Drag Penalty for Bikes On Roof? - Escape Trailer Owners Community
Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×

Go Back   Escape Trailer Owners Community > Escape Tech > Problem Solving | Owners helping each other
Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 09-29-2014, 09:07 PM   #1
Senior Member
 
Join Date: Mar 2013
Location: Yellow Springs, Ohio
Trailer: 2013 Escape 19
Posts: 709
Drag Penalty for Bikes On Roof?

Does anyone have any reasonable comparisons for fuel mileage with and without bikes on top of the car (Highlander in our case) when towing an Escape? There is a definite drag penalty for bikes on the roof under normal highway driving, but I'm wondering if it's that much worse compared to the big hit already incurred from towing.

We have a great Saris rack that fits in the receiver on the Escape, but it's really heavy. That and the two bikes add more weight back there than I'd like. If it's not too big a mileage hit, I think I'd move the bikes to the roof of the car, but I hate to invest in more bike rack stuff just to try it.
Parker is offline   Reply With Quote
Old 09-29-2014, 09:22 PM   #2
Senior Member
 
bisonbill's Avatar
 
Join Date: Nov 2013
Location: Windham, CT, Connecticut
Trailer: 2014 Escape 21
Posts: 188
We often have kayaks on the roof of the Ridgeline. The mileage penalty is 1-2 mpg without the trailer. It tends to drop to 16-17. With the Escape hooked up and the kayaks we seem to drop about 1 mpg from the trailer with no kayaks. With the kayaks and trailer it's about 10 to 10.5.

I think we get drag from the kayaks or the Escape, but it doesn't double when we we add both.
__________________
Bill and Ann-Marie

Most injuries injuries in old men occur because they think they are young men!
bisonbill is offline   Reply With Quote
Old 09-29-2014, 09:28 PM   #3
Senior Member
 
Join Date: Mar 2013
Location: Yellow Springs, Ohio
Trailer: 2013 Escape 19
Posts: 709
Quote:
Originally Posted by bisonbill View Post
I think we get drag from the kayaks or the Escape, but it doesn't double when we we add both.
That's what I was hoping to hear. Towing, I'm generally driving a little slower, which also helps with the drag situation. I really appreciate an actual comparison with numbers. Thanks.
Parker is offline   Reply With Quote
Old 09-29-2014, 09:40 PM   #4
Site Team
 
rbryan4's Avatar
 
Join Date: Jun 2014
Location: Canyon Lake, Texas
Trailer: 2015 19 "Past Tents", 2021 F150 Lariat 2.7L EB
Posts: 10,222
Maybe you should compare it both ways? Yes there will be added weight on the rear, which means your tongue weight will decrease and maybe require the shifting forward of cargo, but there would be almost no wind resistance mounted on the rear. Maybe its a wash?
__________________
"You can't buy happiness, but you can buy an RV. And that is pretty close."
rbryan4 is offline   Reply With Quote
Old 09-29-2014, 09:47 PM   #5
Senior Member
 
Join Date: Mar 2013
Location: Yellow Springs, Ohio
Trailer: 2013 Escape 19
Posts: 709
That's what I'm trading off. The rear rack keeps them down out of the wind. They do get really crudded up from road grime, but that's not terrible. It just always feel wrong to load that heavy steel rack and then two bikes that far behind the axles, even if things balance out okay, statically at least. Dynamically, that's a lot of weight in the wrong place. But then we've towed them several thousand miles that way, so maybe I have a solution looking for a problem.
Parker is offline   Reply With Quote
Old 09-29-2014, 10:01 PM   #6
Site Team
 
rbryan4's Avatar
 
Join Date: Jun 2014
Location: Canyon Lake, Texas
Trailer: 2015 19 "Past Tents", 2021 F150 Lariat 2.7L EB
Posts: 10,222
Yeah, I dunno. As long as handling and stability aren't affected. Was just thinking about the gas mileage.
__________________
"You can't buy happiness, but you can buy an RV. And that is pretty close."
rbryan4 is offline   Reply With Quote
Old 09-29-2014, 11:05 PM   #7
Senior Member
 
Join Date: Jul 2009
Location: Silverdale, Washington
Trailer: No more Escape 21
Posts: 412
Perhaps this may be of help. On my former Escape 19, I carried two bikes that weight a total of 66.4 pounds and the Thule rack was 23.1 pounds, total of 89.5 pounds. The tongue weight was reduced by 40 pounds, from 360 to 420 lbs, when carrying the bikes.
__________________
2008 Toyota Highlander
RickM is offline   Reply With Quote
Old 09-29-2014, 11:15 PM   #8
Senior Member
 
Join Date: Dec 2012
Location: Edmonton, Alberta
Trailer: 1979 Boler B1700
Posts: 14,935
We have not carried bikes on the roof, but we have carried a large canoe and (not at the same time) used a Thule rooftop carrier box with and without our current trailer (which is roughly as tall and wide as an Escape 19'). Without the trailer the canoe and box both certainly add drag, but with the trailer the canoe or box makes little if any difference to fuel consumption. Bikes are terribly shaped compared to this box or even the canoe, but maybe in front of the trailer they won't matter much?
Brian B-P is offline   Reply With Quote
Old 09-29-2014, 11:24 PM   #9
Senior Member
 
Join Date: Dec 2012
Location: Edmonton, Alberta
Trailer: 1979 Boler B1700
Posts: 14,935
Although rearward weight shift (seen as reduced tongue weight) is one result of adding mass to the back of the trailer, it is not the only effect. Adding mass out at the ends is bad for stability, and just adding more mass to the front to restore the tongue weight does not counteract the adverse effect on stability.

Although it is not desirable to have bikes in the airstream - for drag, or for the bikes - the tug's rooftop seems to me like a better place for them than the back of the trailer.

We have not carried bikes with the trailer; we have with our motorhome, in a rack on the back, but in that case on the back is the only reasonable option - the roof is certainly out of the question.
Brian B-P is offline   Reply With Quote
Old 09-30-2014, 05:23 AM   #10
Senior Member
 
Chapitre's Avatar
 
Join Date: May 2012
Location: Halifax, Nova Scotia
Trailer: 2014 5TA/ *012 17B (previous)
Posts: 442
I've carried two bikes and a swagman rack on the back of our previous 17 and had the same result as above - tongue weight was 40lbs less. I added weight ( water jugs with sand, so I could adjust easily). I drove 12k miles or so overall with them on, and never noticed a problem with stability.
__________________
Min D
Chapi II
--------------------
'Have No Regrets'
Chapitre is offline   Reply With Quote
Old 09-30-2014, 09:51 AM   #11
Senior Member
 
dave macrae's Avatar
 
Join Date: Jun 2012
Location: St.Albert, Alberta
Trailer: 21 ft November 17th
Posts: 847
I have had bikes up on the roof with the spandex covers to keep the bugs off the forks and bars and its like a sail. Noticed a drop in fuel mileage and could alsp notice a difference in power when passing on the highway. I have two styles of racks, one that you remove the front wheel and mount the fork to the rack and these are not as bad but I tried some that mount the bike with both wheels on and that really puts the bike up there along way to catch alot of air. I have also used a yakima sky box on the truck @ times. without the trailer its about 1-2 mpg penalty with the trailer theres no difference.
__________________
MacRae, 21ft
2016 GMC Yukon SLT
St.Albert Alberta
dave macrae is offline   Reply With Quote
Old 09-30-2014, 10:08 AM   #12
Senior Member
 
Join Date: Mar 2013
Location: Yellow Springs, Ohio
Trailer: 2013 Escape 19
Posts: 709
I've also had experience with two bikes on top with the spandex covers. I once tried this on a Prius when my son and I left for the starting point of a week-long ride. The bikes knocked the mileage in half! Needless to say, I switched to a hitch mounted rack. I'm thinking of racks that lock the forks down without the front wheel, and probably turning the bikes backwards so the rear tire get the first shot at bugs and such. If this works, I'll make up something to hold the front wheels on the rear bumper of the Escape. I'm happy to hear there is very little additional drag penalty after taking the big hit with the Escape. That seems to be the consensus.
Parker is offline   Reply With Quote
Old 09-30-2014, 11:09 AM   #13
Senior Member
 
santacruzer's Avatar
 
Join Date: May 2012
Location: Santa Cruz, California
Trailer: 2014 Escape 19
Posts: 755
I used to leave the crossbars in place on the Yakima rack on my Tacoma. Then I read a Consumer Reports article that stated just leaving racks in place can cost 1-3 mpg on average. I tested that and found it to be very true in my case. The racks came off! Those were just the cross bas, I can't imagine what the loss would be for those folks who leave their snowboard and and bike racks in place year-round.
__________________
2019 Tundra CrewMax Limited TRD 4WD
2014 Escape 19
santacruzer is offline   Reply With Quote
Old 09-30-2014, 03:17 PM   #14
Senior Member
 
Join Date: Dec 2012
Location: Edmonton, Alberta
Trailer: 1979 Boler B1700
Posts: 14,935
Quote:
Originally Posted by Chapitre View Post
I drove 12k miles or so overall with them on, and never noticed a problem with stability.
Good - but just be aware that you have less margin of stability than without the bikes. When a tug/trailer rig is at a speed near the limit of the trailer's stability, it will feel fine, but sway could be started by an emergency avoidance maneuver or a gust of side wind. It's hard to know how much margin is available - I don't know how fast our van could tow our current trailer before it became unstable, and my concern it that I unknowingly come too close.

(Although I have had the trailer at a too-high-to-mention speed once, so I'm not so concerned )
Brian B-P is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Escape Trailer Industries or any of its affiliates. This is an independent, unofficial site.


All times are GMT -5. The time now is 12:47 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright 2023 Social Knowledge, LLC All Rights Reserved.