I just learned about this machine and thought I'd post some comments here to make sure the old-car guys are aware of it (I now see lots of posts under newer models on this forum). This machine includes a roller that presses against the tread to simulate the vehicle's weight during the balancing process. The purpose is to measure variations in sidewall stiffness which can produce an effect similar to an out of balance wheel at speed. The machine also measures variations in wheel roundness, and where there are both roundness and stiffness issues the tech can rotate the tire on the wheel to offset these effects. In the first 5000 miles on my Mark 2 project I've had the tires balanced twice on conventional machines at different shops, and neither was able to achieve a satisfactory balance. I just used a local shop with a Road Force machine and the difference is amazing - no noticeable vibration including at (ahem) highway speeds.

I had assumed the difficulty in balancing was due to the big wire wheels I'm running, but the tech said they were perfectly true and that the problem was with my sidewalls. These tires were purchased approximately 5 years ago earlier in the project and I was told this is old, especially for performance tires. Apparently the softer rubber compound stiffens with age, and the low sidewall aspect ratio aggravates the problem. The shop was able to get 4 of the 5 tires balanced within spec, and the 5th is now the spare. I was only charged $20 per wheel (I assume because none of the tires had to be dismounted), but I see where typical costs are in the $40 to $50 per wheel range. If you're having wheel/tire balancing issues definitely track down one of these machines. I've read where the competency of the tech is as important as the machine - the shop I used caters to Ferrari s and Porches, not that that's any guarantee.

 

Hunter Road Force balancers are fantastic & used with proper cones on wire wheels that clamp correctly on the outer hub as does a spinner always give great results with a minimum amount of lead weights. (inner cone clamps inside the wheel tapered bore & outer cone on the outer face of the wheel hub ~ never use a cone provided with many balancers that clamps on the inside of the outer wire wheel bore)

 

I always give the shop a copy of Dayton's balancing instructions. For their newer wheels at least it appears only the inner taper is critical (i.e., it looks like it's ok to clamp on the inside of the outer bore). Still, I'm thinking the specialty cones couldn't hurt and might indeed help, though I wonder how many shops here in the U.S. have them. Thanks for the info Glyn.

 

The inside of the outer bore is not accurately manufactured on most wire wheels. I follow MWS advice. Tried both ways & you always end up with more weights with an internal cone on the outer side of the rim & some wheels can't be balanced. This is true for billet turned centre hubs. Pressed centre hubs like old Dunlop wheels are even worse. Our Jags typically had Dunlop pressed hub wheels up until 1967 after which they switched to hubs turned from billet.

Experience tells me that this method is a disaster, Even Dayton says only applicable to their wheels made after 1990. They have probably improved machining accuracy on the inner bore but I've seen similar issues with Dayton wheels. For any original Dunlop wire & anything MWS makes it's a no-no unless you want trouble.




So should you do this & have trouble you know why.

The advice I give above is from Motor Wheel Service (MWS) UK.

https://www.mwsint.com/site/cms/cont...p?category=140

MWS Centre Lock balancing kit. Suitable for all common bore sizes.





This kit is expensive & designed for Tyre shops.
The Smoothride kit above is for the typical Jag owner to keep with his car when it comes to time for new tyres. XKs Unlimited sell in the US. Direct from Smoothride in the UK.

 

Ordered my Smoothride 52mm Kit kit today that a friend is bringing out to SA next week. We have proven Dayton to be quite WRONG time & time again in our Jag Club ~ even with their post 1990 production wheels. We will stick to the MWS advice which is correct & not carry a tonne of weight around on incorrectly balanced centre lock wheels. MWS has been around for a while & know what they are talking about. Dayton don't. BTW XKS Unlimited is now Moss USA.

Smoothride wire wheel balancing cones:

 

I have a set of the smooth ride cones which I take with me when ever I need tyres fitting to my wires. One of the problems I found though at the garage I normally use is that they have two balancing machines. I don't know the makes but the cones fit on one but not the other. The centre spindle on one of the machines is a wider diameter than the hole in the cone. Lucky for me they have two machines and the other one the cones fit on.

 

a number of popular nationwide tire sales/balancing shops around here have the machine but won't use it anything but NEW tires purchased at the facility. i suspect that in addition to forcing customers to purchase new tires from them, which may be the primary reason, they have had trouble using the machine successfully on less than perfect tires.

i had a recent experience with brand new tires that were giving me balancing problems. after a year or so of failing miserably to get them to stop vibrating at any speed above 60mph, i finally found a shop that had the machine in question and would use it on my wheels. after several hours of work, they informed me that the tires were not round enough for the machine to work properly. a new set of tires were purchased (elsewhere as it happened) and subsequently the machine WAS used and used successfully. whether or not it give superior results is something i cannot say as i have no direct comparison with which to make an assessment.

 

Yes Cass. Valid point. Smoothride trys to ameliorate the problem with 2 bushes provided. We know that Hunter machines have the correct spindle diameter. So look for them. They are probably the most popular balancer. I would say that 99% of our tyre shops use Hunter.

 

Huey ~ well equipped tyre shops should have grinders to grind the tyre round ~ Yes you loose a bit of mileage but they work well. The truth of the matter is that out of round tyres are simply unacceptable. You won't find an out of round Michelin. If you do it's a rim problem. Deflate the tyre & move it through 90 degrees on the rim & re-inflate. If that does not work throw the rim away or have it reset to round.

Motor Wheel Service (MWS) has been around since 1927. I think they know a thing or two about balancing Centre Lock Wheels.