sham

tyre upsize maths, different from the sticky

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Hi all,

My bridgestones have some life left in it so thought I will change them for new ones. I also want to upsize it and here comes my question on it

My Punto comes with 175/R14 (Emotion), and I can upsize it to 195/R15 but E+ comes with 195/R15 by default and it generally is upsized to 205/R16 , So if my understanding is correct then my 175 can be upsized to 205/R16 too isn't it?

Please let me know.

Also other questions include

1.) wider tyres better than slender ones?( I know of wider ones causing hydroplaning effect on water logged roads)

2.) Is a length of the sidewall more important for the grip than wider tires.

3.) I want more grip and a bit softer ride(a bit of tyre noise percolates into the cabin in BS) than my existing ones.

PS:: I'm satisfied thoroughly with BS and planning on buying the same, but want to give others a shot as well.

Surprisingly my BS lasted for nearly 40k it still has about 3mm, But i think it would be risky to continue with it anymore as its old.

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Even I am planning to replace my tires for my Punto although I have the E +. I plan to go in for 195/R 15 since I feel its more than sufficient. You have a good balance between grip and ride quality with 15 inch rims. I am not sure how much the ride quality will be effected if you go with 16 inch rims as you would be going for lower profile tires.

For a softer ride, better grip and lower noise give Yokohama a chance. The C drive should suit your needs perfectly. Just my personal opinion as I have had a good experience with Yokos.

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Tire upsizing needs to be planned carefully if your car is running ABS and EBD, in such a case the calibration can go haywire and hence upsizing of tire without upsizing on wheel rim is the best bet.

That is keeping the rim dia same keep the tire aspect ratio same only go for wider foot print.

This will not change the over all dia of the wheel nd tire.

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Tire upsizing needs to be planned carefully if your car is running EBD, ABS, going for a wider foot print keeping wheel rim and tire aspect ratio same is the safest bet.

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Yes my car does have ABS/EBD however if the ABS is not tuned separately in the E+ as against E , then I can get the 15" wheels, besides this is the first time I'm hearing about ABS issues if i upsize it by just 1".

I mean I'm aware of the consequences of heavy upsizing but something like 195/R15 should not be a huge issue I guess

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Go for 205/55R15 tyres and get a new alloys of 15" and 98 PCD (very rare) . Don't upsize to 16" it is not worth it . Also the callibration of ABS depends on the tyre grip etc but in case of popular cars one can safely do a +1 upsize and the callibration won't get that much affected also I think FIAt uses the same module for the E+ and E varient so you can easily go for 105 R15 . 

The old swift ZXi and VXi (ABS optional)  had different tyres but same ABS system (3 channel one ) . The Ritz's ABS is poorly callibrated because it cut in much before the tyre grip gives up .

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Thanks for the response. 55 seems quite low to me, I'm looking for something in the range of 65-75, doesnt matter if its not 205, I am happy to upsize it to 195 also.

Just wondering if yoko C-drives are good or Bridgestones are better.

My main concern right now is with grip and tire noise(which is quite a lot in BS).

I read that C-drives have less noise and great grip, is that true?

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@sham

I suggest 195/60 R15, 5.5J or 6J. 98PCD. (tough to find, rightly said by rssh). Yoko C drives better in terms of noise. You can also look at Continental tyres.

Answers to your questions:

1. Depends on how you drive. High speed drives are better with wider tyres. City mobility is better with thinner tyres.

2.More grip often comes from better rubber quality, but width play a vital role too. Upsizing means wider tread and smaller sidewall. Both act together to compensate tyre diameter. Having one out of the two factors will be an incorrect upsize.

3. More grip and softer ride quality ? Better rubber with higher sidewall. (preferably OE), since downsizing is not recommended. Upsize will ruin ride, with better grip. Suggestion is 175 and the softest tyre available. Tyre life will be less though.

sb-alto2012-02-23 04:55:06

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@sb-alto : Any idea what the cost difference between Continental and Yoko C drives are?

Also, which one would have stronger sidewalls, I am asking this since I go through a couple of really rough patches everyday.

@sham:Sorry if I am hijacking your thread.

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sb-alto:: I know about continental being very bad in taking knocks.

One of my friend's really had a bad experience with continental(not to say that even I will but just being cautious).

At 30-40kmph he unfortunately had to drop down to the mud run off area on a hill climb and when the tire was suddenly taken from asphalt to mud the sidewall scrapped (the impact was not too high as he puts it) and it tore the sidewall completely.

I"m very satisfied with the road grip my BS is providing right now.

its BS-B250.

I just dont like it because its too noisy.

Now if i can get a tire with same or more grip but with less noise I'd be happy.

PS:: reason for pushing this thread is that my BS is almost out of juice and if i sell it now I could at least get about 2k per tire ;)

So my requirement is just this..

1.)Grip

2.)low tire noise

3.) no to low profile tires

Flywheel:: No issues , so long as we are discussing about tyres :)

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For low noise and good grip the C drive and michlein Primacy LC tyres are the best current in the Indian market . I would say go for the 195/60/R15 profile .

 

Also don't get confused with the xxx/55/Rzz profile . The 55 is the % of the xxx so a 205/55 will have more side wall than a 195/55 . Tyres can be found easily but your main concern should be 98 PCD rims . Also note that dealers will suggest you to go for 100PCD rims because they are damm popular but avoid then for safety reasons .

Go for 195/55R15 and try to find the OE punto alloy wheels aftermarket (98PCD)

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(Hit "post reply" a little too fast)

195 should be sufficient right, or 205. I understand that it can have effects on the steering, braking .

I primarily drive on good roads(well at least 70% of the times).

Highway driving is about once in 2 months.

Bad roads constitute to only about 15% of my drive

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Rssh:: Hmm.. I read about C-drives and they say it gives less grip in dry than it does in wet (weird). Also there are issues of steering going light after this change.

And for Michelin, looks like its really a soft tire(not too good for hard cornering).

Looks like we will be discussing about this forever and i will not buy anything. :(

(Sorry for that)

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My Opinion is that the C drive will give you better grip that the BS even in the dry. Yes C drives will still give you good grip in the wet because of the tread pattern.

Yes I read a couple of threads on another website about the steering going light I don't really think this should happen. It didn't happen when I put them on my old Swift.

I think the Michelin will be more expensive option as well. To me the C drives will be the perfect balance between handling ,ride and noise reduction.

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@Flywheel

Conti tyres are not bad, but they are poor in dealership and service. Yes, tyres are softer than average and provide good grips, but cannot take too much toil.

In comparison C drives are better in terms of durability. Conti have better noise control as well.

BTW,  Bridgestone launched a lot of new tyres, Please check Bridgestone India website >tyre pattern

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See if you want to corner hard then the S drive are the best but they are more louder than the BS (I mean loudest) . The Primacy LC and C drive have the best compromise on noise and grip . Also don't do hard conering with these tyres they are meant for comfort (ie less road noise and road aborption) . Go for the 205 if you want to be a little agressive on corner otherwise the 195 is more than enough.

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rssh:: As such i dont do hard cornering (even on highways) however I do tend to travel a lot on hilly regions with good ghat section roads.

Since I own Punto and it handles great I like to play around for a while before settling down. So when i do that I dont want the tyres to let me down.

Per se I drive like "L Boards" , I just love my car that I cannot tolerate any dents or scratches even if it means i get to a destination late. :) I only open the taps on highways

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hi. i drive a palio 1.2 l petrol with 165 80 R 13 tyres-a tyre dealer is suggesting using 175 70 R 13 size instead for better braking.willl this afffect my mileage also.i plan to switch to tubeless will i have to change my rims also

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