New XK 120 owner here. Placed new Goodrich 600-16 bias ply tires from Coker. Driving around town mostly. But this weekend braved a 100 mile r/t journey to a car meet at a beautiful Oregon vineyard. A 6 mile portion of that trek required use of a 65 mph highway. At about 58 mph I felt a vibration seemingly coming from the tires… the kind of vibration that warns one not to go any faster. Felt like it was coming from the rear end…and a vertical vibration (if that makes any sense). Smooth below 58 mph. Will check tire pressures tomorrow. Original wire wheels - spokes are sound. Spinners secure. Any ideas? Thanks in advance.
Tires balanced? Wheels trued? Those are the most common causes of vibration at higher speed.
Re Check balance first (did Coker install the new tires doubt it since yo did not buy new wheels from them.).so…balancing a tire on a wire wheel is not easy and needs special equipment and care…I suspect balance. You can find a thread on this recently, or on MWS wire wheel site. Find a shop that can really do wire wheels…but only counts if they can do a knock off. A bolt on wire wheel is like any other…talk to shop manager…be sure…a few ways and tips…one, a tire can be balance checked, the wheel checked and the tire mounted so it is best positioned to match the wheel. The special cones for wire wheel centering are needed for spin and static balance. I used to have rally/race tires “shaved” for true round before balancing. Modern tires should have closer tolerance. If chrome wires, be sure they have “touchless” if tire needs to come off and on. Balance first, but also wiggle drive shaft…a failing U joint can vibrate and feel like rear tires. By the way, always have car wheels up…when loosen or tighten the spinners. Light grease or anti-seize on threads whenever opportunity to do it. Do not overtighten, it just damages the threads, tite and 2 whacks, done. These are new…so prob not a tread to carcass separation…but check anyway…sometimes can happen even if new if the “glues” are faulty in a spot, but more common on old dried out tires. So…check balance, check drive shaft U joints…test drive again. Nick
60mph - vibration = wheel balance 99.99% of the time
I did notice today that the two left side wheels (painted not chrome) had lead balancing weights present, and right side wheels had none…seems kind of fishy. Les Schwarb Tires whom mounted the tires to the wire wheels likely didn’t have the proper equipment (as you mentioned) to balance correctly and I didn’t inquire as to any balancing they may have done, or not done when I had the job accomplished. And they refused to take off/put on the wheels to the car…claiming liability issues. So I will investigate the balance situation and check the u-joint. Appreciate your insight. Thanks Nick.
Check out smoothridecones.com from the uk, they manufacture cones to fit the 52 mm hub of jag wheels. A set costs 75 pounds sterling, shipping extra.
I ordered a set and should get then this week,
I had a similar problem when I replaced the tires and tubes on my original XKE 1966 wire wheels.
Everything was balanced at the shop but after 10 miles the vibration appeared.
I took it back and discovered that a few of the stick-on balancing weights had fallen of one wheel of because they would not adhere due the the wax job.
We went through the balancing one more time and discovered that all the wheels were out of balance. The technician could not understand. This time the wheels stayed balanced. My only guess is that the tires need to be pumped up and allowed to round out before balancing (Something that was not originally done). Some of the spokes may have been a bit loose.
Do the “tuning” trick of tapping the spokes to hear if they all sound the same.
Live and learn.
Thanks Bob. I had the wheels balanced while on the car…seemed to have helped as ride is smoother at slower speeds and will test at 65 mph+ next weekend. I can’t imagine these cars rolling along at 120 mph + however.