Trailer tyres

[Colin Morley]

I am not an expert on trailer tyres but thought I would share my experience with you so you have more information than I did.

Three weeks ago I was towing my BR on the M25 at 60 mph when a trailer tyre shredded. This did not cause a driving problem and I only noticed it when I looked in the side mirror.

Having a spare on the trailer I thought I would change it and soon be on my way. Unfortunately, The wheel brace for my car was too big for the trailer so I had to call out the AA. FIRST LESSON - have a wheel brace that will fit your trailer wheel nuts.

The AA duly put on the spare wheel and then asked me what was the torque for the wheel nuts. I did not have a clue. SECOND LESSON - the wheel nuts can be tightened to a torque of 65lb/ft.

The AA man said the problem the tyre burst was probably because it had been running too soft by the fact that the edges of the tyre where far more worn than the centre. He then asked my what pressure it should be inflated to. Again I did not have a clue. THIRD LESSON - the tyre pressure should be 36 PSI.

When I got home I was looking at the two wheels carefully and noticed they said the maximum weight was 375 kg. That freaked me out because the boat weighs about 450 Kg + gear + outboard is far more than 375. FOURTH LESSON - 375kg is for each tyre so the trailer wheels can carry 750 kg.

The last pieces of information is the 145 / 10 wheel and tyre that is fitted to my trailer has a load speed rating of 375kg at maximum 140 kilometers per hour (~80 miles/hr).
The trailer with a spare wheel fitted weighs approximatley 245kg so with the 450kg boat it should be within the 750kg limit.

I have learned most of this from CLH trailers who have been very helpful.

I hope this helps you if you are just getting ready to go trailing and sailing.

[Andy Dingle]

Many thanks for this post Colin. Some excellent advice which I will certainly take on board.

I was interested when you said the tyre shredded without causing a driving problem! Would certainly have caused me a certain amount of consternation in the part of me sat on the driving seat had I seen that in the rear view mirror!!

Thanks

Andy BR12 Psalter

[Jeff Curtis]

I think 65lb/ft may be overdoing it for the small nuts on most of our trailers. My Indespension catalogue gives the following values all in lb/ft.

3/8" UNF - 42
7/16" UNF - 50
1/2" UNF - 56
5/8" UNF - 85

And for bolts
M12 -  55
M14 -  60

10" wheels tend to use 3/8" nuts or M12 bolts

I learnt the hard way about over-tightened wheel bolts many years ago when bringing home a new-to-me Drascombe Lugger. The previous owner had done such a good job of tightening the wheel nuts that one wheel slipped its studs at 40MPH, crossed the carriageway and disappeared into a field. I did find it eventually but my new-to-me boat had to go home on a recovery truck. It was a braked trailer and the stripped studs cost me a pair of brake drums.

[Colin Morley]

You may be right but the number I quoted was from the Trailer Manufactures CLH.

[Tony]

Photo below shows what happens to trailer tyres if you under inflate on a long journey.
This wear was caused at 32psi (recommended by the makers) over two trips to Greece and back with my Cardigan Bay lugger, "Four Sisters",  with a trip to the Morbehan in between – a total of about 6,000 miles. I now pump the replacements  up to 36 psi and have had no further problems over the subsequent four visits, although she does skip about a bit over the bumps if you are towing her empty!
This year will be my last drive out to Greece until the ferry prices come back down to something reasonable again. I’m towing  out "Wabi" ( my hybrid Deben Lugger ) and leaving her there in the care of a local boatman, so it’s back to EasyJet next year, worse luck. On the plus side I get an extra 8 days sailing .....and the accommodation is paid for by the saving on ferry costs ...which is nice.

Hint: If going abroad, now looks like a decent time to buy Euros. Down to 80p and holding.
(However, Sods Law dictates that if you buy now they will drop to 75p by August and if you don’t buy now they will bounce back to 86p !)

[Colin Morley]

Hi Tony,
Thanks for the photo. The bits of my tyre that were not shredded looked like that. I now have them pumped up properly.

Enjoy Wabi in the Ionian. I think you should charter her to your Swallow boats friends when you are not using her !!

[Tony]

Enjoy Wabi in the Ionian. I think you should charter her to your Swallow boats friends when you are not using her !!
[/quote]

That's not a bad idea! 
The only other sailing boats in Lakka harbour are a Drascombe Longboat called "Dorothea of Gaios" and a Drascombe Lugger (originally one of the hire boats  that Sunvil had on Lefkada, I believe, now in private hands.) Any friends of Matt  on Paxos this August are welcome to come for a sail. If you see "Wabi" in the harbour leave a message at the nearest Taverna!

[Graham W]

Here's a picture of one worn tyre, next to its radial replacement.  I estimate that I have only done about 5,000 miles on the original tyres, kept at 36 psi, so the amount of wear is surprising.

[Llafurio]

Here's a picture of one worn tyre, next to its radial replacement.  I estimate that I have only done about 5,000 miles on the original tyres, kept at 36 psi, so the amount of wear is surprising.

The tyres on the standard CLH BR20 trailer are fierce small, and are at their rated load limit (375 kgs), so one should not be surprised at their actual wear. My guess is they are just 2/3 diameter and width of a proper medium size car tyre, which explains their relatively excessive wear. I doubt they are fit enough for the job if you travel long distances with your BR20, and some of that on poor roads.

[Graham W]

Citius, amplius, asperius!

The only poor roads that I drive on are in mid-Wales.  Everything else is billiard smooth, albeit heated by the sun to temperatures not seen in the UK since 1976.

[Graham W]

I have posted an article on 'Towing your boat' in the library.