cartopping a tupperware boat in the heat

I just got a 17-foot rotomolded boat, and will be driving across the country soon in the hot summer heat. Assuming I don’t want it to oil can (true), how should I carry it? What kind of a rack should I use? J’s? For such a large boat?

I don’t really think length matters as far as the oil canning is concerned. The tupperware boats seem to bulge around bulkheads and in front of the seat,or under the seat,regardless of length. I think having the boat upside down on the rack is the best way, at least it works great for me. using generic foamies and straps. this way straps hug the contour of the hull instead of making a pressure point.

The J hooks
the side of the boat is stronger than that top and bottom, so its best to have the weight on it.

Three years ago I had two 17 footers
on the roof on a trip from NC to Alaska and they were there every day for three months except when we were paddling them.

I had them on cradles, and when we wern’t using them and not traveling I would just loosen the straps.

I didn’t have any “oil canning”

I do agree with the fact that sideways on J cradles they will take less stress.



Not your momma’s plastic
Rotomold is some fairly incredible stuff, you don’t have to baby it. It’s used to make stuff exposed to constant weather & abuse, truck fenders & tool cases for example.

Save your worries for the cedar strip boat.

Rotomold IS your mommma’s plastic, which warps easy if squished down,especially in the sun.

Depending on the boat, J cradles may be better than upside down. My Elaho has a very strong flat-ish deck so it’s happy being upside down on the rack, lots of boats like Tempests have a more flexible more rounded deck so J cradles are better.

I see just as many rotomolded boats that are incredibly badly warped and dented as I see which are not warped. If you strap it down tightly, even with saddles, and let it sit in the sun, you risk getting enormous dents (“dents”, not oilcanning, which is when the hull bends and “pops” in and out with no permenant distortion). One woman I know keeps her rotomolded kayak on the car for more than half the time in the summer, and permenant dents at the saddle locations are six inches deep. Jack’s advice is good: Loosen the straps during those times when they don’t need to be tight, and I’d add, don’t make 'em tighter than you have to the rest of the time.

I would…

– Last Updated: Jul-06-06 3:33 PM EST –

Use a regular ol Yakima or Thule roof rack with some kayak saddles or one of their J-shaped kayak carriers. Next best choice is put it cockpit-down on a roof rack, with the rack bars just far enough apart to touch the back lip of the cockpit in the back and the front bulkhead in the front. Next best would be to use some of those temporary shaped foam saddles placed precisely where the bulkheads are.

You definitely don't want to put it hull-down on anything at all, especially in the summer, or you're asking for dents.

One option you might want to consider is just shipping the thing. If you don't have a rack already, it will be by far the cheapest option. Shipping would only cost you about $75 or so depending on where it's going. It may be especially economical considering the gas mileage increase you'd experience by not having a kayak on the roof of your vehicle.

j racks
I don’t know why folks bother with saddles.


– Last Updated: Jul-06-06 3:53 PM EST –

Easier to load

What do ya mean by that?
I use Yakima stuff, and have a few different set-ups, and I’ve decided a bunch of years ago that my Mako saddles have worked best for me. I have rollers, but at least for plastic boats, the saddles are my best set-up. I don’t have the J cradles, however…

Your vehicle gets blown around on the highway quite a bit more with the J-holders vs saddles.

when they first came out
I used saddles, and they had to be readjusted with any different kayak that went on, and removed for any other roof load. Then I used cut blocks of 3" minicell that fit my kayak hull exactly with a slot to fit onto the yakima bars. So for $50 of minicell I had something that could be put on/off quickly and it fit the hull perfectly. Then I got stackers and J saddles and now it doesn’t matter what kind of kayak it is,they all fit.

Thanks for the advise!
Shipping sounds like a good idea. Or I may just find a cheap pair of stackers and foam pad for the bars, and carry it on its side.

foamies and straps
I travelled 400 miles with my sirocco on foam blocks with straps and tie-downs on the bow and stern. There was absolutely no denting at all. I just snugged it with all straps and tie-downs and it rode the 8 hours just fine.

My rotomold is better than yours
My 16’ has been truck-topped & ready for most of the summer, if the temps drop below 85 I’ll stop & paddle on my way home from work… If above 90 it absolutely stays up there cause it’s too hot for me; but not too hot for the rotomold.

Patently absurd.

– Last Updated: Jul-08-06 2:40 PM EST –

"Shipping would only cost you about $75 or so depending on where it's going"

When u back 2 IL, Boheme?

Rack options…
The J-racks seem to be the most “boat friendly” way to transport, but has anyone had issues with the way they ride at highway speeds? Is the difference noticable compared to using saddles?

(I have a 14.5’ boat)

Not a problem for me

– Last Updated: Jul-11-06 2:46 PM EST –

62 pound 17 foot tempest 170 on a Subaru WRX (compact car). I hardly noticed a difference (well, aside from the decrease in fuel mileage). That may not be the case on a stock Subaru as I've modified mine a bit for autocrossing. Specifically I removed the stock springs and installed ProDrive springs which are stiffer and have a linear response curve vs. your standard stock spring which is soft and has a non-linear response (the linear springs improve turn in response). I also put thicker anti-roll bars on the front and rear (22mm vs. 20mm) which all dramatically improves the handling of the vehicle. I noticed that after doing this the car was much more stable in cross winds (going over the GGB, Dumbarton, and San Mateo bridges when I used to live in the SF/Bay Area) so I'm sure that added stability helps when cartopping the yak but as to how much, I have no frame of reference as I've not c-topped it on any other vehicle. As an added benefit having the car lower to the ground makes it easier for me to lift that thing on top of the car. LOL It's only about an inch lower but I'll take what I can get!

Now that I'm back in New England (where you drive into one side of a pot hole and out the other) I was considering putting the stock suspension back in but now that I have my new kayak.... I'm not so sure. LOL

Cheers, Joe


Nice car, but I wasn’t sure if you are you using the the J-rack, (Hullraiser)? Reading you post, I couldn’t tell.