Prius + Bike Rack Page

Mounting a Trailer Hitch and Bike Rack
on a 2006 Toyota Prius

page created by Harold Marcuse
August 4, 2007; updated 1/2010; 7/2013

Harold's personal homepage, Los Padres bike trip page
see also my UCSB Faculty homepage

Background (back to top)

• July 2013: Mike Thomas's infographic on how to choose the perfect bike rack added below.
• Jan. 13, 2010 breaking news: At the auto show Toyota announced that it is going to make Prius a "line" of cars, with a subcompact coming out in 2012. See this Los Angeles Times article, "Toyota plans to turn Prius into a sub-brand."

I am an avid bicyclist, and wanted to do some bicycle touring that required driving to the starting point of a bicycle-camping trip. Thus in June 2007 I started researching how to mount a bicycle carrier on my 2006 Toyota Prius. (My bike's fork length is just enough that I have to remove the front wheel to fit the bike inside the car, which then takes up most of the room in back, and can't accommodate a second bicycle.)

Thus my first hurdle was to figure out how best to mount a couple of bikes on a Prius. There are basically two options:

• a trunk-mounted carrier (like the Saris Bones--photo at right; cheaper models by Allen or Bell or Thule) that straps on to the back hatch, but you can't open the hatchback with it on. For camping, as well as for bike set-up upon arrival for day trips, I decided I wanted something that allows unhindered access to the trunk.
• a trailer-hitch-mounted carrier, of which there are many varieties. I decided on this option, even though Toyota recommends against using a Prius for towing. After all, a couple of suspended bicycles are nothing like towing a trailer, and numerous Prius owners displayed their hitches and light-weight tow vehicles on the web. (There are 1 1/4" Class I hitches for light weights, and 2" hitches for heavier towing. The size refers to the square hole--"receiver," into which you fit a ball for a trailer, or your bike rack's pole.) The next step was to get a trailer hitch on my Prius.

Trailer Hitch for Prius (back to top)

From various web sites I learned that I could get a Curt company custom trailer hitch for Prius ($129+$25 shipping from etrailer.com in Wisconsin; $185 at hitch-web.com). The discussions on the web made this one seem better than the $149 hitch by CoastalETech in Florida, which had bent under the load of 4 bikes (see PriusChat hitch discussion with photos). The ETech one is also more expensive.

Ordered Wed. June 19, my etrailer hitch shipped on Wed. June 27 and arrived in California on Tue. July 3. (I think they manufacture on order, as this is a custom designed product.) Ok, now to get it onto the car.

You may not know it, but Priuses have two "tow hooks" mounted on the underside of the chassis. The Curt hitch is designed to use the same screw sockets. Someone on the web wrote that they had their hitch installed (by U-haul) for $99, but others had written that they did it themselves without a problem (see EV nut's Curt Hitch page). I like to do such projects myself, so I decided I'd give it a try. I found I'd need a torque wrench and a metric socket set. None of my neighbors had any to borrow, so I decided to see whether I could get them for less than the $99 I'd pay to have it mounted for me. I picked up a simple 1/2" drive torque wrench ($35) and a 1/2" socket set ($10) at K-Mart (you need a 17mm socket to get the original tow hitches off, and 19mm to put the Curt hitch on), and got the job done in less than an hour with some help and moral support from my son. (Note: I later bought a simple 1/2" drive ratchet handle for $10 at Sears to make it easier to bolt the bike rack into the hitch receiver--the tool at bottom in the photo. That would have made mounting the hitch--screwing in the bolts--even easier.)

I put an old rug down under the back of the car, which I didn't have to jack up--just left it in the garage on the floor. Slide under and have a look.

I didn't take any pictures before I mounted the hitch--so this is a staged photo afterwards.

Steps/Difficulties we encountered (for additional info and pictures, see EV Nut's page about how he mounted his Curt hitch to his Prius--he's much more of a do-it-yourselfer than I am).

1. Getting the fascia (plastic panels attached to the underside of the car with plastic fasteners) off on the driver's side. To get the plastic rivets out, you pull the central head out a little way, which allows the tip on the inside to slim down, and then pull the whole thing out. (This may not make sense now, but when you're under your car it should help.)
2. Unbolting the tow hooks. They're on pretty tight. I put the 17mm socket onto the long torque wrench to loosen them, then unscrewed them by hand.
3. Cutting the driver's side fascia--see photo at right (the out-of-focus line down the center is the hitch flange; the wedge-shaped gap to its right is my slanted cut). Not hard, really, but I didn't do a very neat job of it. Cut too much on one side, and had to widen the cut so that it lined up with the flange. I used a heavy duty shears. Maybe you could get a straighter cut with a razor knife.
4. Bending the mounting flanges on the hitch so that they line up with the bolt holes. After loosely attaching one side, it was clear that I needed about an inch more width to align the other side. EV nut said he had banged it against a tree, so I tried that. Worked perfectly. I banged a tad too far the first time, but one bang back was all it needed.
5. Mounting the hitch. My son held it in place while I got the bolts started. The hitch weighs 30 lbs, which I confirmed on a bathroom scale.
6. Torque the bolts ("M10 fasteners") with their conical washers (hollow side towards car) to 35 lb-ft. No problem with my new torque wrench.
7. I needed to recut the fascia before I could get those plastic rivets to line up again--see 3, above.
8. Done!

View of Curt hitch mounted on 2006 Prius; below details the modification made after EV nut's problem.

Rear Height Clearance issue: Here in sunny southern California we don't have many underground runoff sewers. Instead, there are dips across the road at intersections, which channel the water across the streets during brief and infrequent but heavy rainstorms. The front spoiler of my Prius gives the deeper ones of these a scrape if I'm going too fast. How about the flanges of the Curt hitch?

I never had a problem with a moderately loaded car with 2 bikes on the back, nor under normal daily driving circumstances. However, recently I had 4 people in the car and a lot of stuff in the back, and the hitch did scrape on one of those dips (I was going a bit fast to be sure I made a traffic light). As you can see from the photo above, the rear clearance is a bit less with the hitch on.

The Hitch-Mounted Bike Carrier/Rack (back to top)(more Photos below)

• After I decided on a hitch mount, I started looking at bike racks. Since my daughter's bike has a slanted tube, I pretty quickly decided against the models that hang the bikes from the top tube. (I also could not see what would keep them from swaying in and out, and the opening-the-trunk-with-bikes-mounted problem seemed worse with them.)
• I didn't want a roof mount, both because of air resistance, and because I'd worry about going into a garage or parking structure forgetting that the bikes were up there (with rear mounts you have to be more careful upon backing up, but your bikes are always in view).
• I also wanted the convenience of not having to disassemble the bike, not even taking off the front wheel (my mountain bike has drop-out locks, so you have to unscrew the quick release axle all the way), so I didn't want the kind that uses the front fork to secure the bike.
• I ultimately decided to go with a "flatbed" model that has loops (or a kind of tray) that you set the bike wheels into, with another device to hold the top of the bike in place.
• There are various models like this. I started with the top-of-the-line Thule brand T2 ($325 from RackCity), but then was adding locks at $35+$20 for cylinders to protect my purchase from being stolen off of my car, and decided that I didn't need to spend that much money on something I wouldn't be using all that much.
• I looked at a Hollywood HR1000, $189 at amazon, Swagman XC Cross-Country, $190 at amazon (only for 2" hitch), but didn't like them as much. The most expensive was the Saris Cycle-On pro, $430 at RackCity.
• I ultimately bought an XPort Flatbed lr 2-bike model (at that time on sale for $150+$36 shipping from BikeNashbar.com [but not on their web site at the time]; $180 at RackCity).
• Pros:
  • folds up from the sides to the center when no bikes are on it
  • leans away from the car in case the handlebars keep the trunk from opening all the way
  • easy to lift bikes on, very stable/no sway.
  • much lighter (and cheaper) than the Thule (and others).
• Cons:
• uses a padded hook to pull down on the top tube to secure the bike. Thule uses a swinging ratchet that holds the front tire. Thule's can't damage the top tube, and will work with bikes without standard top tubes. (Will it work on a bike with a front fender?) I have brake and derailleur cables running on top of the top tube, but the padded hook didn't make any scratches.
• you may have to adjust the wheel trays for different bikes, depending on how long their wheelbases are.
• Neutral: need for locks
• It is easy to use a regular cable lock to lock one or two bikes to the loops on either side of the hitch receiver, which are welded on. That way, both the rack and the bicycles are secured from theft.

Potential Clearance & gas mileage issues:

• The two bicycles that I've put on the rack are a bit wider than the back of the car. (Prius bumper ca. 62 inches wide; my road & mountain bikes 68-69"); see photo above. The Prius "bulges" in the middle, however, so the bikes are narrower than the widest point of the car. Still, bikes on the back do stick out a little. Not that that is a big issue, just something to be aware of if you like to squeeze between tight spaces.
• I didn't drive far enough with the bikes on the back to be able to tell how the aerodynamics with the bicycles might have affected gas mileage. Since the bikes are mostly in the turbulence wake, I doubt the effect would be very great.
• By the way, I notice no drop in gas mileage that might be due to the additional 30 lb. hitch I'm lugging around all the time now. I do notice, however, that mileage drops when I have heavy passengers in the car--about 5 mpg less for 500 lbs. of people besides myself.

Photos(back to top)

Xport bike rack, open

Pull out a pin, and the rack leans back to allow better access to trunk.

If you don't have bikes on it, the rack folds up to be more out of the way.

Instruction sheet for mounting the hitch: click for full illustrated version

Click on this image to get the full, illustrated sheet of instructions

Links (back to top)

• My Bike Trip through Los Padres National Forest Page--in July 2007 I did a loop from Santa Barbara to Ojai, California. (My first use of the Prius+rack, when a friend met me.)
• EV nut's Curt Hitch page is by far the most detailed on this issue, although it is a bit dated now (Curt improved their design on his suggestion), and he is much more of a do-it-yourselfer than many of his readers are apt to be.
• PlusAF's Prius page has links to some photos of his Coastal Etech hitch--you can see how the longer torque arm makes it more apt to bend down under the weight of bicycles--he uses it for towing. He scanned an excellent column that explains the Hybrid Synergy technology very clearly.
• John1701's Prius rack page -- he had a custom hitch welded for his 2000 Prius in 2001. Click on the green Prius icon in the bottom corner to go to his main page--he has LOTS of data about his old and new Priuses.
• Bird Automotive's 1" pipe mounted Prius rack is an innovative idea--it doesn't need a heavy trailer hitch, but with an hour for installation it may not be as simple as it looks. And the price is pretty high: $369.
• Autoanything.com's Prius page lists lots of accessories, including many racks you can use with the Prius.
• Priuschat.com has a number of relevant threads (use the search feature for more):
  • various photos, from June 2007.
  • photos of 1upUSA hitch-mount rack and Yakima roof rack on Prius
  • photos of broken Coastal hitch
  • is it good to use a Prius to tow (heavy) things? (pretty long-winded chatters!)
• 2003 thread on bikeforums.net discusses roof racks and the Saris bones.