Some customers who retreaded 17.5R25 regretted it because of hopping problems. How is it possible that a tire that had a first life suddenly begins to hop after retreading?

10 years ago, we had a few customers who experienced hopping. It’s even worse on graders has the equipment’s are now often automatically leveling then the hopping is amplified. To find a solution we interviewed a lot of our distributors and end users to realize that every retreader have the same issue once in a while. What was the solution or even the cause?

 

 

Following several observations, we started measuring tire balancing before and after retreading, and found that some 17.5R25s were up to 5 lbs unbalanced after retreading!

Pushing the investigation, we realized that the problem lay in the fact that some tires were kept in inventory, both by customers and by us, upright for a very long time, and a “flat spot” was formed. When the tire was buffed, it became round again, but extra rubber was left where the flat was. When the tire was inflated after mounting, the “flat spot” returned to its original shape, creating a bump… hence the hopping!

 

 

 

 

 

The Solution: All 17.5R25s are now laid on the ground for 24 hours before buffing, and they become perfectly round again. Also, to make sure this is systematic, our production system forces a 24-hour wait… no mistakes possible!

Result: No more hopping problem due to retreading on 17.5R25 at LanOTR since 2015.

 

 

 

The LanOTR team