Need advice on a Bike Rack for 4 bikes of which 2 are E-bikes

[Andro]

This 70.. 80 and 100k kg limit doesn't make any sense. 

 

My car is limited to tow up to 2 tons. Which is a Ave for a 2.2 to 2.4 L Diesel bakkie/SUV. 

 

I tow my boat at total weight of 1.6 ton from Cape Town to Mosselbay every holiday at speed between 80 to 115. 

 

Doubt 100kg is all a towbar can handle with 4 bikes at 120kg that hangs over the ball at about 1 to 1.4 meters. 

 

Don't worry about a few bikes on your towbar. Rather confirm your actual bikerack can carry the total weight of the bikes. 

Edited August 21, 2025 by Andro
Spelling

[ChrisF]

2 hours ago, Andro said:

This 70.. 80 and 100k kg limit doesn't make any sense. 

 

My car is limited to tow up to 2 tons. Which is a Ave for a 2.2 to 2.4 L Diesel bakkie/SUV. 

 

I tow my boat at total weight of 1.6 ton from Cape Town to Mosselbay every holiday at speed between 80 to 115. 

 

Doubt 100kg is all a towbar can handle with 4 bikes at 120kg that hangs over the ball at about 1 to 1.4 meters. 

 

Don't worry about a few bikes on your towbar. Rather confirm your actual bikerack can carry the total weight of the bikes. 

 

"tow limit" is the "pulling force" ... mostly in a straight line with the fixing points of the towbar system to the chassis.

 

"Ball weight limit" refers to the "downward force" on the ball.  This has a significant torque effect on the fixing points to the frame, thus the limit.

 

On an old school 4x4 with a strong "ladder chassis" it is possible to fit a custom towbar to maximise the tow and ball-point-loads.  Even so, be carefull as very few bakkies comes with properly rated bolts ... so have the system checked before pushing the limits.

 

 

With the typical modern car that is made from tin-foil ..... be CAREFUL to exceed manufacturer's limits.  I have seen how the mounting points deform when the point loads are exceeded.

 

 

The "tow ball" is not the weak point, but rather the "towbar-frame" that is bolted to the vehicle and then the vehicle frame's limitations.

[Mook]

I've seen a few debates/discussions on this topic on the 4x4 Community Forum and, more recently on Cars.co.za(link attached).

SA laws appear very archaic and many opinions support the Aussie rule of thumb where 10-15% of total load weight should be taken as max downforce on tow hitch.

https://www.cars.co.za/motoring-news/guide-to-safe-towing/294448/

[ChrisF]

15 minutes ago, Mook said:

I've seen a few debates/discussions on this topic on the 4x4 Community Forum and, more recently on Cars.co.za(link attached).

SA laws appear very archaic and many opinions support the Aussie rule of thumb where 10-15% of total load weight should be taken as max downforce on tow hitch.

https://www.cars.co.za/motoring-news/guide-to-safe-towing/294448/

 

Jip, letter of the law vs good engineering ....

 

just a few of the considerations of a good engineering approach:

- at what point does the point load on the ball start impacting steering, hugely dependent on each vehicles geometry

- frame strength

- actual strength of the towbar system and mounting

 

A well designed system easily loads a motorcycle, a real bike not an e-bike, on the towball.

 

A poorly designed system can, and HAVE, snapped chassis.

 

 

A Friday topic on its own .....

[Mook]

36 minutes ago, ChrisF said:

 

Jip, letter of the law vs good engineering ....

 

just a few of the considerations of a good engineering approach:

- at what point does the point load on the ball start impacting steering, hugely dependent on each vehicles geometry

- frame strength

- actual strength of the towbar system and mounting

 

A well designed system easily loads a motorcycle, a real bike not an e-bike, on the towball.

 

A poorly designed system can, and HAVE, snapped chassis.

 

 

A Friday topic on its own .....

You are right Chris,

Add poor material quality of the towbar, incorrect tyre pressures, worn shocks and lacking driver skills .................................  "there goes my everything" 

[Hamstring]

https://kuat.com/?srsltid=AfmBOop4jMtMfq8gKrhr3e-15s6YvsNryF1UoCwtMOoLpumHQmT4ySJ7

😛

[Nico De Bruyn]

Hi Guys,

I appreciate all the comments on this post, it does seem like there are a lot of views. But through all the comments I believe that I will go with the Vertorack. I drive the new Haval H6 HEV fitted with a Bosal Towbar with a vertical tow limit of 100Kg.

I believe I would be fine with 2 e-bikes and 2 normal bikes.

[Jurie Schuurman]

You cannot only look at the weight of the bikes and rack on a towball mount. The centre of  gravity of your loaded bicycle rack will be a good 400 to 600 mm away from the centre of the vehicle's tow hitch. So say a rack (30kg)+ 2 e-bikes (60kg) + 2 mtb's (30kg) = 120kg and the C.O.G. is 600 mm away from the hitch.

This means you have a vertical load of 120kg and because the rack is stiffly mounted (no rotation on the tow hitch ball as with a trailer or caravan) a bending moment of 120x0.6 m= 72 Nm imposed on the to hitch. This calculation is for static loading and gets worse in dynamic conditions which can increase the load and bending moment figures by a factor of 2+.

I will be very apprehensive of imposing those loads on a tow hitch. More so on the lighter duty tow hitches fitted to chassis less SUV or passenger vehicles.

We do a lot of offroad camping every year and I don't hang bicycles of the back of the vehicle or caravan as they get choked up(powder coated) with dust. (Much worse than in cycling on dirt roads).

So I either put them on the roofrack (Thule bike racks) when using the Subaru, which is ok for our mtb's but the e-bikes we bought last year is too heavy. Alternatively I load them on a homemade rack that screws onto the load tray of my bakkie (4 bolts, it is a 2 minute job) where they sit securely and dust free and I can still utilize the load space of the bakkie. Currently the rack is two rails, but it can be modified to take 4.

 

[Nico De Bruyn]

12 minutes ago, Jurie Schuurman said:

You cannot only look at the weight of the bikes and rack on a towball mount. The centre of  gravity of your loaded bicycle rack will be a good 400 to 600 mm away from the centre of the vehicle's tow hitch. So say a rack (30kg)+ 2 e-bikes (60kg) + 2 mtb's (30kg) = 120kg and the C.O.G. is 600 mm away from the hitch.

This means you have a vertical load of 120kg and because the rack is stiffly mounted (no rotation on the tow hitch ball as with a trailer or caravan) a bending moment of 120x0.6 m= 72 Nm imposed on the to hitch. This calculation is for static loading and gets worse in dynamic conditions which can increase the load and bending moment figures by a factor of 2+.

I will be very apprehensive of imposing those loads on a tow hitch. More so on the lighter duty tow hitches fitted to chassis less SUV or passenger vehicles.

We do a lot of offroad camping every year and I don't hang bicycles of the back of the vehicle or caravan as they get choked up(powder coated) with dust. (Much worse than in cycling on dirt roads).

So I either put them on the roofrack (Thule bike racks) when using the Subaru, which is ok for our mtb's but the e-bikes we bought last year is too heavy. Alternatively I load them on a homemade rack that screws onto the load tray of my bakkie (4 bolts, it is a 2 minute job) where they sit securely and dust free and I can still utilize the load space of the bakkie. Currently the rack is two rails, but it can be modified to take 4.

 

This makes a lot of sense. Would you argue it is then better that I rather go for a roofrack on my trailer, like the Top Runner Pro from Holdfast? I was just not sure what the weight is that the trailer lid can take and if that will make the trailer very imbalanced.

[DJuice]

At what speed can you travel with these vertical racks?

My wife`s car is also an H6, same tow hitch. We use my very old Thule Euro Way from 2002, but also need a new rack to take 4 bikes.

 

 

[Andro]

 

As don't drive a tin car and don't have an issue with dust as long it's not paint or tar. I will use my Tule 4 bike rack. 

 

I know of quite a few short cyclists which find it very difficult loading bikes onto a cars roof. 

 

His also have an impact on fuel consumption. 

 

I also use a S Bone 3 bike rack and found that loading 2 to 3 high end Mtb s (total weight of around 27kg) add quite some strain on most hatch and boot models. 

 

I guess each to his own.

How many incidents do any people know where towbar has failed loading bicycles? Guess this will be interesting. 

 

Another factor would also been was that towbar ever"abused"? 

[Andro]

8 minutes ago, DJuice said:

At what speed can you travel with these vertical racks?

My wife`s car is also an H6, same tow hitch. We use my very old Thule Euro Way from 2002, but also need a new rack to take 4 bikes.

 

 

Guess 120km. It's behind your vehicle so basically in the slip. 

 

Manufacturer is in Paarl you can give him a call. 

[Jurie Schuurman]

25 minutes ago, Nico De Bruyn said:

This makes a lot of sense. Would you argue it is then better that I rather go for a roofrack on my trailer, like the Top Runner Pro from Holdfast? I was just not sure what the weight is that the trailer lid can take and if that will make the trailer very imbalanced.

A bike rack on the trailer lid will be a good idea. It will depend on how sturdy the lid is but generally I think you will be ok. With the lid being closed there should be no problems, opening and closing it whilst loaded with 4 bikes may overload the hinges, lid handle etc. But these can be beefed up as I did on my son's Alustar trailer last week by fitting heavy duty hinges and reinforcing the lid corners so it can carry a large roofrack, two fishing kayaks and other gear.

[Andro]

1 hour ago, Nico De Bruyn said:

Hi Guys,

I appreciate all the comments on this post, it does seem like there are a lot of views. But through all the comments I believe that I will go with the Vertorack. I drive the new Haval H6 HEV fitted with a Bosal Towbar with a vertical tow limit of 100Kg.

I believe I would be fine with 2 e-bikes and 2 normal bikes.

Can't go wrong with Bosal and if fitted buy authorized fitment Centre you A - OK

[RobynE 🚵‍♀️]

I suspect the weight distribution for the vertical rack makes the calculation a little different?

I know that I much prefer to use my hanging rack on corrugated roads. My platform rack just bobs too much for my liking (and I see the same thing with brand new platform racks on vehicles in front of me heading to events). Even on the highway, going over a bridging plate or resurfaced road at 110+ km/h makes me feel quite ill with the platform rack. And I have recovery setups on both vehicles, not standard balls. 

[OVERDRIVE]

A bit off topic but still need to sell my towbar from the polo if anyone looking: 

https://bikehub.co.za/classifieds/item/trailers/826931/brink-towbar-for-a05-pq25-poloa1-platfform

Back to the lecture at hand, never thought ebikes were so heavy.