I have Paul Matty (I believe) repro Lotus wheels on my +2S which had new Uniroyal tyres on about a year ago. Ever since then, the darned things keep going down. Every time I go to use the car after a few weeks I spend 15 minutes with the foot pump! They never went down before with the old Goodyears that were on them. Anyone have any tips for stopping them from leaking? It’s irritating more than anything, but could do with sorting it…
Hmmm… thanks. I’ll look into it. Surprised the Goodyears didn’t leak. Maybe they had inner tubes?
Ps - like the sig - seen it in a few places - updated mine!
Pps - My girlfriend’s from Milan! Whereabouts are you? We bought an old '71 Fiat 500 in Milan the Christmas before last and brought it back here to the UK.
Pump up the tyres and then put some soap solution on the outside of tyre and wheel. Look for small bubbles forming in the solution.
If they form on the side wall of the tyre itself it is the inner butyl rubber layer in the tyre that is letting air by, only solution is replace the tyres or put a tube in.
If they form at the rim where the tyre meets the wheel then the bead seating area is either out of tolerance or needs cleaning up to ensure a good seal between the tyre and rim.
If its on the inside of the rim then it is porosity or other faults in the wheel itself
Hope this helps it should be able to fetect the source of a leak that takes around 3 weeks to loose tyre pressure. Iit does with my Hoosier street TD tyres which are designed as tubed but which I run tubeless and thus do not have a butyl rubber inner layer to seal the air in properly.
I had the very same problem with my alloys. The cause turned out to be the wheel itself (the bit under the tyre) which was covered in powdery oxide, flaking the paint off and ensuring a hopeless seal with the beading.
If yours are recent Paul Matty repros then this might not be the answer but mine started going down every three days so I’ve had them refinished and polished.
The wheels look good but the Dunlop SP10s I’ve ordered still haven’t shown up and the dreaded words ‘back order’ have been whispered!
I’d better leave the eurobox at home or Club Lotus won’t be pleased as my +2 is booked on the stand.
Si
Greg, I don’t have a solution but would just emphasise for the others here that don’t share our luck; the positive side of a small Italian girl as a passenger not upsetting the fine balance of the +2, my fianc?e is from Milan too…
If it helps your investigations I fitted a new set of Matty alloy wheels about a year ago and fitted the existing tyres (Goodyear Eagles I think). I have done about 5,500 miles since and have lost no pressure in any of them, so it looks like the wheels are ok.
Thanks to all for the replies! Really useful.
I’ll start work on this when I get back from my hols. Off to the Le Mans 24 Hour in about… oh… an hour and a half! Must pack!!
Here’s a little post scriptum for when you return - If you have the original Lotus alloys the edge of the rims are unusually far from the wheel centre which means the 13" tyres must be severely stretched when getting them off and on. In the hands of a nomal tyre fitter this can be a recipe for disaster as the beading is easily chewed off or cut into by their machine. This happened to me when mine were removed and I lost a tyre which had about 20 miles on it that I’d intended to use as the spare when the wheels came back from the refinisher. The beading on all the others was damaged too.
Enjoy the trip,
Si
Jason - the tyres have just arrived and it should be running by next week.
I have the orginal Lotus alloys on the plus 2 and have had similar problems over the years getting them changed due to the very shallow well in the wheel that makes stretching the bead over the rim difficult.
I now go to just one guy who knows how to do it (but does not like it every time he has to).
Special things to be careful off are:
Cut the beads on old tyres when removing them makes getting them off much easier and limits potential abuse to fitting the new tyres.
Get the fitter to reduce the air pressure on his wheel clamping on the tyre machine. The Lotus alloy is like cheese compared to modern rims and the standard clamping force on the 3 lugs that grip the wheel combined with the loads trying to lever the tyre off can break the rim at the clamps.
When levering the new tyre bead over the rim get the fitter to use something to spread the load on the rim, they have a standard plastic device they can use for this but they often dont bother. Any high point load from the lever can break the rim. Also use lots and lots of lubricant to help slip the bead over the rim.
Take it to someone who specialises in racing cars or old cars as they have more sympathy for these problems than the average quick fit tyre shop. Lower profile tyres ( 70% and 60% ) harder to fit than orginal 80% profile so need more care.
The best bet is to find a place like an alloy wheel refurbisher’s where they take great care replacing their clients’ tyres.
If you use a local place make sure they use a lot of lubrication, go slowly and choose the most experienced looking fitter (or at least steer clear of the spotty 16 year old whose hatred for his job is reflected in the reckless disregard he has for your wheels).
The Paul Matty reproduction Lotus alloys are a little different and don’t have this problem.