Alloy wheel load rating?

[dom_e]

I'm looking at a set of 17" alloy wheels, but they're after market ones, which I'm more wary of. They have marking on the inside, but it's not clear if any of these indicate the load rating. The image can be seen at https://drive.google.com/file/d/0B4dp11 ... sp=sharing

The top left of the image shows a 709 stamped, but no kg. Could this be the load rating?

Cheers

[helen&tony]

Hi
Most Alloys that I've seen are stamped on the rim. Bongo originals are usually 609. I'm told, now, by Rochford tyres, who were more than helpful when I started asking about load rating that most are 700 Kg rated, and I know that they usually have the same centre bore so you just get a set of rings to fit your hub. When I first started looking for replacement alloys, they told me it was hard to find some with the correct load rating, but that appears to have changed....makes sense, really, because by supplying a rim around that load rating, the wheels are suited to a wide range of vehicles.
I buy new alloys, as you can have absolutely no idea where the old ones came from...most likely from a scrapper, and thus exposed to stresses which would need the wheels crack-tested to assure that there's no damage!....There have been a few members on here who've had wheels fail!
Cheers
Helen

[Mark Elvin]

In reality the maximum load capicity of a wheel is normally at least twice the claimed safe working load, this allows for the wheels being kerbed etc during their life.

[dom_e]

Thanks for the advice. It seems like they may be an option then. Ideally, buying new would be best, but prices are pretty high (although what price can you put on safety I suppose).

[Mark Elvin]

In reality the maximum load capicity of a wheel is normally at least twice the claimed safe working load, this allows for the wheels being kerbed etc during their life.

I am nnot claiming however that your insurance company would take the same view.

[helen&tony]

Hi Mark
In that instance, Industry Safe Recommended Parameters are 2.5 times the calculated stress...and when you take into consideration the stresses imparted in cornering, hitting a normal bump in the road (excluding pot-holes), no ACCESSORY after-market wheel will comply with these regulations. I approached a firm who supply after-market wheels for vans with the loading of the Bongo, and it's carrying capabilities, and the wheels are specially made to cope...a set of rims for the Bongo in 15 inch were going to cost £1100.00 plus....frankly, I was sorely tempted!...It seems that wheel stress calculation is centred round static weight-bearing rather than anything else The standard Bongo alloy rated at 690 Kg is barely above a Bongo's static loaded weight, and Mazda seem to think that's right for some inane reason, but whether their wheels are O.K. by insurance assessors standards, I can only guess, as my parents had the distinct displeasure of dealing with an insurance assessor who had the brains of a pee-wit . Another thing worth considering, is that I was stunned to find that one set of my Bongo Alloys was correctly load-rated by Mazda Standards, but stamped PRC....and this was a wheel company that's had a good name since the '60s...I have bought their wheels in the past!....Now, the one thing I find hard to assess, is whether they have good manufacturing capabilities , as some Chinese firms are superb, and then again some aren't, even though they appear to be good. A point in mind is the silicon hoses we bought in the Bongo fraternity....The first batch were great, but the second lot....errr...best not go there
The Industry 2.5 standard was pointed out to me when I was buying fittings for tubing carrying 750 P.S.I. and I had to go for 1900 -2000 PSI...not hard to come across, and better to know, rather than go to a company who will sell on the knowledge of an untrained storekeeper....I REALLY like using companies where the "Old hand" knows what they're doing!
Cheers
Helen

[dom_e]

considering other options, I am wondering if running 16 inch wheels with 215/65 tyres would be okay? It would make the wheels a larger diameter and therefore the speedo slightly out, but it's there a safety or technical reason why this would be a bad idea?

I ask since it seems 65 profile tyres seem common on 16 inch rims.

[helen&tony]

Hi
For some inane reason, Mazda use wheels stamped 690 Kg as originals on a Bongo, so you could go and search a set similarly stamped. I 'phoned round , and e-mailed for a long time to find what I wanted, as I'm very fussy, and quite a few said they didn't supply anything suitably marked. I eventually came across a specialist supplier of van wheels who would make up some at £1100.00 as I said, and these were custom-made from solid!....I was going to get a set, but I decided to put it off 'till later.
When I first enquired, Rochford Tyres were extremely helpful, and said the 15 inch wheels were impossible to find in the right rating. They suggested going up in diameter as some of the heavier cars have large wheels, but I wanted the deeper side-walls to cope with the uneven pot-holed roads here!....When I enquired again, a year or so later, the same chap said all the wheels they sell were suitably rated. I have a sneaky feeling that as all the wheels now seem to be with a large centre-hole, and the wheels are supplied with spigot rings suitably sized , and the fact that they now state all their wheels are rated 700 Kg or thereabouts, that manufacturers are supplying for an all-vehicle suitability! Give them a ring and see what you can find...They are pretty efficient and have good deals, so I bought 2 sets!. Other suppliers weren't any too helpful, including some mentioned on here, who didn't seem interested in more than an odd e-mail. Rochford's service was extremely good, with several e-mails a day.
Another point to remember, is that buying second-hand is risky, as wheels are often from a breaker, and there's no telling what excess stresses were imposed on the vehicle. There were reports in the 60's - 70's of how second-hand alloys were often found to have cracks and faults when x-rayed. Kerbing can even damage an alloy more than you can see!
Good Luck
Cheers
Helen

[dom_e]

Thanks for the advice again. It's around £100 more for new than used, which is probably worth it.

[helen&tony]

Hi
Yes...£100.00 extra is well worth peace of mind!
Another pointer worth noting, is the wheel design...many small spokes make for a more secure wheel than four or five thicker ones, if you think about it logically...much like spokes on a bicycle...there being only small areas of unsupported rim...
Cheers
Helen

[dom_e]

That's well worth noting. More difficult to clean though

[helen&tony]

Hi
Karcher, or a bucket and wheel brush...I use either, depending on mood
Cheers
Helen