Best Low-Cost DIY Bike Mount for Your Car - Kuat Dirtbag
Kuat makes the best bike racks on the market (in my humble and Springfield, Missouri opinion) and I have been wanting to purchase a Kuat NV rack since they first came out: Products » The NV | Küat Unfortunately, my car does not have a trailer hitch, so adding in the cost of the hitch, the bike rack was out of my price range.
I have a 2001 Volvo XC70 Wagon and the original owner had factory roof cross bars installed. Until last week, I was laying down the back seat and fitting my 29er inside. When it got dirty, I would have to put an old blanket down to keep the interior clean which got to be a pain.
I saw that Kuat recently released 15mm and 20mm thru-axle fork versions of The Dirtbag which was previously only in 9mm: Products » The Dirtbag | Küat
This got me thinking - I know that they are normally used for mounting to truck beds, but why couldn't I simply mount The Dirtbag directly to my cross bars? After a quick search, I found this article that proved it was possible: DiY Bike Racks | Singletracks Mountain Bike Blog
So I picked up a 15mm Dirtbag for $19 and stainless steel hardware (to protect against rust) from my local hardware store for $6. I purchased two 3/8" bolts, five washers, two locking washers, and two locking nuts.
The 15mm Dirtbag needs a 3/8" hole, so I purchased a new drill bit set that was specifically for drilling metal. I needed a new drill bit set anyway. Here are my process photos.
My tools with the holes drilled into cross bar. My cross bars have a rubber top (for gripping cargo I assume) and underneath is the aluminum bar. Note the towels and wood block for protecting the top of the car. I don't need another sunroof by punching through the roof with the drill:
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My two holes drilled with the rubber pulled back:
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Because the cross bars have a slight arch, I had to use washers on one side to make the mount level. I used washers on the bottom and three washers on one side to level it out using a small level:
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A close-up shot of the mounting hardware before tightening.
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Front and rear photos of the mount.
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For the back wheel, I picked up a short cinch-type strap from Kuat to lock down the back wheel. I had to move my back cross bar further up the rails just a bit to get it in the right place:
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A couple of photos of the bike on the roof:
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VERDICT: The bike is surprisingly solid on the mount and after I tightened down the cross bars to the roof rail, I am confident that the cross bars would come off before the Dirtbag or bike. When I shake the bike, it shakes the whole car. I have driven it around rough roads and at highway speeds and have had no problems.
In fact, I liked the 15mm Dirtbag so well, I went and installed a 9mm Dirtbag the next day. Two bikes fit perfectly on top of the car and I might install a third Dirtbag facing backwards to fit a third bike on top.
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Not bad for $25 each and a couple hours of work!
++UPDATE++
I added a second 9mm Dirtbag to fit a third bike in the middle. Installation was quick and painless (since I had experience with the first two Dirtbags). There is the exact amount of room between the bike saddles and handle bars and all three sit nice and strong on the roof.
Here are a few photos of the three-bike setup with two 9mm and one 15mm Dirtbag mounts:
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Kuat makes the best bike racks on the market (in my humble and Springfield, Missouri opinion) and I have been wanting to purchase a Kuat NV rack since they first came out: Products » The NV | Küat Unfortunately, my car does not have a trailer hitch, so adding in the cost of the hitch, the bike rack was out of my price range.
I have a 2001 Volvo XC70 Wagon and the original owner had factory roof cross bars installed. Until last week, I was laying down the back seat and fitting my 29er inside. When it got dirty, I would have to put an old blanket down to keep the interior clean which got to be a pain.
I saw that Kuat recently released 15mm and 20mm thru-axle fork versions of The Dirtbag which was previously only in 9mm: Products » The Dirtbag | Küat
This got me thinking - I know that they are normally used for mounting to truck beds, but why couldn't I simply mount The Dirtbag directly to my cross bars? After a quick search, I found this article that proved it was possible: DiY Bike Racks | Singletracks Mountain Bike Blog
So I picked up a 15mm Dirtbag for $19 and stainless steel hardware (to protect against rust) from my local hardware store for $6. I purchased two 3/8" bolts, five washers, two locking washers, and two locking nuts.
The 15mm Dirtbag needs a 3/8" hole, so I purchased a new drill bit set that was specifically for drilling metal. I needed a new drill bit set anyway. Here are my process photos.
My tools with the holes drilled into cross bar. My cross bars have a rubber top (for gripping cargo I assume) and underneath is the aluminum bar. Note the towels and wood block for protecting the top of the car. I don't need another sunroof by punching through the roof with the drill:
My two holes drilled with the rubber pulled back:
Because the cross bars have a slight arch, I had to use washers on one side to make the mount level. I used washers on the bottom and three washers on one side to level it out using a small level:
A close-up shot of the mounting hardware before tightening.
Front and rear photos of the mount.
For the back wheel, I picked up a short cinch-type strap from Kuat to lock down the back wheel. I had to move my back cross bar further up the rails just a bit to get it in the right place:
A couple of photos of the bike on the roof:
VERDICT: The bike is surprisingly solid on the mount and after I tightened down the cross bars to the roof rail, I am confident that the cross bars would come off before the Dirtbag or bike. When I shake the bike, it shakes the whole car. I have driven it around rough roads and at highway speeds and have had no problems.
In fact, I liked the 15mm Dirtbag so well, I went and installed a 9mm Dirtbag the next day. Two bikes fit perfectly on top of the car and I might install a third Dirtbag facing backwards to fit a third bike on top.
Not bad for $25 each and a couple hours of work!
++UPDATE++
I added a second 9mm Dirtbag to fit a third bike in the middle. Installation was quick and painless (since I had experience with the first two Dirtbags). There is the exact amount of room between the bike saddles and handle bars and all three sit nice and strong on the roof.
Here are a few photos of the three-bike setup with two 9mm and one 15mm Dirtbag mounts:
