Bike roof rack

[peterd51]

Hi Guys,

well it's been a while since I could do anything much in the workshop but I've finally finished the bicycle roof-rack that I started before Christmas!

It's mostly made out of old market stall, 1" box section, with a few odd scraps of flat thrown in. It started with a rectangle about 50" x 14"...



then I cut four lenths of box around 10" long and welded them to the outside edges of the long sides, one near each end. I found some bits of 3mm plate around 9" x 4" and used the plasma cutter to slice them in half long-wise and welded a couple of pieces to each side of these sections to hold the bike wheels.



The rack would be clamped to the roof-rack with four lugs and long bolts through from top to bottom. The lugs started out as 5mm x 25mm flat about 6" long. I cut a couple of grooves about half way through with the bandsaw, one cut on each side about 1/3 of the way in from the ends. Then I folded them in the vice into 'Z' shaped and welded up the splits.



Before attaching them I drilled holes and welded nuts on the ends of the brackets so I could hold them in place with a bolt and a clamp as I welded (I lost the original photo somehwere!)



continued in message 2...

 

[peterd51]

continued from message 1...

Now I needed to make an upright that the bikes would clamp to with elasticated stretchies. These stretchies would be used to hold the bikes up while I got some rope tied to the roof-rack and strapped them down properly.

The uprights turned out to be around 32" high with 6" strengtheners at 45 degrees near the bottom ends but before I welded these on I had the idea of bolting them in place so I could easily fold it up for storing.

The main problem I could see was the possibility of crushing the box when I tightened these bolts so I decided to add tubular spacers inside the box. It was easy on the uprights as the bolt holes were near the ends, but the ones in the main bed needed a 1/2" hole drilling and then spot welding the tube in place. I finished these off by tack welding a washer over the top of the hole to spread the load and to make it easier for the long upright to pivot without taking the paint off.





Now it was time to paint it and I decided to make it blue...mainly because I've got a gallon tin of blue paint to use up!

I tried it on the car last weekend and it pops onto the roof-rack nicely. You may note here that the roof-rack is also home made with brackets welded onto the car roof.

The tubes are 4mm wall steam-pipe that I clamp on/off as needed and it's pretty solid when it's on there. I've have 200KG+ of steel on there in 20' lengths and drove it home!



And finally, with a bike on it.



I was planning to make a second rack so we could put my sons bike with mine one side and the two oldest grandsons bikes the other side but I have to say that I hadn't considered the weight of the bigger bikes. It's easy to lift them to chest height but above head height is a struggle.

I'm now thinking of keeping this rack for the grandkids bikes and making the next one where I can fix it to the back of the car. I've not got a design yet but I guess it'll have a rail across the bottom that bolts onto the tow-bracket and the top will either clamp on the roof-rack or slip over the top of the tail-gate. I've taken some measurements today and checked those for sale on Ebay to get an idea or two.

Regards
Peter

 

[SC_BK]

We had one years ago mounted on the towbar, all you'd need to make it is some tube and a bender, and some other scraps

You just have 2 prongs sticking out the back that the bike frames hang on

 

[peterd51]

Hi,

yes, I've seen the ones that slip over the tow-ball but I don't fancy one like that.

I'd originally thought that the rack might clamp to the roof-rack and to the top two holes of the stabiliser plate on the tow-hitch but that's probably a bit too much.

So I fancy one that will hook over the top of the tailgate with suitable padding underneath and then either two ratchet straps or more likely two lengths of rope and tie the bottom end to the tow-hitch with a dolly hitch. Quick and easy to get on and off, and if the ratchets or ropes fail than the rack can't fall off as gravity will hold it in place...it'd just rattle around a bit until I stopped the car.

I knocked this up in MS word this morning...



Bear in mind this'll be 1" box so the 'hooks' won't stick out that far at the top and bottom ones would form a closed loop around the box.

The two lateral bars will be fastened in place with winged bolts so I can quickly dismantle it for storage.

Oops! just noticed I missed off the two strentheners for the sticky-out rails that the bikes will hang on...probably 1" box at a suitable angle or maybe extend the lower vertical rail straight up.

The only thing I need to find now is some strong rubber to make some quick grips, like car bonnet clamps but cheaper so I can just drop the bikes in the top pockets and clamp them in place. There's a place in Scunny that sells all sorts of belts, gears, etc, so I'll stick my nose in there next Saturday.

I guess then a ratchet strap from side to side across the tailgate and over the bikes would keep everything in place.

Regards
Peter

 

[SC_BK]

IMO that's a bit over-engineered

This is basically the one we used:

You have a mount thats bolted on behind the towball, then the rack tube is a larger diameter so slips on over the mount then an R clip keeps it secure. Only takes a few secs to take on/off
The 2 prongs sticking out are covered in padding (foam pipe lagging would do) to avoid scratches. All you need is a pair of bungees going round the bike(s) and the rack to hold them in place.
I was looking at the modern ones on ebay etc and they all look a bit flimsy, ours was just a big lump of metal




here's the mount fitted in place:

Don't forget you'll prolly also need a lighting board

 

[peterd51]

Hi,

thanks but if the bungee or strap came adrift you could loose everything off the back at 60+mph on the motorway...

with mine it'd stay on the car no matter what happened.

I agree with your observation that the Ebay ones looking a bit flimsy and some of them look a bit pricey to me.

I have a trailer board, already spotted that one... :-)

Regards
Peter

 

[novaweld]

SC's version with the bikes held on with small ratchet straps or D locks is what I'd go for.

 

[JimM]

Another advantage of the SC design is that if you need to open the boot it's going to be a lot less hassle to remove the rac.

I've got a Halfords rack similar to Peter's design and it's a real pain scrabbling under the car trying to find something to tie it down to.

 

[^neo^]

These are pretty good http://www.maxxraxx.co.uk/home.html (company opposite me makes them!)

 

[novaweld]

These are pretty good http://www.maxxraxx.co.uk/home.html (company opposite me makes them!)

The way the "foot" of that assembly bolts onto the ball is shocking, might be ok for a removable swan-neck style of towbar, but I'd much rather have it as a plate that's sandwiched between the towbar and towball by those two big bolts.

The upper bar doesn't look very secure at all.

 

[^neo^]

They're rock solid when they're fitted.

 

[peterd51]

Hi,

well, I have to disagree about being hassle to open the hatch.

There'd only be a couple of ropes to unfasten and with dollies it's a piece of cake to fasten/unfasten...why do you thing lorry drivers use them?

As for finding something to fasten to, how about the tow-hitch just underneath?

Actually thinking about it on the drive home this evening, with the weight keeping everything 'hooked' on the top of the tailgate it may be possible to get away with just a 1" ratchet strap from side to side, across the tailgate and over the bikes.

Then there'd be nothing to unfasten to open the boot, it'll all swing up on the tailgate hinges.

Although that could be a bit flimsy for me, I like things to stay where I put them. :-)

Regards
Peter

 

[JimM]

Fair enough Peter, I haven't got a tow hitch on my car and the bumper is plastic so I have to find a metal strut literally underneath the car.

One other point is that on my rack the tailgate top clamps are on straps so you can slide them between the tailgate and the aperture from the side. Not sure how you'd get yours mounted. With the tailgate up you couldn't do it from the rear of the car and not sure if the hinges would impede you from sliding it all the way across from the side ??

Whichever one you go for the biggest problem I found is that no matter how you mount the bikes the pedals find there way through the rack and can rub against the paintwork !

Keep us updated with your progress as if I can improve on my cheapy rack then so much the better.

 

[peterd51]

Hi,

I've not measured it and it could come down to making up the top rails and trying them out before adding more metal, but I reckon that with the tailgate slightly open I can hook the carrier over the top. I'll figure something out once I get started, the drawing it just my first ideas.

As for rubbing paint off...

it's a 1999 Mondeo, previously written off and repaired before I bought it. The front bumper came off a red car and the old colour's starting to show through the scratches. It has 186K on the clock and I welded roof-rack brackets to it...

I'm not that bothered about the odd pedal ding on the back :-)

Regards
Peter

 

[peterd51]

Hi,

well I made a 'hook' to try it out but I wasn't impressed with it...



It was easy enough to slip and and off but I hadn't realised that the top part of the hatch is so flimsy that it'd bend even without the weight of the bikes on it.

And with the back window being glued on I reckon it'd break the glass pretty soon.

So I'll give the earlier suggestion a try... brackets attached to the tow-hitch and slip the rack over the top.

Something like a 'H' maybe.

Regards
Peter

 

[peterd51]

Hi,

to make the bottom bracket I cut a piece of 1" box to 17" long with 45 degree angles at each end. Then I cut a couple of 'pins' 5" long out of 20mm box, tapped the pins into the bracket at 90 dgrees and welded up, I got this:



Next I drilled holes to line up with my tow-hitch riser plate, there's two 'spare' holes near the top. I made the outer hole in my bracket slightly bigger to take a piece of 1/2" pipe as a spacer and after spot welding this spacer inside the bracket I spot welded a washer over each hole.



next I made a backing plate with suitably spaced holes, washers and nuts spot welded on.



The uprights are 42" long 1" box with a couple of 20mm box 'pins' set about 19" up. I then made a stabiliser bar, 17" long with a 1" box 'pocket' at each end to slip over the pins in the uprights. This should hold everything together when in use and allow a 'stand-off' to keep everything off the car hatchback but also allow me to dismantle the rack for storage. I plan to cover the stabiliser with pipe lagging/foam, etc.



I finshed off today by putting it on the car to try it. Two bolts to fasten the lower bracket to the tow-bar and everything else slips together. I have some 'R' pins but I've not drilled any holes yet.



Next, I need to get the out-riggers that'll hold the bike frames made and fixed, and depending how stable it all is I may need to add another bar of 1" box across the top,
possibly held in place by winged bolts to make it all solid.

Regards
Peter

 

[peterd51]

Hi,

today I added the sticky-out bits that the bikes will hang on, set to an upwards angle of around 10 degrees. The stregthener strut was interesting as it was a 45 degree cut at one end but something else at the other. I managed it by putting a 5mm spacer at the 'back-end' of the chop-saw clamp and it worked out about right.



The bike frame holders started out as 40x3mm about 100mm long and I folded them to a 'U' in the press (not had chance to use it much recently!). The jig was made originally for 4mm plate so the pieces weren't quite 'square' but I eased them into shape in the vice.



And with one pair of 'U's attached I tried my bike on the back of the car.



the bike's possibly a bit higher than I though it would be so I'll probably chop about 1 - 2" off the bottom of the main uprights. That way the stabiliser will move a bit lower, away from the glass, as it does distort the panel when I use the ratchet strap.

I've already added the other 'U's and I just need to drill holes for the 'R' clips and paint it all blue. I reckon some rubber matting or foam cut to size and glued in the 'U's will stop the bike fames being damaged.

Hopefully we'll get a bit of sun soon and I can take the grandkids and bikes for a run out.

Regards
Peter