Motorcycle Tyre (Tire) Puncture Repair Advice
Motorcycle Tyre (Tire) Punctures
Puncture repair advice What punctures are safe to repair? When to repair, when to replace? Safe to repair?
I always carry a puncture repair kit on me. You can see a review of the best motorcycle puncture repair kits here.
Motorcycle Tyre (Tire) Puncture Repair Advice
Sods law isn’t it that invariably when you get a puncture it’s in a tyre that’s done no more than a few hundred miles! 🙁 Why is it that new / nearly new motorcycle tyres appear more prone to punctures?! (in my experience anyway – if anyone knows why, please tell me!)
The questions:can punctured motorcycle tyres be repaired? ~ when can a motorcycle tyre puncture be repaired? ~ is it safe to repair a puncture in a motorcycle tyre? ~ what motorcycle tyre punctures can be repaired?
Quick and simple advice – only ever use DIY tyre repair kits as a temporary ‘get you home’ fix, always take punctured motorcycle tyres to a reputable authorised motorcycle tyre dealer for advice and a professional repair if appropriate.
Why’s my tyre flat (finding slow punctures)?!
If you frequently have top up the air pressure in a tyre chances are that you have a ‘slow puncture’, bad seal between the tyre bead and wheel rim, a badly seated tyre valve or a leaking tyre valve. It’s easy to find the source of the problem…
First look for any signs of a foreign object embedded in the tyre. If you can’t find anything find an old spray bottle, mix a little washing-up liquid (liquid soap) and water solution then just spray the tyre down. Look for bubbles that will form where any air is escaping, make sure you spray the valve stem and around its base. Another method that’s even more effective is to take the wheel off and submerge it in water…. :-0
Don’t lie the wheel flat in the bath (or whatever receptacle), you don’t want water in the wheel bearings 😉
Is it safe to repair a tyre that’s been run flat?
It is dangerous to re-inflate a tyre which has been run flat or seriously under-inflated and such tyres should be removed for thorough examination by a tyre specialist.
Repairs to motorcycle tyres and tubes should be carried out by a tyre specialist and in accordance with the current British Standard AU 159 or tyre manufacturer’s recommendations. On no account should a tube be considered as a puncture repair remedy. Permanent repairs can only be carried out following removal of the tyre from the wheel to allow a thorough inspection internally as well as externally to ensure there is no hidden damage which could result in failure. In order to avoid such a hazard, neither externally applied plug type repairs nor liquid sealants are recommended and tyre manufacturers cannot be responsible for problems
resulting from their use. (extract from “Motorcycle Tyres and Your Safety” leaflet by TyreSafe.org – download the full leaflet here)
British Standards for puncture repairs
A British standard exists for motorcycle tyre repairs (BSAU159f), which determines the strength of the repair and where it can and can’t be made in the tyre.
BSAU159f states that no repairs are allowed in the sidewalls (these flex continuously and a repair is likely to fail), and the standard says repairs are not allowed on high speed Z-rated tyres.
It says a tyre must be inspected by an expert for secondary damage (a nail which punctures the tread might also damage the sidewall inside), run-flat damage (determined by a darkened or marbled appearance inside the sidewall), exposed cords and so on.
Michelin, however, is the only manufacturer that recommends that its Z rated tyres can be repaired in accordance with the previous BSAU159e. (see below)
Repairs can only be made in the center of the tread area, to within 25% of each side of the center line.
Only two repairs per tyre are allowed up to the J (62mph) speed rating, and one up to the V (over 130mph with 155mph maximum) speed rating. Up to the J rating, repairs no bigger than 6mm are allowed, and up to the V rating only up to 3mm is allowed.
All repairs must be carried out with a mushroom-type plug, which fits into the puncture hole from the inside and bonds with the tyre by vulcanisation.
Anything else and the BS says the tyre must be chucked. If your tyre repairer says the same and quotes similar reasons, he’s being honest.
In accordance with British Standards (BSAU 159) only certain areas of the tyre can be repaired. This is demonstrated below by red areas in the diagrams below.
The repairable area is defined as a percentage of the tyre’s nominal section width and this is dependant on the type and size of the tyre, for motorcycles:
|Area T is defined as 50% of Nominal Section width|
|Injury Limitations: Straight Penetration Damage|
|Tyre||Max. Size of Damage||Max. no. of repairs|
|Up to J Speed Rating||6mm||2|
|Above J up to V Speed Rating||3mm||1|
|Above V Speed Rating||–||0|
There are substances on the market that you put into your tyres and supposedly just forget about punctures altogether (‘UltraSeal’ ‘PunctureSafe’ etc). Some of these products are good (apparently), some are not. The best thing to do is get expert advice before adding anything that can effect your tyres in any way at all. See below re use of tyre sealants!
AndyW – I know two guys that had used a tyre prevention sealant, the sort you run in your tyres all the time (and have read of other peoples similar experiences!) that had punctures and the stuff didn’t work, I know, I was there! On both occasions on taking their wheels to a tyre dealer for puncture repair the repair job was made a lot more difficult due to the clean up job required to get rid of the sealant before a tyre plug repair could be done.
On another occasion a friend tried the repair and reinflate type sealant on getting a puncture…….we wheeled the bike to a nearby petrol station, bought the stuff, sprayed into the tyre via the valve as per instructions and inflated the tyre to the recommended pressure. On riding off the tyre was deflating again immediately with the horrible gooey (supposed) tyre sealant squirting from the puncture hole all over the back of the bike. Again, tyre technician not impressed when the tyre was taken in for repair.
😉 Carry a roadside puncture repair kit, the sort that you push rubber mushroom like plugs or the ‘sticky string’ type seals into the puncture.
Is it safe to use a tyre sealant?
(advice from TyreSafe: http://www.tyresafe.org)
TyreSafe does not recommend pre-puncture sealants as there is an inherent risk of the primary damage extending in service and/or of internal secondary damage. The continued use of this tyre in such a condition may lead to serious tyre failure. Post-puncture sealants are regarded purely as a “get you home” measure and introduced following a puncture. The manufacturers recommendations detailed on the can should be strictly followed.
Motorcycle Tyre Puncture Repair – What Michelin Advises
Click image to view the PDF document:
Motorcycle Tubeless Tire Repair Information from Dunlop
Dunlop recommends only permanent repairs performed from the inside of the tire, using a combination patch/plug method. Never attempt a repair from the outside, or inject a sealant, or simply use an innertube, a patch or a plug as a substitute for a proper repair.
Only a qualified tire repair shop or motorcycle tire dealer should perform repairs. Inspection of the tire and adequacy of repair becomes the responsibility of the person actually performing the repair and Dunlop does not warrant the results of a repair in any way. Combination patch/plug repair kits for use by the repair shop or dealer are available with accompanying instructions from companies such as:
200 Paris Ave.
Northvale, NJ 07647
Technical Rubber Co.
P.O. Box 486
Johnstown, OH 43031
Tip-Top/Moto Combi Kit
Tech Uni-Seal® Repair Kit (Also has been marketed by Honda, Kawasaki, and Yamaha with their own part numbers.)
NOTE: There may be suitable repair kits and materials provided by manufacturers other than those listed above.
Before any repair should be attempted, however, a tire must be removed from the wheel and thoroughly inspected. The following are minimum guidelines for the repairer:
Tires should not be repaired if any of the following conditions exist:
A tire has been previously injected with a sealant/balancer.
The puncture is larger than 6mm (1/4″) in diameter.
The puncture is not perpendicular to the carcass.
The puncture is in the tire sidewall.
Separation of plies, tread separation, separation of any other components.
Cut or broken ply cords.
Broken or damaged bead wires.
Cut or damaged chafers (bead area).
Deterioration of the carcass inside the tire due to “run flat” or underinflation.
Cracks or other damage to the integrity of the inner liner.
Excessive wear – tire should have at least 1/32 of an inch of tread depth, excluding tread wear indicators.
Cracks in sidewall or tread.
Impact breaks, cuts, snags or gouges that penetrate the surface.
There should be no more than one repair in any quarter of the tire and no more than two repairs per tire.
The wheel itself must be in good condition. Any cracked or bent wheel, however slightly, may allow the loss of air and cause subsequent deflation of the tire.
Following repair, the valve assembly should be replaced and the tire/wheel rebalanced.
Speed should not exceed 50 mph for the first 24 hours after tire repair and the repaired tire should never be used at speeds over 80 mph. The repairer is solely responsible for instructing the motorcyclist as to the restrictions to be placed on tire use following repair.
In summary, NO form of temporary repair should be attempted. Motorcycle tire repairs leave no room for error and any doubt as to inspection or adequacy of repair should be resolved by discarding the tire.
Be sure to consult our Motorcycle Tire Limited Warranty, Care and Maintenance brochure for additional information regarding the use of Dunlop tires. Seek a qualified motorcycle tire repair center for more details. NEVER ATTEMPT TO REPAIR A DAMAGED TIRE WITHOUT THE AIDE OF AN EXPERIENCED TIRE MECHANIC.
See also: BMW R1200GS Tyre (Tire) Puncture Repair