Saris Bones Bike Rack Mod

Following the recommendations in this thread, I got a Saris Bones trunk mount bike rack for my Gen II Prius:
http://priuschat.com/threads/bike-rack-for-2007-prius.49255

The trunk rack works well and, when properly installed, does not damage the paint. However, unlike some of the commenters, I found it it a pain to put on. I don't have a garage - it lives under my porch. It is big and bulky to carry, with 6 straps whose metal hooks bang against my trunk as I put it on. It's awkward to hold the thing while I attach the top hooks and I have to open and close the trunk repeatedly to attach the side hooks. Then I have to go back and forth tightening the top straps against the bottom ones, so that it won't pull off under weight, but isn't pulled off the bumper either.

So I decided just to leave the thing on the car. Well, the Prius already has bad rear visibility; with the rack in the window it's even worse. And the wiper can't be used, so when it rains it is truly terrible.


I thought about this a lot during the last week of rain, and realized that if the legs we just moved further out it would be much better. So I did this by remounting the legs on a new tube that runs the full width of the trunk.

(I also shortened the arms, as I just have one bike.)


Here's a view from the inside - I don't have a before picture, but maybe someone with a Bones can post one:


The bottom pane of the window still has the side straps in the way (in a later photo below, I've moved them out of the way). But the top pane is much more important for visibility. You'll also notice that you don't see the center post at all. I raised the height of the rack so that the center post is positioned directly behind the rear spoiler. When not carrying a bike, I also position the arms to minimize their visual obstruction (which you can do without modding).

Rather than bolting the legs and arms directly onto the new tube, I decided to use the original mounting system, which allows the arms and legs to be adjusted and distributes the weight evenly between the plastic and the tube. I did this by cutting the original tube into three and bolting it along the new tube.



I did bolt through the outer legs, as I otherwise would have needed to dedicate more of the original tube just for a bolt, and I didn't want to take any more of that away from the center arms (Or I could have cut the original tube into four pieces, arranged differently, but this was more work). The 3/8" nut in the legs is very conducive to bolting, and the other arms and legs can still be adjusted relative to the outer ones.

The straps had to be rerouted, as it was now too wide for them to exit from the ends of the tube. I separated that six-headed buckle into three and tied each around the pole, one in the center for the side straps (which I have since hung off the tip of a 8" bolt to get out of the way of the bottom pane of the rear window - see pic. below), and one on each end for the top and bottom straps. Attaching the side straps to the ends of the tube would make too sharp an angle.

Concerning raising the rack so that the center tube is directly behind the rear spoiler: You can't do this with a stock Saris Bones because the bottom legs aren't long enough to still rest on the bumper (I've seen cars where the bottom legs rest on the trunk - a no-no:

With the wider tube, I was able to position the bottom legs where the bumper slopes up. The feet point to the door rather than down. The contact still isn't great, so I may make a shim to attach to the feet.

The new tube is aluminum, 42.5" long, 2.25" OD. I used 0.125" wall thickness, though that was probably overkill and it weighs over 3 pounds. Another option would have been to buy a second center tube and attach them together. They weigh under a pound and are only $20 from Saris. Indeed, were I to do this again, I would get a second tube from Saris, as it wouldn't be as heavy - the Bones makes it hard to open the trunk, even more so with an extra 5 lbs of metal.

I used 3/8" stainless steel bolts, which are much stronger than necessary but fit the existing nuts in the legs - 4" on the ends and 2.5" in the middle. Aligning the holes on the ends with each other was a little tricky. In addition to drilling a hole in the outside legs opposite the nut, you also have to enlarge the hole under the nut (the tip of the plastic set screw is less than 3/8").


UPDATE

I put a 3/8" x 8" bolt through the middle of the tube to hang the side straps off of:




I also replaced the 16" rear wiper with a longer one - it can take up to 24" before it hits the spritzer (use a front wiper - they don't make rear wipers longer than 16").


UPDATE

One problem with leaving the rack on the car is that the added weight makes it hard to open the hatch. I bought replacement struts that were stronger. Switching just one almost brought the hatch back to normal (with the rack on) - it's easy enough to open, but doesn't open on its own. But switching both would have made the hatch too hard to close without the rack. Doing it again, I would try to reduce the weight:
- Use a second Saris tube, which is lighter, or some other thin-walled tube
- Use shorter bolts that only cross one wall of the tube, or perhaps with smaller diameters.

 

Thanks.

Well, others do say that it's easy to put on - with practice you certainly could get your system down. But the more serious bikers I think do resort to roof or hitch carriers.