After struggling constantly for at least 8 years to keep at least one of the front tires on my Cub Cadet ZRT 50, I finally decided to try a set of solid core tires. After much research I decided to try them. The price was great. They came with plenty of spacers and washers to get a snug fit. I've seen several reviews of poor quality grease fittings. I hesitated a bit but decided to try them. There were no problems with zirconium fittings. Nice and tight, the knots are lubricated with no problems. The ride can be a little stiffer than the originals, but not as bad. I have mowed about 2 acres and my yard is quite bumpy and by no means flat. I've been using it for a few months and couldn't be happier.