Team-BHP - Bulge in sidewall of one Runflat tyre. Please Help !!

Hi Members,

I have a year old BMW 320d (11000Kms done) with current setup of Goodyear 225/45/R18 91Y. I am facing huge issues with tyre bulge and have already got 4 tyres replaced. I am in Gurgaon and road conditions are terrible. Moreover the ride quality is also very harsh.

I had opted for M Kit upgrade and have got all carbon finish mirrors/spoiler/ grills and black 18 inch alloys. The default size is 225/50/R17 in 320d luxury line. I am in a battle with BMW over this issue and they are somewhat cooperating. Now I tried driving another 320d with normal 225/50/R17 and the ride quality seems much better.

Now from whatever study I have done, the issue boils down to side profile of the tires and maybe switching to tubeless will also not help but I am not sure.

Please I need suggestions from your experience to take a final call. I see following options:

1. Downsize to normal 17 inch alloys (BMW only has them in silver and this spoils the look of the car, Its white base with all black accessories)

2. Not sure if switching to some other brand 225/45/r18 RFTs will help incase Goodyear is the problem here.

3. Switch to tubeless and keep the same tyre profile, not sure if ride quality and bulge issue will get resolved given how bad Gurgaon roads are

4. Downsize to 17 inch and opt for after market alloys in black colour to retain the overall look and then get 225/50/R17 RFTS. I prefer RFTs somehow because of safety and comfort.

Thanks,
Rohan

Runflats actually are less susceptible to bubbles than regular tubeless, unless you hit big bumps/potholes. In your case I don't think tubeless will help. It will be best to downsize to 17" wheels with 225/50 tyres. I am sure you will find someone willing to exchange their set for free with you for the 18" wheelslol:

Contrary to the theoretical advantages of Runflats, I have heard of cases where Runflats repeatedly failing from regular city driving. Could be due to a bad production batch (these were continental made in Germany). Are you running on recommended tire pressure? Lower pressure will surely damage sidewall. Before you give up on your dream setup of wheels, do try normal tires preferably from Michelin. I have been running on 19" wheels (s class up from 17") on horrible roads. The ride really sucks no doubt but I am in the mood for big wheels so I am continuing with 19"s. I also drive carefully on bad patches which is common sense and maintain recommended tire pressure or higher, but never lower. If you want big wheels, you have to truly give up on ride quality so don't use lower psi for more comfort.

Off topic, it's better not to sell the original wheels when upgrading just in case you change your mind. You get peanuts for selling used wheels anyway.

Quote:

Originally Posted by Gilead (Post 1978350)

flyingspur, I don't have any suggestions that may help you here but I have a related question. A bulge on the outside wall can be seen easily, but what if there is a bulge on the inside wall? We'll just keep driving around and never notice it right.

Quote:

Originally Posted by ajmat (Post 1978361)

Well, air pressure inside the tube is higher so the bulge can only be one way

Gilead has a point: A Tyre has two faces of sidewall.
One faces the outside world, and the other faces the car internals like suspension, axle etc.

Any impact that damages the internal cords will produce the bulge. But what if this damage is on the side the facing the axle? One may never even come to know.
How does one come up with a fool-proof way of checking this?
I guess one has to develop the habit of scrutinizing the entire tyre weekly.