http://www.beemershop.com/Merchant5/merchant.mvc?Store_Code=BS&Screen=PROD&Product_Code=TRA54063The Ei driveshaft has been very popular with the R100GS riders where failure is more of a problem. Ei also has a K75/K100 driveshaft which is less known because as a general rule we don't have u-joint failures on the K models like we do on the R100GS (only spline failures typically). But it has all the features and benefits that the R100GS driveshaft is known for such as:
All parts are available separately so if you were to have a u-joint failure at some point (unlikely) you could buy just the front part and a u-joint kit for example. With a BMW shaft you have to throw it away and start over even if you only need the spline or just a knuckle for example.
The u-joints are larger than stock, very heavy duty German joints made by Elbe with grease fittings so they can be serviced.
Specific to the K model driveshaft, a closed grease canal so the female spline can be packed with grease and it will stay put unlike the factory shaft where the grease just migrates out of the spline.
These shafts are sold around the world by other BMW specialists in Australia, Germany, England and elsewhere and have withstood the test of time with proven reliability.
They are less expensive than a BMW shaft, and rebuildable so in our view it's a no brainer that this shaft is the better choice.
