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Old 05-22-2014, 02:31 AM   #1 (permalink)
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Interesting prelim results: Canoe on roof rack

Hey guys, I am restoring an old 18' kevlar canoe but first I need to get from my parents place to where I work up north.

I currently have it on a cheep Canadian Tire roof rack on my Nissan Versa. I was a little bit hesitant to put such a big canoe on such a small car but a roof rack is easier to find on short notice than a proper hitch to tow it on a trailer. I had to make a trip into the city to buy a rack, drive back with the rack installed, then haul the canoe north. I have a training course tomorrow so am not going all the way up to the base until tomorrow.

I figured I would record my fuel efficiency today in the various parts of my journey. It was a nice warm day today with low humidity and light breeze (5-10 km/h) from the west. I just recorded the average economy of various parts of the trip omitting the city stuff.

To town, naked roof, into wind, 110 km/h for 95 km - 7.0 L/100km
Trom town, with roof rack, with wind, 110 km/h for 95 km - 7.3 L/100km
North to PA, with canoe, cross wind, 110 km/h for 140 km - 7.7 L/100km


The additional .3 L/100km with the rack on was not very surprising to me it creates a fair amount of wind noise, I am not going to be driving around much with a naked rack.

Only adding another .4 L/100km for the canoe on the other hand really surprised me. Considering how much frontal area I added and the air that must be getting trapped at the top of my windshield I was expecting a substantial hit. I was also expecting minor issues driving like that with a cross wind but it seemed to actually track *better* with the canoe on top, almost like it was acting like a keel on a boat. I was expecting 9-10 L/100km and having to keep the speeds down to keep it between the lines.

It might be a different story with stronger gustier winds but the versa was a joy to drive with a canoe on top. The gearing finally felt right, the engine was definitely working harder but still never felt like it was even close to needing a downshift on the pavement. It kept it's line better than ever on the highway with a stronger than normal tendency for the steering to return to centre. It completely defied my expectations of the car being more affected by wind, meeting semis, etc, and the increased steering effort at speed was not a unwelcome change. It almost makes me consider making a boat tail, but I need to fix the boat before I start thinking about tails.


*phone is not cooperating, I will try to get some pics up tomorrow.*

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Old 05-22-2014, 07:37 AM   #2 (permalink)
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How did you put it on the rack ?
Right-side up or inverted ?
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Old 05-22-2014, 01:12 PM   #3 (permalink)
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I have carried canoes with roof racks on several different cars and trucks. My experiences are similar to yours - minimal effect on handling and roughly 10% hit on gas mileage. I do try to put the canoe as far to the rear as practical in order to minimize the "scoop" area in front of the windshield.

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