Porsche Boxster RTS (Roof Transport System) Roof Rack

A roof rack on a convertible car? Yes! There really is such a thing! The RTS roof rack (made only by Porsche) is unique and there's nothing else like it for any car! I get lots of looks from people as I drive by in my Boxster with the RTS and a bike or surfboard mounted on it, just like I used to get when my Boxster was new on this planet. Heck, I could have a bike and a surfboard mounted at the same time! And Porsche also sells snowboard and ski adapters, and a very nice cargo box. Some may question why a sports car should be used in this way. To this I say that it's my only car, and the fact that it allows me to take part in various sports that would otherwise be closed to me makes my Boxster the perfect car for me. I can autocross it one day, and use it to transport my bikes or surfboards the next. And always with style! I don't know of any other car that can do that, well, except for the Porsche 996-series 911.


The above pictures show my car with the RTS and bike adapter (on the left, with my Santa Cruz Heckler mountain bike), and with the Thule surfboard adapter (and my Advanced Surf Designs longboard at the famed Pleasure Point in Capitola south of Santa Cruz, a favorite longboard surf spot).

I bought my RTS used from a guy who bought it but never installed it. So the price was pretty reasonable. They don't show up on eBay very often, but I got mine locally for much less than I could have on eBay anyway. I couldn't find a used bike adapter, so I got one from Suncoast Porsche's on-line store. Pretty much your standard roof rack bike adapter, but very well built.

The Downsides:

The RTS is not without sacrifices though; it's expensive, not as easy to install as most racks, and it's noisy, very noisy, with the top down (or up!). Roof racks are always noisy though, so perhaps that's not a surprise to you. If you ride a mountain bike in the mud, be sure to close the top when transorting it! You can't operate the top with the RTS installed, which is another downside, and who wants mud dripping into their Boxster's interior? Ditto for wet surfboards as you don't want to make a habit of getting salt water inside your car's interior (I now wipe my board dry before mounting it on the rack). And did I mention the noise? Yes, it's noisy! I recommend closing the top before installing the rack to keep the noise down. Still noisy, but bearable (I still insist on lowering the top whenever possible, but I'm an open-air fanatic!). Someday I may try to fill up some of the casting voids and so forth with urethane foam to improve the aerodynamics, which might reduce the noise too.


Installation isn't super easy, but not too bad either. I find that the hard part is installing the permanent brackets onto the car; the rack itself then bolts onto these. But once you've installed those brackets (which you simply leave on) you'll find that mounting the rack and adapter, and your bike or surfboard, usually takes 15-30 minutes from start to finish (bikes take the longest to mount, surfboards and skis mount pretty quick), after you've had a little practice. Not too bad. When I used trunk-mounted bike racks I spent somewhat less time mounting the carrier, but then always had to stop after a few minutes of driving to snug down the attachment straps, so I'd say time isn't an issue. A trailer hitch receiver-mounted bike carrier would mount quicker though, as in maybe 5 minutes tops. But that doesn't work for surfboards or skis. Before attempting the RTS installation yourself I recommend visiting:

Skyler's RTS Installation Page

Technical Note: I haven't been able to find any torque specs for the RTS fasteners, and Porsche doesn't mention this in the instructions for the RTS. But, based on similar-sized fasteners that I do have specs for, I recommend 50-60 lbs/inch. So far this has worked fine.

In short, I probably would never have bought my RTS if I didn't get such a good deal on it, and if I didn't also need to carry a surfboard. If you just carry a bike I'd recommend going with a hitch-mounted bike rack.

Carrying a Surfboard the Cheap Way

I was recently faced with the need to transport a surf board that I bought all of a sudden. I couldn't get a Porsche surf board adapter from a dealer or by mail-order in time to avoid having the board get bought by somebody else, and the seller couldn't keep it in his tiny apartment (it was a 9'8" long board!). What to do?

I was simply going to strap it on my RTS as best I could, but decided to make a quick check for better options instead. I looked at the REI web-site, searched for "surf" and found two options, one from Thule, the other from Yakima. It was hard to tell from the small pictures, but it looked like the Thule adapter might fit with a little hand-work. Here's a link to it on REI's site:

REI's Thule Surfboard Adapters.

I then went to my local REI store and found the Thule surf board adapter in stock, and even the extra straps needed for carrying two boards! A quick look at the parts and I decided I could quite easily make it fit. I ran home with the kit (after paying), and figured out what mods would be needed and went to the hardware store.

There I bought a packet of M6 metric nuts, and a pack of 1/4" hole fender washers (about 1.5" dia.). I then filed the center holes of the fender washers square (to fit the carriage bolts from the Thule kit), and cut the washers flat on opposite sides so they'd slide into the RTS cross bars without rotating. I inserted the bolts into the washers, slipped them into the Thule brackets from the bottom (just as Thule intended, pretty much), and mounted the M6 nuts from above (the Thule wing nuts didn't have enough thread engagement for my peace of mind).

This worked beautifully!!! I picked up my new board, strapped it on my RTS, and drove home with it at a steady 65 MPH without any problems. And it only cost me about $45 instead of the $129 + shipping I'd have to pay Suncoast.


That board is a 9'8" longboard, so it seems that even a board that long does fit! Thule recommends keeping a maximum of 16" of the board ahead of the front adapter brackets, but I pushed it forward further in order to balance the board a bit better. I suspect Thule wants to limit the air catching under the nose of the board and pushing up on it, but I've had no troubles with this setup yet at speeds up to about 65 MPH and for several hundred miles of driving. Still, I'd definitely recommend keeping speeds down with this setup to avoid any damage to the board (or rack and car!). Like many surfers I mount the board backwards because the tail is narrower than the nose. A regular shortboard would catch less air, and the nose would extend forward less, so it would present less of a problem with aerodynamics. My other board is 7'2", so it's a much easier fit. By the way, I have carried both boards at the same time with no problems. The Thule adapter has provisions for a second pair of straps, so they just stack on top of each other.

Anyway, I hope this helps others looking for a cheaper, or non-Porsche, surf board adapter.

Using Yakima Bike Adapters on the Porsche Boxster RTS

I've now discovered that it is possible to get non-Porsche bike adapters to fit the RTS! I was at a local criterium when I spotted the only other RTS I remember ever seeing. The owner had found a simple way to use Yakima rack parts to hold his bikes. Here are some photos:


This person simply drilled holes in the bike mount wheel trays and probably used a carriage bolt setup similar to what I used for my Thule surfboard adapter above. It appears that there are several Yakima racks that could be adapted in this manner:

Yakima Bike Mounts from REI:

But, based on the pricing I saw on REI, it appears that this is no real cost savings over the Porsche RTS bike adapter. So I'm happy to have my Porsche adapter. But these Yakima mounts would be nice if you already have them from some other car, or if you prefer the fork-mount style of mount instead of the down-tube mount Porsche uses.

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