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[Hops128i]

I know this in an old article about 3g rft's, but there was a quote I found interesting:
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http://blogs.automobilemag.com/65212...ire/index.html
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"Perhaps most importantly, the 3G’s behavior is so similar to that of conventional tires that Bridgestone is willing to recommend this tire as an aftermarket replacement for vehicles that originally came with traditional tires--and have tire-pressure monitoring systems, which were made mandatory in the United States beginning for the 2008 model year. In the past, the company’s runflats have been installed only on vehicles whose suspensions were specifically engineered by their makers to minimize the effects of the shoes’ stiff sidewalls and additional weight."



My comment:
So, it seems the direction of rft development is toward a tire that behaves like a conventional tire. What does that mean if our car's suspension is 'tuned' for older rft's? I've read where people switching to non-rft's have found the handling a little off, and re-tuned the suspension.

And, if this suspension tuning to the tire is a big deal (not sure if it really is myself), then I would think OEM RFT equipped cars of the first few generations highly undesirable in a few years as rft's progress to being more like conventional tires.

[Tom K.]

While I don't think the suspension tuning is that critical either, I understood that a special rim was necessary for run-flat mounting which would seem to preclude a retrofit as Bridgestone suggests. Has that changed?

Tom

[Gary@TireRack]

The special rims are called EH2 (extended hump) rims. Google searches turn up many links, this is just one site.

[Gary@TireRack]

The EH2 wheels just have the extra 'hump' to keep a runflat tire in place when it's running on no air.

That feature won't matter with standard tires since you're not going anywhere with a flat.

[Tom K.]

Originally Posted by Gill@Tirerack.com

The EH2 wheels just have the extra 'hump' to keep a runflat tire in place when it's running on no air.

That feature won't matter with standard tires since you're not going anywhere with a flat.

Thanks for the link, Gill. So (for those who want to retrofit) is it then true that run-flats may be mounted on non EH2 rims, but they might not stay on the rim when completely deflated?

Tom

[Gary@TireRack]

Originally Posted by Tom K.

Thanks for the link, Gill. So (for those who want to retrofit) is it then true that run-flats may be mounted on non EH2 rims, but they might not stay on the rim when completely deflated?

Tom

Completely accurate.

[Hops128i]

Originally Posted by Tom K.

Thanks for the link, Gill. So (for those who want to retrofit) is it then true that run-flats may be mounted on non EH2 rims, but they might not stay on the rim when completely deflated?

Tom

Wow! I'm glad I'm reading this, I have Sottozero 210 rft's ordered at tirerack waiting for out of stock Elbrus i06 wheels. Need to find out if these are non-EH2 rims!

[aerobod]

Originally Posted by Hops128i

Wow! I'm glad I'm reading this, I have Sottozero 210 rft's ordered at tirerack waiting for out of stock Elbrus i06 wheels. Need to find out if these are non-EH2 rims!

If they are EH2 or EH2+ compatible with current RFT tyres suitable for use on a BMW, it will be embossed on the wheel similar to, for example: "8 x 18J EH2+". AFAIK most aftermarket wheels currently sold are not EH2 or EH2+ compatible.