In this article, we’ll discuss where the rubber meets the road, literally: tires and wheels. Tires are the most commonly replaced consumable on a motorcycle, so if the tires on your potential purchase need to be replaced it’s not a deal-breaker, but something that could help you negotiate a lower price. The first part of inspecting the tires is checking for damage. While someone else rolls the bike forward, inspect the tire’s tread looking for any cuts or sharp objects (nails, screws, staples, etc.) that can puncture the tire. Next, check the production date, which is usually found inside an oval on one or both sidewalls of the tire. The date format of this isn’t the normal Month Day Year. It’s done numerically, with two digits for the week and two for the year, eg. 1718, which indicates the tire was made on the 17th week of 2018. The general rule of thumb is a new tire off the shelf is only good for 5 years from the date of purchase. After that it may not perform as designed, and replacing it is recommended.
If the tire is fresh enough, the next thing to check is wear. You can quickly check this by looking for the tire’s wear bars. These are small bumps in the cutouts of the tire’s tread that indicate when the tire is too worn and should be replaced. If the tread of the tire is level with the wear bar bumps, the tire is worn out. Another quick test is to take a US penny and place it upside down inside the tread groove. If you can see the top of Honest Abe’s head you have a worn tire (approximately 2mm of tread remain). Since motorcycle tires are curved and may not wear evenly, check for excessive wear in the center and both shoulders of the tread.
Along with wear there are other indicators a tire may be at the end of its life. Tires heat up when being used and cool off when at standstill, so they can crack as they age. The most likely place to find cracks are in the tread grooves and the sidewalls. Sidewall cracks can also indicate current or previous low tire pressure. If you’re looking at a motorcycle with knobby tires you should also look at the base of the knobs to see if they are tearing off. Keep an eye out for cuts and missing chunks, as well.
After verifying the tires are good, the next item to inspect are the wheels, specifically the rims. Check for dents or cracks in the rim bead (the outer edge of the rim). Serious damage to the rim bead can prevent the tire bead from sealing properly, causing an air leak. If you find any damage that is suspect, put some soapy water or spit (if it’s ok with the owner) on the damage and see if bubbles form. If so then the wheel is leaking air. If not, you’re not yet in the clear. The tire bead may have bent with the rim, preserving its seal, but a new undamaged tire might not seal correctly on the rim, rendering the wheel unuseable. Leaking or not, a big dent in the rim is worth having a professional look at and verify its safety. Additionally, check for deep scratches and gouges in the rim. While it may not pose an operational issue it may indicate a crash or poor form installing tires.
For wire spoked wheels make sure the spokes are in good working order. Check for bent, heavily rusted, or loose spokes. Bent or loose spokes can also indicate a bent rim. Heavy rust or corrosion is a bit subjective but a good rule is if you scratch it and it comes off in chunks and leaves pits in the metal it’s more than simple surface rust. To check for loose spokes simply give each spoke a shake. If it moves, it’s loose, and the wheel will need to be trued and possibly balanced.
The last thing to check is a difficult one to do in a parking lot: wheel bearings. You may not be able to accurately check them before you buy the bike, but it’s something you or your mechanic should check after purchase. Wheels bearings allow the wheel to spin freely, and it takes an experienced mechanic to know the difference between normal operating noise, and a bad bearing. If it turns out they are bad, don’t worry, you didn’t buy a lemon. In most cases they are a cheap and relatively easy thing to replace.
If you find any or all (yikes!) of these issues it doesn’t mean the bike is junk. These tips are just here to educate and help you negotiate a fair price for the bike you’re looking at. If the wheels and tires pass muster, you’re not quite out of the woods yet. There’s still chassis, power train, suspension, bodywork and more to inspect before making your purchase. We’ll cover those in a future post – stay tuned.
In the meantime, check out some of the latest used bikes on Cycle Trader.