Jerry]

The slotted rotors will work fine. There is a left and right side when you go to the slotted style, unlike the solid totors that can be used on either side. If I recall correctly, the end of the slot closest to the axle should be forward with the rest of the slot pointed back toward the bike.

[mrbsyammy]

well thank you very much

[TopCatGr58]

Hey Jerry, and Yammy,

Other knowledgable folks have posted about how it doesn't matter which slotted rotor goes on which side, that it's a cosmetic thing, that if the slot is going from closer to the axle outward with the forward rotation, or outward towards the center doesn't really affect it's performance.

My thoughts were, though, with regards to water shedding from the slots, but again, I can't see any problem with that either!
T.C.

[Jerry]

Wondered about that. However, the parts manual does distinguish left and right side, different part numbers, for the slotted rotors. It may be to distinguish them from the rear slotted rotor, which has a different offset and is not interchangeable with the front rotors. On a 3-rotor set-up, using slotted rotors, putting the axle end of the slot toward the front will make all the slots in all 3 rotors match, just a cosmetic detail that only pertains the the '81 XS and '82 XJs that came with slotted rotors.

[randy]

The '80 and '81 slotted rotors are stamped near the center to identify left and right. The two right rotors (front and rear ) are the exactly the same.

[Jerry]

The rear rotor on the XJ carries a different part number than the right front, is also a 10M number which indicates it is was first used on the XJ. All 3 (from XJ fiche) are:

Front left: 3H5-25831-10-00
Front right: 3H5-25831-00-00
Rear: 10M-25831-50-00

Are you sure the right front and rear rotors are interchangeable on an XJ? Would be great, since I could use one of my spare rotors on the rear if ever needed. I was under the impression - could be wrong! - that the XJ rear rotor had a different offset than the fronts.

Checked the EBC web page and they show a different number for rear XJ rotor than the fronts:

3H5-25831, both variations, = EBC #MD2024
10M-25832 = EBC #MD2025

[mrbsyammy]

I am all confused with your reply no one was talking about rear rotors or XJ????

[Geezer]

The only difference in the rotors is the direction of the slots. You can put the left one on the right and the other way round or have 2 lefts or 2 rights and the worse that will happen is it will look strange.

I have a couple sets of solid rotors that I plan to drill for my 2 XS11's if I ever get around to it. I have a nice drill press and the right bits but with my luck I'll drill the holes out of pattern and it'll look weird.

Geezer

[Dennyz]

with my luck I'll drill the holes out of pattern and it'll look weird.

It is all in the jig.

Take a piece of sheet aluminum or steel and create a drill guide. I cut out a round block of wood from a 2x4 that fits in the rotors center hole. I created my pattern from the center of the block. I rotate the drill guide around the rotor, pivoting on that center. I use the mounting bolt holes as indexes. Marking (punching) each set of holes, then move the guide to the next index hole and punch away. I noticed on each rotor, there is a mounting hole the matches up with the trapezoid holes stamped in the rotor. That is where I start.

With this technique I get a right and left set of rotors that match (the holes line up).