Vintage BMW Motorcycle Owners

I am converting my 75 90/6 to dual discs. Put everything together last night, with the left caliper going in nicely. When it came to the right side, the hole in the caliper would not line up with the holes in the slider. My first inclination is to shim behind the disc on the right side. Alternatively I could slightly increase the axle spacer, but that may throw off the left side.

I measured the space between the outside face of the disc, and the top "arm" on the slider at the closet point. Left side is 1.3mm and the right is 2.25mm. To shim out the right side will take one or possibly two washers, or bmw part # 34111232417.

All advice would be appreciated.

thank you

Welcome to the forum! Not sure I'm visualizing things but has one slider slid down more than the other? With the fender and internal brace removed, each slider can move independent of each other.

Kurt,

thank you, glad to be a member. Sliders are fine, and even with each other. My issue is with the horizontal spacing. Simply, the left disc is closer to the left fork slider than the right disc to the right slider.

So one of the disks can't slide into the caliper between the pads? I would think they should fit. The left disk is the original while the right side has been replaced. What was the source of the right side parts? According to RealOEM, there is a R90/6 retrofit kit:

https://www.realoem.com/bmw/enUS/showpa ... Id=34_0607

According to RealOEM, those "washers" 34111232417 are only used up to 9/1974. Seems like you shouldn't use them at all.