Maximum weight on tow bar

[loz65]

The manual for my C7 ultra avant states a maximum vertical weight on the tow-bar of 85Kg.

I will be using the tow-bar to attach a bike carrier. This may sound a stupid question, but does this mean that this will be fine provided that the combined weight of the carrier and bikes doesn't exceed 85Kg? Or will the combined weight have to be less than this to take into account the 'lever' effect of the bike rack hanging over the back of the car? Sorry, but can't get my head around this!

[zollaf]

the 85g is the nose weight of the trailer you are towing. too much or too little weight and you find yourself snaking down the road out of control. a tow bar is not designed to carry bikes , they are to tow with, but it will handle any bike rack and any amount of bikes you want to hang off it. realsitically it is designed to pull and stop a trailer of probably 2 tons, so don't worry.

[wildbore]

Errm, actually, the offset from the bar does limit the amount of weight you can carry. This is clearly stated in the Owner's manual. The 85Kg is a permitted nose weight but can act at an offset of 300mm from the tow bar ball. At 600mm you halve that limit. I think my loading sticker says 85Kg, but the Owner's book states the limit to be 75Kg, halved(ish) to 35Kg at 600mm.

What the bar can physically support and what it is certified to support are separate things. In an insurance claim, the insurer might look at a bicycle carrier mounted on the towbar that contravened the load limit and refuse a claim. If it fell off and caused an accident then the Police might start looking at the loading limits, too, I imagine.

[niall campbell]

As long as its not Apollo specials out of Halfords, the bikes shouldn't be too heavy

[loz65]

Errm, actually, the offset from the bar does limit the amount of weight you can carry. This is clearly stated in the Owner's manual. The 85Kg is a permitted nose weight but can act at an offset of 300mm from the tow bar ball. At 600mm you halve that limit. I think my loading sticker says 85Kg, but the Owner's book states the limit to be 75Kg, halved(ish) to 35Kg at 600mm.

What the bar can physically support and what it is certified to support are separate things. In an insurance claim, the insurer might look at a bicycle carrier mounted on the towbar that contravened the load limit and refuse a claim. If it fell off and caused an accident then the Police might start looking at the loading limits, too, I imagine.

Thanks wildbore. Could you just expand upon what you mean by 'offset'? The total length of the bike carrier from tow-ball to the end of the carrier is around 750mm, so what would this mean in terms of calculations? Would you halve the total length (on the basis that the load is spread roughly across this length) and therefore treat this as an offset of 375mm? If so, what would this mean for the total weight limit?

Sorry if I'm being thick.....

[wildbore]

The offset is the distance - horizontally - from the tow bar ball to the centre of gravity of the bike rack plus bikes. If your bike rack plus bikes is a total of 750mm from the back of the tow bar, then - assuming equal loading front to back, it is reasonable to estimate that the centre of gravity of the rack+bikes is situated at 375mm from the tow bar. Ideally, your rack+bikes should weigh under 85kg as you are beyond the 300mm limit for the 85Kg load allowance. As Niall Campbell indicated, unless your bikes are made of pig iron then you should be fine. And, as zollaf indicated, in reality the tow bar will not be unduly stressed if you marginally exceed its stated load capacity.

If the limit is 85Kg at 300mm and under half that (let's say 40Kg) at 600mm then your limit at 375mm is approximately 85 - [(85-40) x 75/300] = 73.75Kg.

Hope that helps!

[loz65]

The offset is the distance - horizontally - from the tow bar ball to the centre of gravity of the bike rack plus bikes. If your bike rack plus bikes is a total of 750mm from the back of the tow bar, then - assuming equal loading front to back, it is reasonable to estimate that the centre of gravity of the rack+bikes is situated at 375mm from the tow bar. Ideally, your rack+bikes should weigh under 85kg as you are beyond the 300mm limit for the 85Kg load allowance. As Niall Campbell indicated, unless your bikes are made of pig iron then you should be fine. And, as zollaf indicated, in reality the tow bar will not be unduly stressed if you marginally exceed its stated load capacity.

If the limit is 85Kg at 300mm and under half that (let's say 40Kg) at 600mm then your limit at 375mm is approximately 85 - [(85-40) x 75/300] = 73.75Kg.

Hope that helps!

thanks - that helps a lot and clears everything up!

[Splash]

Until I noticed a forum post from someone talking about caravans, I'd always thought this was the weight limit of a person standing on it to wash the car or fit a roof box etc.

There again, I also bought my wife an Apollo bike as a present after giving birth without considering the fundamental problem. It was a good deal...

[MarkTM]

I also bought my wife an Apollo bike as a present after giving birth without considering the fundamental problem.

Last of the big spenders...that poor woman!

[Splash]

Hey, that's how I roll...

In my defense, it was aluminium and allegedly made by Peugeot. Still on the same tyres from 12 years ago! Wonder why?

And besides, she just got a pressure cooker for Christmas. What more could a woman want?