Z3 Punctures - Previously published in the BMWCC Magazine

[Mike Fishwick]

ULTRASEAL TYRE SEALANT - A Z3 OWNER’S EXPERIENCE
Mike Fishwick

While punctures are now far rarer than they were say, thirty years ago, they remain one of the most common problems which afflict the motoring public. Of course BMW claim that they only occur every 93,000 miles, this being used as justification for the absence of a spare wheel on the M Roadster etc. To give any odds at all on a random event is something which no self-respecting bookie would ever dream of! My experience has been that punctures can occur at any time, and occasionally in pairs – all that one can guarantee is that they will usually take place at highly inconvenient times.

At least the fitting of an orthodox spare wheel will cause little inconvenience, unless another puncture occurs before a repair has been made. Use of an ‘Emergency’ spare is not a complete answer, as their narrow tyre will restrict one’s speed to about 50 mph, reduce cornering and braking capabilities (particularly in the wet) and require the traction control system to be disabled if used on the driven wheels. One wonders why such devices were ever made legal, as when compared to a ‘real’ spare wheel they provide little benefit, except to the car manufacturer!
Even with their obvious disadvantages an ‘Emergency’ spare is better than nothing, but in the case of Z3 owners another problem then occurs – that of where to put the punctured wheel. BMW of course provide full details of fitting the spare, but are somewhat reticent about what one should then do with the ‘dead’ wheel.

Neither wheel will fit into the boot – even if it were empty – and it is therefore obvious that the white plastic bag provided in the toolkit is designed to protect the passenger’s legs from the heavy (and probably wet and dirty) wheel which must be carried upon them. Any travelling companion could be forgiven for doubting the wisdom of buying the ‘Ultimate Driving Machine,’ particularly if travelling across rural France on a Sunday, when all tyre specialists will naturally be fermé!

Temporary repair sealants, such as the M Mobility Kit and various aerosol-packaged products are not suitable for prolonged use, and they attach themselves tenaciously to the inside of the tyre casing. In most cases their composition is such that tyre specialists will refuse to repair a tyre which has been internally coated with such a sealant.

In the case of ultra-low profile tyres such as the ‘Z’ rated 245-40 X17 size used on the rear of the Z3 a flat tyre could be an expensive experience, as even a gentle stop from speed could cause severe damage to the sidewalls, not to mention the wheel rims. Remember that use of the M Mobility kit requires that the flat tyre is run even further, in order to spread the sealant around it before inflation can be attempted.

The answer to all these problems would obviously be that of puncture-resistant tyres, but in the absence of such wonders a good alternative is to coat the inside of the tyre with a sealant which will always fill remain sufficiently fluid to fill the puncture as soon as it occurs. It goes without saying that it should not disturb wheel balance, and be capable of being easily removed if necessary.

Several such products have been marketed over the years, mainly directed at the motorcycle market, and while most of them worked well, all had disadvantages. The usual problem was that after prolonged use at high speed centrifugal force caused the sealant to separate and so lose its ability to seal for long periods. This was coupled with extreme difficulty in removing the sealant in order to effect a permanent repair, so that – as in the case of the M Mobility Kit – a new tyre was the only effective answer.
Against this background Ultraseal appears to be the complete answer. It is not a new product, having been used in the United States for many years, and is approved by bodies as diverse as the US Postal Service, NASA, and the American armed forces.

It certainly seals well – I have personally attacked a motorcycle tyre with a spike until my arm grew tired, at the end of which pressure loss was negligible. After two weeks of such treatment by the public during a motorcycle show the tyre had more puncture marks than tread, but still maintained its pressure.

Ultraseal is claimed to be capable of repairing punctures made by objects up to 6-mm diameter for the life of the tyre, and in the event of a larger area of damage it will provide protection from rapid deflation. In such cases it can be easily washed out of the tyre casing, being water-soluble in its uncured state. Other properties include the ability to virtually eliminate pressure loss during long-term storage, and also to extend tyre life by up about 30% due to improved heat transfer from the tread area to the wheel.

Wheel balance is not upset, and it has been tested by Mercedes and Dunlop at speeds of up to 140 mph, after which it remained able to provide a permanent repair.

All things considered Ultraseal appeared to be the answer to a Z3 owner’s problems, and after a telephone call to the UK distributors in nearby Exeter (0870-2413730) my tyres were treated in about half an hour.

A measured volume of sealant – appropriate to the size of the tyre – was injected through the valve body, the small pressure loss being corrected afterwards. As I had been warned, the initial quarter-mile or so resulted in a strong imbalance effect which gradually reduced as centrifugal force spread the sealant over the inside of the tyres in a uniform coating.

On the subject of tyres I currently use Falken FK-451 which are wearing at least as well as the original Michelins, give better steering response, and only cost £348 for a set rather than £600!

Since then I have covered about 7,000 miles without problems in conditions as diverse as the afternoon rush hour in München, the incomparable Stelvio Pass with its 70-odd hairpin bends on each side, and autobahn running at up to130 mph. During this mileage no pressure loss was noted, and steering characteristics were not affected – in fact the only difference is that I now keep wishing for a puncture!

[Guest]

Since writing this article I have covered about 55,000 miles on several sets of tyres, all with Ultraseal in them, and remain very satisfied with both the sealant and Falken tyres - a pair of rear 245-40X17 recently cost £180, and usually last for a little over 20,000 miles.
I have had a few small punctures in that time, but never realised it until crawling under the car, but Daughter survived a trimming knife blade being inserted into a rear tyre of her Golf GTI. Our family would not be without Ultraseal in any of our cars.
Some people say that they would 'like to know when they have a puncture' but this strange pastime is easily done by nit using Ultraseal!
I would add that Ultraseal is not a licence to neglect your tyres - keep an eye on them, check the tread area for foreighn objects and remove them, and above all else be kind to your tyres.

[Larri]

Mike, very informative thanks!

Having suffered puncture after puncture on my bike (and I've yet to come across a bike dealer that will repair the buggers - so this involved new tyre every time at £100+ a pop ) I will be looking to have my tyres Ultrasealed if at all possible...Cheers!

[Guest]

Dear Larri,

You should not have any problems with your bike after Ultraseal is in the tyres - but make sure thay have recently been dynamically balanced, as motorcycles are a little more prone to balance problems than cars.
My other pastime is being Technical Officer for the BMW Club (motorcycles) and I know that many of our members are now using Ultraseal with complete satisfaction.
I do however have a friend who tells me that his tuned Honda megabike suffers frm a little Ultraseal-induced vibration when accelerating hard FROM 170 mph!

Mike F

[Larri]

I do however have a friend who tells me that his tuned Honda megabike suffers frm a little Ultraseal-induced vibration when accelerating hard FROM 170 mph!

I'm quite sure my bog standard 600 won't have the same problems

['MC' MarkC]

Mike Fishwick wrote:

Even with their obvious disadvantages an ‘Emergency’ spare is better than nothing

Mike; I recently heard that 8/10 insurance companies DO NOT COVER you/your car while you are driving with a space saver !

Not sure of the source, so I don't know how accurate/biased etc the survey was. If there's anybody reading this who's vehicle is so equipped (or they're considering purchasing such a vehicle), it could be worth a phone call to check !

[TonyCal]

Just done an internet search on ultraseal and there are DIY kits available. certainly well worth thinking about doing. IMHO.

[ZZZEMMCO]

Tony, sure the DIY is fine-But, when one contacts the area reps, they check car model, tyre size and make, before they visit .Then they work out ratio of mixture content and quantity for that tyre.Too much could affect balance of wheels.So for me, not worth any doubt of everything correct from Go.

[TonyCal]

And you have come back if it goes wrong
point taken

[CTB]

Z3's with 17inch wheels take 18 units of solution according to there web site, that means 3 bottles at a cost of approx 70ish pounds, I contacted the local agent, got his number from Yell.com (just type in Ultraseal) and he quoted £72 that included the costs of him travelling 30 miles to my house. He also said that if I was able to encourage a few others to have it done at the same time, he would then offer discounts.

£72 cheaper than the price of a new tyre, all I need do now is convince her who holds the purse strings ............................

[ZZZEMMCO]

Chris, a lot less expensive than that price, I think my ratio was 12-13%.Hope UltraSeal Will be at Gaydon in August ,at the BMW Car Club National Event.

[Robin]

Not sure whether to buy some ultraseal or to rely instead on the canister of gunk I have with my ///M to put in a tyre if it goes flat ?
Though bearing in mind the adverse effects on a car's handling when a tyre starts to deflate, then maybe prevention is better then cure.
I mean only realising your tyre is nearly flat when your car decides to be 'unco-operative' going round a bend at speed is not a pleasant experience

[RB007]

I just goggled Ultraseal seems to be lot of links? Who is the official dealer?

[Gazza]

I dont know if there is an Official Distributor in the UK, seems there were some legal goings on a while back regarding Official and Unofficial Ultraseal.

I've just had mine topped up to the correct amount. The Guy was mobile and charged £50 for all four tyres but he only does the East London area.

I had previously bought mine from Ebay, the twin bottle kit which isn't enough to do all four tyres.

It has been stated before that Ultraseal isn't suitable for our profile tyres, this Supplier had a book of tyre sizes and mine were listed .