Roof bars and roof box confusion

kfw_2

Hello all,


I have a new set of roof "aero" bars (brand - Menabo) the roof box I have (standard 400litre Karrite) U bolt fittings are narrow and are only suitable for standard square bars.


What are my options?? buy wider U bolts and drill extra holes into the base of the box? Some people say don't use U bolts with aero bars but I can't find much via google to confirm. Or buy a set of T track mounting points - which I understand are upside bolts which slide into the top of the narrow track.


Does anyone have any experience of the T track method, my immediate concern is that there will only be 4 bolts locking the roof box to the bars, whereas the U bolts will have 8 bolts.


Any experiences or recommendations would be greatly appreciated!!.:beer:

Iceweasel

Definitely convert to the T-track bolts connections.

Yes there are only 4 bolts as opposed to the 8 when you use U-Bolts but it's perfectly strong enough.

You may have to drill new holes in the box to get the whole thing properly re-aligned.

I have a Carrite 460litre Box which I used on the standard square bars on my Freelander TD4.

My BMW has Aero bars and the T-Bolts.

I fitted the bolts with the original Carrite metal plates sandwiching the plastic of the box to spread the load.

Solid as a rock at over 120mph.

forgotmyname

Do the box manufacturers still put 60mph max on them for health and safety reasons to protect nuns and kittens

Iceweasel

forgotmyname wrote: »

Do the box manufacturers still put 60mph max on them for health and safety reasons to protect nuns and kittens

Not too many nuns or kittens on the autobahnen.

Moto2

The people at roofbox.co.uk are very knowledgeable and extremely helpful.
They'll be able to sort you out with whatever you need

http://www.roofbox.co.uk/

IamNotAllowedToUseMyName

Moto2 wrote: »

The people at roofbox.co.uk are very knowledgeable and extremely helpful.
They'll be able to sort you out with whatever you need

http://www.roofbox.co.uk/

Second the roof box recommendation.

U bars are simply not designed to fit with aerobars, they would damage them. The T groove is strong and the clamping system is strong - your box will not be going anywhere.

I've got a large roof box and also bike racks. The box is easy to drop on by myself and you don't mark the bars sliding things around.

In terms of speed and load, all the different components have limits - I am fairly sure my roof box and bar combination had a recommended limit of 80mph, I've briefly taken it above that on the autobahn without any concerns, and of course try and pack the light, bulky things up there leaving the heavy stuff for the front of the load area.

forgotmyname

Iceweasel wrote: »

Not too many nuns or kittens on the autobahnen.

Always a first time though and manufacturers must be prepared for that. Imagine approaching a nun with a basket of kittens and your doing 61mph.

Exceeding the roofbox speed limit could cause your car to implode and them explode injuring said nun and maiming the kittens or at least causing them to lose one of their nine lives

Iceweasel

forgotmyname wrote: »

Always a first time though and manufacturers must be prepared for that. Imagine approaching a nun with a basket of kittens and your doing 61mph.

Exceeding the roofbox speed limit could cause your car to implode and them explode injuring said nun and maiming the kittens or at least causing them to lose one of their nine lives

The nuns can look out for themselves, but on account of the kittens I always keep a sharp lookout.

To be serious for a nano-second I was not suggesting that a roof-box should be subjected to mile after mile of 120mph.

I did briefly touch that speed at one point though and the box was completely stable and vibration free. I mentioned it by way of re-assurance to the OP that having 4 track bolts as opposed to U-Bolts with 8 nuts to tighten up was in no way a retrograde or less secure fitting.

For legal speeds in the UK there is absolutely no problem is securing the box with 4 of the correct size of track-bolts - but they MUST be the correct bolts - any old bolt will just lead to tears.

I think that not exceeding the max roof load weight (usually 75Kg) is more important than not exceeding any set speed limit.

alderpoint

IanMSpencer wrote: »

U bars are simply not designed to fit with aerobars, they would damage them.

The Whispbar comes with custom-profiled U-bolts for a roofbox and I've used these for the whole of winter for the past 5 years with no sign of any damage.

vikingaero

I have a Thule roofbox with U bolts. On one car I have square roof bars. On another car I can still use the U bolts with the aero bars - it depends on the size of the aero bars. I dislike using the T-track because of wind noise. You have to cut the rubber strips to infill and it's a pain when you swap to a bike rack. If you accidentally leave a gap in the rubber strip it still whistles.

As for speeds. Many German motorist travel far in excess of 100mph without problems.

alderpoint

vikingaero wrote: »

I dislike using the T-track because of wind noise. You have to cut the rubber strips to infill and it's a pain when you swap to a bike rack. If you accidentally leave a gap in the rubber strip it still whistles.

Don't have that problem on my Whispbars, the rubber strips have enough give in them that T-connectors can run between the strips and the actual bars, meaning that cutting the rubber strips is not necessary.