Thanks for this advice.The bottom tube clamp fits up to 3 and 3/8" and the Rail's tube is at that or slightly more. Also, you're pushing the weight limit of the 598 as well. It will hold 20kg which is pretty much the weight of the Rail without the battery. In other words you are pushing all the limits of the rack and I wouldn't put a bike this expensive on a rack without a margin of error.
You don't say what type of vehicle you have, but hitch mount would always be preferable.
I had an M235i so I hear you (now have an RS3, same issue ... but I just use my wife's Q3 with a hitch mount).Thanks for this advice.
I have a BMW 2 Series, hence the need for a roof mounted.
Have you any experience with the front wheel rack, Thule 599?
Thanks very much for your advice!
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