Looking for a recommendation - Towball fitter - Bike Rack fitting

[davehartley20]

Dear Forum members

I am looking for someone to fit a tow ball to the stern of my narrowboat to take a bike rack (not to tow a caravan...probably).

Can anyone 

 

• Recommend someone (preferably in the southern half of the network)
• See any problems with fitting it to my boat ( is two bolts enough, length of threads, and so on)

 

I have attached pictures of my boat and a neighbour who has one ( and unfortunately no idea who did it; Came with the boat)

 

I did think about mobile towbar companies but thought they would have no experience with fitting to narrowboats?

 

Any help greatly received

 

Kind regards

Dave

[blackrose]

It looks like you just need a bracket made with a cut out for your rudder stock bearing. Once you have that then it would be easy enough to fit it yourself if you have a socket set or some spanners. 

 

Why don't you make a template from cardboard with the dimensions and hole sizes and get it made from 3mm stainless steel sheet? An engineering workshop should be able to do it for you. Because the cut out for the bearing would be quite deep on your boat you might want to go for 4mm sheet steel if the workshop can bend it, otherwise the two fixing points either side of the bearing might be too weak in 3mm? Others will know better than me. 

 

I don't really understand how that tow ball holds a bike rack but you've obviously seen it done. I wouldn't fancy bikes bouncing around on the back of the boat in a lock myself, isn't it easier and safer just to put them on the roof or even inside while you're cruising?

Edited September 25, 2023 by blackrose

[Jen-in-Wellies]

I concur. The hard bit of this is fabricating a suitable bracket to be bolted to the rudder bearing studs. A tow bar company are going to throw their hands up in horror at this, as they are used to dealing with standard fitting kits for standard vehicles. What you need is some one who can design and draw up such a bracket to interface between the studs and a standard tow ball and some one else who can cut, drill and possibly weld steel. This could be the same person. Alternatively, the person doing the drawing could be you, but be very careful in your measurements. A couple of hours work, if you do any painting.

I too would be concerned about catching bikes on lock gates and wouldn't want them there when cruising.

 

I'd worry a bit about the bending forces on the bracket held by just the two bolts on your bearing. I would want a third point of support, possibly a bumper to rest on the fuel tank top.

[Tony Brooks]

As the stern plates, including the top forms the diesel tank you have problems. As others have said all I can see is a bracket to fit onto the rudder bearing but, unlike the photo that has a fair amount of horizontal surface to bolt down onto yours just has two thinish up stands, so I think you may need more than 3mm of steel. Even then I fear it will vibrate with a bike on it. If it does, then it may eventually crack and fall off.

 

The only other way would be to get a substantial drilled and tapped block of steel welded onto the stern, but that would be a boatyard job.

 

I agree with Jen, I think the bike would be prone to damage while cruising.

[David Mack]

And how is the bike supported from the towball? I would have thought some sort of horizontal support would be needed, but what to? If the system is relying solely on friction between a clamp bracket and the surface of the ball and then bending on a thinnish metal bracket I wouldn't rate the chances of success as very high.

[Stroudwater1]

There’s some very good bike holders that appear self supporting you see on the roads these days, Thule make some. 
 

As the bike is around 6 foot long  it seems a reasonable thing to me rather than have it scratching the roof especially if it’s a hefty E-bike? 
 

 

[Tony Brooks]

1 minute ago, David Mack said:

And how is the bike supported from the towball? I would have thought some sort of horizontal support would be needed, but what to? If the system is relying solely on friction between a clamp bracket and the surface of the ball and then bending on a thinnish metal bracket I wouldn't rate the chances of success as very high.

 

I think the bike carrier normally hooks over the top of tailgate, maybe the OP has a pram hood to hook the top into , or maybe he intends to fix it to the stern rail, as it looks as if it might be a cruiser stern.

 

I suspect the green boat may have used the ball for mooring with a scaffold pole on rivers, with the other end of the pole also pivoted so the boat can rise and fall.

 

My son and DiL kept their bikes in the smallish rear cockpit, chained to the starboard rail when on their summer cruises. It seemed to work well.

[MtB]

8 minutes ago, David Mack said:

And how is the bike supported from the towball? I would have thought some sort of horizontal support would be needed, but what to? If the system is relying solely on friction between a clamp bracket and the surface of the ball and then bending on a thinnish metal bracket I wouldn't rate the chances of success as very high.

 

 

 

There are lots of proprietary bike racks for cars that fit onto just the towing ball, surprisingly. Like this one:

 

Actually hanging the bike on requires one to stand behind the csr though, so that won't be so easy on a boat.

 

 

 

 

 

Edited September 25, 2023 by MtB
Add a bit.

[magnetman]

I wouldn't hang a bike off the back of a boat but if you are going to do it then I'd suggest finding a welding shop and as suggested give them the cardboard template. Make the holes a bit bigger to allow for inaccuracy. 

 

Before bolting down I think you could wedge a piece of rubber pipe fender under the flat part, behind the bearing then as you bolt it down it would squash the rubber which would form a support so the part didn't bend. 

 

If you show the image of the image of the other one to the welder and give your own measurements it should be alright.  I still wouldn't hang a bike there although quite a few do. 

 

 

Edited September 25, 2023 by magnetman
typo and removed odd giraffe references

[Tacet]

A couple of short lengths of angle iron bolted through the bearing housing with a flat plate welded across the back.  This would be easier to fabricate than the shaped and bent piece of the neighbours.

 

But whatever the arrangement, I agree it need more than only being cantilevered off the narrow support provided by the bearing housing.  A couple of rubber door stops pressing on the top of the fuel tank would be better than nothing.

[David Mack]

38 minutes ago, MtB said:

 

 

 

There are lots of proprietary bike racks for cars that fit onto just the towing ball, surprisingly. Like this one:

 

Actually hanging the bike on requires one to stand behind the csr though, so that won't be so easy on a boat.

 

 

 

 

 

Hmm. Frankly I find the idea of hanging 4 bikes off the back of the car like this to be pretty dodgy.

 

The forces on the interface between the clamp and the ball will be significant, particularly if the car is bouncing over uneven roads, and in the video the chap didn't even seem to do the clamp up that tightly. 

Thule are a brand leader, so I guess it must work, but I do find it rather unlikely.

However I note that in the video the towball is supported from the car with a bracket which is much more substantial then the bit of bent metal plate in the OP's photo.

[MtB]

5 minutes ago, David Mack said:

Hmm. Frankly I find the idea of hanging 4 bikes off the back of the car like this to be pretty dodgy.

 

The forces on the interface between the clamp and the ball will be significant, particularly if the car is bouncing over uneven roads, and in the video the chap didn't even seem to do the clamp up that tightly. 

Thule are a brand leader, so I guess it must work, but I do find it rather unlikely.

However I note that in the video the towball is supported from the car with a bracket which is much more substantial then the bit of bent metal plate in the OP's photo.

 

 

Yep, agree with all of that. I wouldn't be surprised if there was a special tow ball they sell with a blind hole drilled in it for that bolt to engage in to stop the whole thing slowly hinging down to the ground as the car goes along with four bikes hanging on it.

 

Four bikes can easily weigh 100kg and cannot imaging that bolt being good enough no matter how much one tightens it.

[David Mack]

 

Here's an alternative suggestion. Grind a small flat on the top guard iron right on the centreline of the boat. Then drill and tap two holes right through the guard iron and the hull plating, and bolt the towball directly to the hull. No intermediate bracket required.

The holes will go into the fuel tank, but this is right at the top of the tank so will be above fuel level unless the tank has been brimmed, but you could always use a sealant on the bolt threads.

[jonathanA]

its a good few years since I used to carry Mountain bikes on the back of my Landrovers ! but I had a 'witter' fitting that bolted between the towball and the towball bracket. It was a sort of socket thing that you fitted a 'stand' to it when you wanted to carry bikes.  

 

this sort of thing https://www.witter-towbars.co.uk/bike-racks/flange-towbar-mounted-3-bike-carrier-spare-wheel-110mm

 

The point is that with something like that you don't actually need the 'towball'  and aren't trying to clamp something to a 50mm ball. It didn't need any 'top' support or strapping to the tailgate like the thule ones linked to above. 

 

A welder mate made up another bracket for me so I could have one on two cars.  I can't remember whether I ever carried 3 bikes on it but regularly carried two.  ( I think it was space rather than weight that limited for me)

 

As others have said you need some thing to take weight on to the top of the counter under the bracket fixed to your bearing.  

[Hudds Lad]

I've been using one like this on the car for years, easy-on with a spanner. Can stand my fat @ss on it and it will not budge. I'd not entertain having one on the boat though.

When not in use you'd be advised to remove it or you'll find the straps get nicked, DAMHIK. I always stuck it in the boot once the bikes were off.

 

[magnetman]

Quite large bolts. They look about M14. 

 

Thats a serious bit of tapping work and with there being two separate pieces of steel (the rubbing strake and the boat itself) I think there would be a high probability of having trouble getting the tap right through. 

 

Might work. I've only done up to M10 tapping so don't actually know but it looks like hard work and risk of breakage and tap getting stuck on the hole. 

 

 

Also a very difficult position to work. 

I think you'd need a mag drill but will they grip on curves? 

 

 

 

 

I have in the past used a lever to push a drill in at an odd angle so I suppose one could fix a length of wood to the hole in the rudder and use that as a possible mechanical advantage but then you drop the drill in the water ! 

[Jen-in-Wellies]

1 hour ago, MtB said:

Four bikes can easily weigh 100kg and cannot imaging that bolt being good enough no matter how much one tightens it.

More like 60kg, unless they are all electric assist, then yes, 100kg. 10 to 15kg is a good estimate for a non-electric bike, excluding super lightweight racing things. 13 to 25kg for an electric bike typically.

[mrsmelly]

Bin the bikes.

[Jen-in-Wellies]

30 minutes ago, mrsmelly said:

Bin the bikes.

Put a car (or two) on the back of the boat instead.

Alf van Beem, Public domain, via Wikimedia Commons

[Mike Tee]

If you eventually get/decide on a bracket, forget the tow ball and get a ‘2” square receiver’ - google will help but think 4x4 - and the accessory’s that are about that fit into the 2” receiver are, I think, far better than tow ball ones.

[David Mack]

5 hours ago, Jen-in-Wellies said:

Put a car (or two) on the back of the boat instead.

Oh. I thought you meant more like this.

[Hudds Lad]

4 minutes ago, David Mack said:

Oh. I thought you meant more like this.

Wasn't there one with some sort of Galaxy/Sharan type back end as well?

[blackrose]

10 hours ago, Tacet said:

A couple of short lengths of angle iron bolted through the bearing housing with a flat plate welded across the back.  This would be easier to fabricate than the shaped and bent piece of the neighbours.

 

Yes that would be easier to fabricate.

[davehartley20]

Thank you everyone for your helpful, and humorous suggestions. Quick responses, loads of different stuff to think about with options. I feel darn lucky to have access to you lot.

 

We are just about to set off from the River Wey as continuous cruisers, heading north so initially I will take one of the suggestions (store it in the cratch while cruising, and on the roof at the end of the day), but will want a longer-term solution to get it off the roof and out of the well deck. All your input I will be chewing over and chatting at boatyards as we travel. 

 

Please keep the thoughts and suggestions coming and again, thank you, very much appreciated

 

Kind regards

Dave

 

P.S. I already have the bike rack, similar to the one in the picture. I don't have to use it in a solution just my starting point

 

[magnetman]

3 hours ago, Hudds Lad said:

Wasn't there one with some sort of Galaxy/Sharan type back end as well?

Yes there was. There is a picture somewhere on here of it. 

Quick google image search of 'car narrow boat' found this one which looks a bit VW ish but could be a Ford. I always have trouble telling them apart.