Interchanging luggage racks

[Gallaecus]

THE RACK ON THE TOP FITS 79 SPECIAL AND DOES NOT INTERFERE WITH SIGNAL
THE RACK ON THE BOTTOM FITS 79 SPECIAL BUT INTERFERES WITH SIGNALS.
NEITHER FIT 80-81 SPECIALS

STANDARDS ?????

DISTANCE BETWEEN SIDE HOLES ARE 6 1/8 CENTER TO CENTER
THE WIDTH IS 8 3/16" FOR BACK HOLES AND 9" FOR FRONT HOLES ON BOTH

[natemoen]

Bottom one looks like a standard.

[TheFrugalTech]

I have one of each of the same racks but one is busted.
I think I have it figured out. Someone please chime in if I am wrong.

78-81 Standards and 79 Special - Same racks, same measurements, interchangeable.
Rear mount below rack - Signals stay put.
Rear mount behind rack - Signals mount to license plate bar. Meant for use with tour pack and therefore purposely hides the original signal mounts.

80-81 Specials - Same racks, same measurements, wider at rear mounts, signals mount through the rear rack mounts. Any variations in the rear mounts???

If the above is true, I have a NOS sissy bar style backrest with scroll design for a 80-81 Special.

The rack I have with the mount behind the rack has a MUCH thicker mounting tab. The other I have broke the tab from the rack on one side and broke the rack itself about 3 inches back from the front mount on the other side. I had a trunk mounted to it that I probably overloaded too often. I'm hoping the good one I have is stronger.

Someone have the measurements for the 80-81 Special rack? We need a sticky post with the measurements and which bikes the racks interchange on.

[Gallaecus]

this is a type of rack that fits 80-81 specials
and has the sliding backrest.



it mounts to back of grab rail, where the stop light mounts.

[Gallaecus]

these racks fit 79 specials and standards

the one on top does not interfere with signals
the one on the bottom does interfere with signals




and they both use a back rest like this

[Gallaecus]

quotes from Crazy Steve

this is what Crazy Steve has in the interchange forum

All XS frames (and the XJ too) share the same basic architecture and design, but there's enough differences that swapping them is difficult. There's two basic XS 'types'; standard and special frames. While at a glance they can appear identical, they most definitely aren't the same. Things that are the same for both types are the neck, motor mounts, side and center stand mounts, swingarm, fuel tank, shock, seat and coil mounts. The XJ shares all this except for the seat and fuel tank rear mount, but there's enough 'other' differences that this frame won't interchange with any other. The two major differences in the standard and special frames are shown below...



Rear fender mount. Two styles, '80-81 Special at the top, Standards and '79 Special at the bottom. Completely different, this prevents swapping rear fenders between the two versions. The accessory mounting holes are also located slightly different (see arrows), so luggage rack and sissy bar interchange is affected; all standards and the '79 Special can swap bars/rack, but the later Specials need units designed specifically for them unless you mod them. Note that this late Special frame has been modified at the turn signal hole, normally this would look the same as the standard.