When are Open Pro rims worn out?
Comments
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andrew_s wrote:
Shimano brake blocks?freehub wrote:I wish I got 20,000 from mine, only got 3000.
Yea, I used the crap ones that you don't need cartridges for. I'm hoping my wheels will last loads longer though as now after every wet ride I sand the blocks and fish the metal out with a knife, don't tend to do that after a dry ride though.
I am thinking of getting some koolstop but they apparently wear quicker, I want to best price/performance/lesswear really.0 -
John Stevenson wrote:Chris Juden of the CTC recommends a simple proof test: inflate the tyre to twice its rated pressure. That will load the sidewall enough to break it if it's getting close.
sorry, but that is a ridiculous idea. Trying to induce catastrophic failure in that way goes against just about every engineering principle in existence.
If you are a development engineer engaged in destructive testing in controlled conditions - fine. If you are in your garage trying to establish if your rims are worn - utterly stupid, and probably dangerous....
remind me again - you are BR's editor, correct..??0 -
Just bought one of those gauges that andrew_s recommends - a lovely little tool, very cheap, and perfect for the job. I tried it first on a non-open pro rim and wonder whether wear in the box section matters or is it only in the section above the box where the inside and outside is parallel that matters? On these rims the worst wear was just on the place where the box section starts with a little shoulder on the inside - so I wasn't able to measure thickness there.
I don't like the idea of testing with a tyre at 160psi or more - what happens if you damage the tyre casing as a result and get a blowout on a fast descent?
In future with new rims I will measure the average rim thickness eg 1.5mm and the overall rim width when new. Then I will monitor the overall and ensure that it doesn't drop by more than say 1.5mm - this will then even take into account wear on sections inside the box assuming a constant thickness of material.0 -
redddraggon wrote:Did you not snap a chain that weekend too?
Nah, that was a different day.
Have upped the bike maintenance a bit since all of this..!0 -
normanp wrote:Just bought one of those gauges that andrew_s recommends - a lovely little tool, very cheap, and perfect for the job.
Did you buy it from hswalsh.com - http://www.hswalsh.com/Tenth_Gauge_.aspx?i=TG22&t=37 ?
What else did you find to buy at the same time to meet their minimum order price of a fiver? I'm struggling to find anything I'd want, unless I decide to take up jewellery making.0 -
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My open pros have already failed and they havent even been used yet
. Will be sending those back lol Ribble Gran Fondo
Focus Black Hills
Raleigh Chopper0 -
Sorry to be slow chrisonabike - yes I bought it from them and added a miniature pair of pliers - but should have chosen cutters for thos annoying tag ends when fixing sportive numbers to the bike!0
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My Open Pro rear rim blew last week-end - luckily I wasn't riding the bike - a piece about 40 cm long bowed out by about 8cm. Inner tube blown of course but tyre was OK. I conclude that my measuring did me no good (see earlier post)! The wheel had done about 17000km of winter riding with Dura-Ace brake cartridges.I am moderately good at cleaning the rims & blocks after a wet ride - but didn't always bother. I don't feel I had enough out of these wheels! The wheels remain perfectly true (built by SJS) & the XTR hubs are great for a later re-build. The rims were noticeably concave - was this wear at the centre, or the edge pushed out by the tyre bead (or both)? I wonder how concave is acceptable? This could be a useful indicator...
I have replaced these with eyeletted DT Swiss 1.1 again from SJS, with Kool Stop salmon blocks to try to moderate wear!0 -
Mild concavity (less than 1mm) is wear, but shortly before the rim fails the top edge does start to get pushed out by the tyre bead, and the concavity becomes much more pronounced. It's quite obvious when you feel the rim with your fingers.
I'd have thought that 17,000km wasn't too bad. I've had failure at less than 6,000, before the tyre that was new at the same time as the rim.0 -
my wheels are dave kane handbuilt mavic 32 spokes with 105 hub and open pro rims , at what mileage should I just have the rims removed and replaced ? Ive done 4000 miles this year , should I use a ball park figure of around say 15000 miles ....or less ?
Jimmy0 -
It will all depend on what conditions you ride in. I expect my summer bike rims to last for ever (nearly). The winter ones do about 4000 to 6000 miles but I do live in the Yorkshire Dales which have a lot of hills and muck on the roads.JimmyK wrote:my wheels are dave kane handbuilt mavic 32 spokes with 105 hub and open pro rims , at what mileage should I just have the rims removed and replaced ? Ive done 4000 miles this year , should I use a ball park figure of around say 15000 miles ....or less ?
Jimmy
Just keep an eye on the braking surface and if it gets to 1mm concave you should be looking to replace it. You usually get a bit of brake judder before it fails. If you do when out on a ride let some pressure out and ride home with care.0 -
Some interesting observations in this thread, notably on the diverse mileage range expected from modern rims.
Anyone getting 10,000 miles from a rim are to be applauded - careful in braking, and diligent in checking braking surfaces.
My habit is to mark, with a laundry marker, on the inside of a rim,on wheels that I have built, the date on which I built a wheel and then check annually, with a digital caliper to note any differences.
Key to getting a good mileage from a rim, is to at least once a year, clean the braking face of the rim with 00 guage wire wool.Common sense in an uncommon degree is what the world calls wisdom0
