CSR 15-inch rear wheels/tyres on an S3?

[Alaskossie]

 

Does anyone have experience with installing the 15X9, ET30 rear wheel/tyre combination offered on the CSR onto a late-model (new) Series 3 with deDion/Watts link suspension?

 

This would be the Caterham 10-spoke anthracite rear wheel with Avon CR500 tyres in 245/40 R15 size. (Caterham refers to this as a “255/40” size, but Avon doesn’t make the CR500 in a 255 size).

 

I have dry-fit this wheel/tyre combination onto my car, and it appears that there is about 1/2 inches of clearance between the tyre sidewall and the rear Watts link tube, which looks to be sufficient -- but my Caterham dealer says that there should be 3/4- inch clearance to allow for lateral movement of the deDion tube under hard cornering, with resulting contact between the Watts link tubes and the tyre sidewall.

 

That seems like a lot of anticipated lateral movement of the deDion tube...

 

Anyone out there having some practical experience with this wheel/tyre combination on a Series 3?

 

 

 

Alaskossie

[Irrelevant]

Alaskossie: I was thinking of trying this myself so would be interested to hear if it works. Please let me know if you try it.

 

BTW - not sure what your dealer is on about with DD tube movement . . I'd have thought the 3/4" clearance was more for tyre deformation. The DD may move a small bit due to bushes, but surely not that much You can always space the wheel a tad if it's that close.

[Alaskossie]

Adam,

 

The sidewall on a 40-series tire is so shallow, and the Seven is so light, that I was not anticipating the tyre sidewall would deform very much from cornering forces. I think any rubbing by the tyre during cornering would probably come from a combination of sidewall deflection and DD tube lateral movement against its bushes.

 

I was advised that the reason CC's assembly manual directs the builder to position the rear, short Watts link arm with it waisted or clearanced side toward the body (instead of outward which would be more logical), is to avoid fouling the body with the Watts link during hard cornering while hitting a bump, etc. So there must be some lateral DD/suspension movement of some kind going on during hard cornering.

 

The front Watts link is of course directed to be installed with its waisted side outward, to give extra clearance for the tyre. It would be nice to have that extra tyre clearance for the short Watts link arm also.

 

 

Alaskossie