Narrowest tyre on Kahn RSR 15x6.5 rims?

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Narrowest tyre on Kahn RSR 15x6.5 rims?

StoneNewt

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As the title states really, also why doesn't anyone seem to think that the 15x5.5" rims fit on a Punto Mk1 or Mk2? And if they would, could anyone tell me the thinnest tyre I can put on those? I'm aiming for 175/60R15, though it's not overly low-profile, it is a tad narrower side-wall than the 195/55R15 my local alloy supplier said was the best for the 15x6.5" rims.
 
Why would you want 15x5.5" rims though.

The best tyre size for a 15x6.5" rim would be 195/45s.

If you want proper narrow sidewalls get 185/45s or 175/50s.
 
chrisunoman said:
Why would you want 15x5.5" rims though.

The best tyre size for a 15x6.5" rim would be 195/45s.

If you want proper narrow sidewalls get 185/45s or 175/50s.
Why 5.5" wide rims? For thinner tyres perhaps?

Best tyre for what? 195mm is a little to wide for a 60 I think, you lose to much power to rolling resistance. Also195/45R15 gives me a 557mm total dia, which equates to a ~3% ratio hike (I'm running 175/60R13 right now), 175/60R15 (591mm dia) gives me ~9.5% & 185/55R15 (585mm) is ~8%

I'm not looking for narrow sidewalls, I'm looking for a ratio hike & a better look to the stock steel rims.
 
StoneNewt said:
Why 5.5" wide rims? For thinner tyres perhaps?
Personally i dont get why you want thinner tyres, and do kahn 15x5.5" wheels exist? :confused:

StoneNewt said:
Best tyre for what? 195mm is a little to wide for a 60 I think, you lose to much power to rolling resistance. Also195/45R15 gives me a 557mm total dia, which equates to a ~3% ratio hike (I'm running 175/60R13 right now), 175/60R15 (591mm dia) gives me ~9.5% & 185/55R15 (585mm) is ~8%
If your stock tyre is a 175/60 13, and your upgrading to 6.5x15s, then you want a 195/45 15.

The speedo would be up by 1.8mph, but seeing as speedos are very inaccurate and set slightly lower anyway, then this is negligable.

StoneNewt said:
I'm not looking for narrow sidewalls, I'm looking for a ratio hike & a better look to the stock steel rims
Now im lost. Your after getting new tyres for your stock rims? That give a ratio hike? Why are we talking about 15s then???

If you get some 175/60 15s on your car, then your speedo will be up by nearly 6mph which imo is too much.
 
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chrisunoman said:
Personally i dont get why you want thinner tyres, and do kahn 15x5.5" wheels exist? :confused:
Wider tyres may produce more grip however they also have a higher rolling resistance, going from 155 to 175 tread width has already given me better grip, now I want to increase my gear ratios. Kahn Wheels seem to think 15x5.5"exist, right now I've got 175 tread width tyres and it's just about right imo...

If your stock tyre is a 175/60 13, and your upgrading to 6.5x15s, then you want a 195/45 15.

The speedo would be up by 1.8mph, but seeing as speedos are very inaccurate and set slightly lower anyway, then this is negligable.
Stock tyres are 155/70R13 making the speedo slightly faster than normal, why are we talking about mph? speed differences will be in % no? As stated before 195mm is wider than I want to go.

Now im lost. Your after getting new tyres for your stock rims? That give a ratio hike? Why are we talking about 15s then???

If you get some 175/60 15s on your car, then your speedo will be up by nearly 6mph which imo is too much.
I want to replace my 13" steels with 15" Alloys, putting the 15" equive of what I've got on now to..
a) keep similar grip & ride characteristic
b) give me a nice ratio hike
and YES the whole point is to push the gearing up, from what I understand I can do something about the whole 'speedo is out' thing...
 
StoneNewt said:
Wider tyres may produce more grip however they also have a higher rolling resistance, going from 155 to 175 tread width has already given me better grip, now I want to increase my gear ratios.
The rolling resistance of a tyre depends on the size of the contact patch, and as a rule of thumb low profile tyres have a higher void ratio than 'standard' tyres meaning that the size of the contact patch remains largely unchanged. That is why in my opinion a 195/45 15 tyre would be best.

If you wanted to stick with 175s then get 175/50r15s, not the 60 profile.

175/60 15s would look ridiculous, have poor stability and poor steering response.

StoneNewt said:
Stock tyres are 155/70R13 making the speedo slightly faster than normal, why are we talking about mph? speed differences will be in % no? As stated before 195mm is wider than I want to go.
My apologies, i forgot the mention the speed differences i stated were how much the speedometer would be out when travelling at 60mph.
 
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