Hitchcocks Forum

We have had 2 Carberrys crash in the last 2 weeks on the Round OZ V Twin Challenge both with reat tyre failures. The second one a couple of days ago had only done 150ks on a new tyre. They are carrying a fair bit of camping gear but I don't think this should cause the problem. Any thoughts?

Hi Norm,

What sort of failure do you mean and type or wheel and tyre details would help some attempt at diagnoses. Tubed tyre?

Regards Trevor

What's a Carberry? I have Googled and it seems to be a bakery!

Chris copy and paste this link http://carberryenfield.com.au/

I want a carberry engine, seriously looking at Carberry photos the front engine mount looks a bit flimsy, but then I would assume it has been tested to destruction...still want one though!

Thanks for the info. It's new to me.

Hi Trevor,
Info is a bit sketchy as both crashes were a long way from here but from what I can gather they were most likely Avons, if not I appologise to Avon. One bit of info I got yesterday was the valve was missing from the tube on the second one to me indicating rim slip and this may be a result of something put on the rim/tyre when it was fitted the day before. The first one had a puncture a couple of days before the blowout and it could have been a result of similar fitting, and as the rider (RECOA Club President) suffered severe injuries including 15 rib breaks, little has been given out as the bike was picked up and returned to Sydney and most concern had been around Bruce's recovery

Hi Norm,

Commiserations to the injured riders and we all wish them a full recovery.

Rim slip would be my first guess and perhaps the Carberry simply puts out too much torque.

Even with standard 500 power, my dealers mechanic always loosened the nut at the bottom of the valve stem, warning that if it was tight, the valve would simply shear off if the tyre slipped.

Maybe this could happen if the tyre was a bit soft. Mr H sells a tyre security bolt, worth fitting and I will do the same when my rear tyre needs changing.

Cheers Trevor

Hi Trevor,
Many discussions going on about rim locks and valve nuts out here at the moment, all it can be.

Hi Norm. Another possibility is that the inner tube was caught under the tyre bead. This causes the tube to puncture after a short while. It can sometimes cause the tyre to lift off the rim where the tube immediately explodes and the tyre lifts off, you don't always realise that has happened after the accident. I have actually had this happen...I was two up and travelling at nearly 60MPH. After the explosion, I had to fight the bike for a hundred yards or more as it shot sideways left and right and then careered along the kerb with me yanking the bike up and footing the pavement like crazy to eventually stop with several pedestrians coming over and applauding the feat, My passenger was absolutely amazed we stayed on the bike as at one time it was nearly horizontal and at 90 degrees sideways then flipped over the other way until the bike ran along the kerb, trying to flip us off, before I managed to stop it. That was some terrifying experience! Ever since that time, I always triple check for that mistake whenever I fit a tyre.