1 Up With 5 Trays?- Mtbr.com
Results 1 to 20 of 20
  1. #1
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061

    1 Up With 5 Trays?

    Has anybody ever tried it?

    I haven't done the math, but based on the rated capacity of 50 pounds per slot, it seems like 5, 25 to 30 pound bikes would present a net lower torque.

  2. #2
    Yeah!
    Reputation: Flamingtaco's Avatar
    Join Date
    Mar 2012
    Posts
    1,453
    I calculated the torque angles of the four position racks a few years back. Four XC bikes can max out a Class III receiver. For DH bikes, it's best to go Class IV or V. If you're going to void your warranty, go with the super duty rack. No guarantee you won't damage the rack or your receiver.

    That's a lot of bike dangling well past the rear bumper. Can't say I'd enjoy having bikes that far back. I'd rather have a trailer back there.
    I will suffer no butt-hurt fools!

  3. #3
    mtbr member
    Reputation:
    Join Date
    Feb 2005
    Posts
    418
    Quote Originally Posted by Metamorphic View Post
    Has anybody ever tried it?

    I haven't done the math, but based on the rated capacity of 50 pounds per slot, it seems like 5, 25 to 30 pound bikes would present a net lower torque.
    Have you considered the length of the lever arm as well as the weight?

  4. #4
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    I considered it, but like it said, I haven't taken the measurements and done the math.

    But it seems like the torque from

    --50--50--50--50

    would be more than something like

    --35--28--25--25--23

    Now its interesting that FlamingTaco says that 4 xc bikes would max out the class 3 hitch. I didn't consider that the hitch would be the limiting factor. Seems strange that 1up would build a rack stronger than the hitch it mounts to.

  5. #5
    mtbr member
    Reputation:
    Join Date
    Jan 2009
    Posts
    1,282
    Quote Originally Posted by Metamorphic View Post
    I haven't done the math,
    Obviously voiding the warranty, but would say the risk is low if you put the lightest bikes outboard and add a 3rd bolt to the most inboard add-on... there's already a hole there, just get a stainless bolt/nut/washers from the hardware store.

    Pics required if you do it!
    Last edited by J_Westy; 03-11-2016 at 08:49 AM.
    --------------

    [WTB] 1987 Cannondale SM800, 20", Pink with airbrushed graphics.

  6. #6
    mtbr member
    Reputation:
    Join Date
    Aug 2006
    Posts
    531
    Depends on where you are, and your vehicle, but the other issue is MV laws regarding how far things can protrude from the of the vehicle.

    IIRC, in BC it is 12'. It also may be a percentage of the wheelbase. On my truck, 5 would be pushing the limit.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Oct 2008
    Posts
    2,208
    That's going to put a LOT of torque on those two bolts for the first add on.

    j.

  8. #8
    Yeah!
    Reputation: Flamingtaco's Avatar
    Join Date
    Mar 2012
    Posts
    1,453
    Quote Originally Posted by Metamorphic View Post
    Seems strange that 1up would build a rack stronger than the hitch it mounts to.
    1) It's not their responsibility to select the correct receiver for their product, and the NHTSA does not actively drive oversight for random failures that are user incurred. A sudden spike in OEM tire blow outs across a few vehicle models, they perk up. Random receiver failures due to user error are not a design concern.

    2) 1UP doesn't have any racks that go beyond the weight range of the receivers they fit. Class III and IV are both 2" receivers. III are designed for over 300Lbs TW. Class IV permits up to 1000Lbs tongue weight. My class IV is rated for 600Lbs TW. The rating is whatever the mfg makes it, within the range of the class they want to sell it as, and hell, sometimes they don't stay within the lines.

    You can get a Curt class IV rated 1200Lb TW, 12,000 Lb for $360. My Reese 600/6000 sold for $220. Weight capacity is a value adding feature. That 1200/12000 receiver probably costs $30 more in material and labor than the 600/6000 model.
    I will suffer no butt-hurt fools!

  9. #9
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    Quote Originally Posted by jaks View Post
    Have you considered the length of the lever arm as well as the weight?
    Ok. I did the math
    1 Up With 5 Trays?-fullsizerender.jpg

    Looks like 5 light xc bikes have a static torque of about 17% less than the 4, 50 pound DH bikes that are the marketed capacity.

    Im thinking with bolts in the first two extra holes this is do-able.

    This would be a lot easier if everybody could figure out how to their own lazy selfs to the trail head.

  10. #10
    mtbr member
    Reputation:
    Join Date
    Apr 2017
    Posts
    109
    Quote Originally Posted by Metamorphic View Post
    Ok. I did the math
    Click image for larger version. 

Name:	FullSizeRender.jpg 
Views:	58 
Size:	77.6 KB 
ID:	1133816

    Looks like 5 light xc bikes have a static torque of about 17% less than the 4, 50 pound DH bikes that are the marketed capacity.

    Im thinking with bolts in the first two extra holes this is do-able.

    This would be a lot easier if everybody could figure out how to their own lazy selfs to the trail head.
    You need to add the weight of rack add-ons to the equation.

  11. #11
    Yeah!
    Reputation: Flamingtaco's Avatar
    Join Date
    Mar 2012
    Posts
    1,453
    LOL... a year and a month later. That's a timeline I can work with!
    I will suffer no butt-hurt fools!

  12. #12
    mtbr member
    Reputation:
    Join Date
    Sep 2010
    Posts
    125
    A lot depends on the vehicle as mentioned. I have a friend that has occasionally gone with five race xc bikes in a Surburban. I believe he added an additional bolt with the first add on. There is no way I would ever do that with my Honda Odyssey. Four race xc bikes is the max and I am using airbags to pick up the back end.

    Not that five is recommended but i think it would be a disaster with most vehicles. If I needed to go with five, I would carry four on the hitch rack and one on the roof.

  13. #13
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    Quote Originally Posted by Flamingtaco View Post
    LOL... a year and a month later. That's a timeline I can work with!
    Its a problem that crops up every so often in my life.

  14. #14
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    Quote Originally Posted by kosulin View Post
    You need to add the weight of rack add-ons to the equation.
    I'm looking to see if the 5th bike load is above the baseline of the marketing which indicates 4, 50 pound bikes, so I only need to consider the weight and moment of the 5th tray, which I did there in the last.

  15. #15
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    Quote Originally Posted by jhat View Post
    A lot depends on the vehicle as mentioned. I have a friend that has occasionally gone with five race xc bikes in a Surburban. I believe he added an additional bolt with the first add on. There is no way I would ever do that with my Honda Odyssey. Four race xc bikes is the max and I am using airbags to pick up the back end.

    Not that five is recommended but i think it would be a disaster with most vehicles. If I needed to go with five, I would carry four on the hitch rack and one on the roof.
    2017 Tundra - From what I read its a Class 4 hitch.

  16. #16
    since 4/10/2009
    Reputation: Harold's Avatar
    Join Date
    Dec 2003
    Posts
    26,583
    also worth noting here is going to be the effect of any bouncing while driving. probably not normally much of a consideration for normal cars/trucks (as opposed to RV's) but with the addition of the extra length, it's probably starting to become one.

    Count me as another person who feels like a small trailer is a better choice. And since you've got a truck, why not put one of the bikes in the bed?

  17. #17
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    Yeah, I realize that I'm not looking at the dynamic aspect of the situation. That 5th tray is going to have a higher bob velocity than the 4th tray because its a radial movement, and E=1/2MV^2. Gotta be careful with those squared terms.

    The truck bed pad is an obvious solution, but the bed will be full of ez-ups, trainers, water, food, stove, etc etc.

  18. #18
    Yeah!
    Reputation: Flamingtaco's Avatar
    Join Date
    Mar 2012
    Posts
    1,453
    Do you have a topper? If not, it would be easy to run some cross bars and put a single bike mount on either side of the bed (for easy access).
    I will suffer no butt-hurt fools!

  19. #19
    mtbr member
    Reputation:
    Join Date
    Jan 2009
    Posts
    1,282
    Quote Originally Posted by J_Westy View Post
    Obviously voiding the warranty, but would say the risk is low if you put the lightest bikes outboard and add a 3rd bolt to the most inboard add-on... there's already a hole there, just get a stainless bolt/nut/washers from the hardware store.

    Pics required if you do it!
    @OP: Did you ever try it? Pics needed!
    --------------

    [WTB] 1987 Cannondale SM800, 20", Pink with airbrushed graphics.

  20. #20
    Moderator Moderator
    Reputation:
    Join Date
    Apr 2011
    Posts
    2,061
    One guy begged off for the trip so we ended up with 4. Kinda relieved, kinda disappointed.

Similar Threads

  1. Locking bike trays question.
    By wellcraft in forum General Discussion
    Replies: 1
    Last Post: 11-28-2014, 10:46 AM
  2. Yakima Trays
    By paintlick in forum Cars and Bike Racks
    Replies: 2
    Last Post: 09-22-2014, 06:17 PM
  3. Roof trays --> hitch rack
    By the-one1 in forum Cars and Bike Racks
    Replies: 16
    Last Post: 07-08-2014, 12:55 PM
  4. Yakima raptor bike trays
    By blue_biker in forum Cars and Bike Racks
    Replies: 0
    Last Post: 09-06-2013, 01:04 PM
  5. Hitch Rack That Accepts Trays?
    By kill phil in forum Cars and Bike Racks
    Replies: 4
    Last Post: 04-25-2011, 03:45 PM

Members who have read this thread: 2

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.