Braking surface wear on rim

[Guest]

Hi Guys

A prosperous New Year to all and may that special dream (or achievement) come true this year. Mine will be a sub 4hour Argus ( my first ) I managed a 3h40 94,7.

I have Campag Atlanta 36 spoke wheels on my Tandem and they are performing very admirably. Is there any way to determine the wear on the braking surface of these rims as there is no machined wear indicator groove. I have no history on these rims and do not want the rim to disintegrate at 90 km/h!!!!!!!!

I also heard of a stone (pumice????) that one can use to break the polishing on the rim, Where can I get one of these stones. I have alway been cleaning rims with a 3M scourer and it works quite well. Will I be able to use the fine stone on my Lansky Knife Sharpening Tool????

Lastly, I read the facinating article about weight of compnents with a smile. If you guys are recreational cyclists like me with a bit of a boep (tummy for the Aussies not used to braai and beer!!!!!) you just need to loose a kilo or five in weight and voila you have one of these new fangled super light racing bikes and if you keep on losing weight your bike might not weigh anything at all ;D ;D ;D ;D

Keep those wheels rolling

Big H

 

[Guest]

Hi H,
I'm not sure what to suggest about this. Perhaps measuring the rim wall thickness with a vernier/dial/caliper occassionally? And comparing it to the thickness of the rim walls when new.
Trouble with that idea is that the tyre will need to be deflated :-(
Replace rims when 10 or 20 percent wear is evident? Maybe a good visual inspection, and rely on your gut feeling.

I've read reports of tyres blowing out at speed, on tandems.
Usually attributed to rims overheating, also rubber rim tapes failing due to the heat, and allowing the spoke to puncture the tube. But spokes shouldn't be protruding past the nipple anyway. All up, it's a very rare event.

I've only recently woken up to the existence of better rim tapes, 'Velox', cotton, with some adhesive backing. Very good, they are. You don't need to stretch them, just lay the tape gently on the rim. Beats my electrical insulating tape hands down.

You might be able to search the archives at
tandem@hobbes or hob ( not sure of the correct spelling here). This is a U.S. list, with a very high volume of messages. If you would like any other links, give us a hoi.
Cheers.

 

[Guest]

Willie

What are the dangers here ???? I have also had blow outs at speed. You just need to grit your teeth and do nothing quickly or erraticly. If the rims wears through under speed could the whole wheel collapse????? Will I have time to bail out. Going down a hill @ 85 km/h you do not like a thought like this flashing trough your head!!!!!! Other option is to BUY new rims. DRC rims have just been released here and glowing reports are coming in.

I use two rim tapes at a time on my wheels. Not sure about the name though, I think Hutchinson, but have used PVC electric tape in emergencies.