Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) tires for Plus 8?

Could use some advice with respect to tires and rims on my 1990 Plus 8 that I acquired a few months ago. Have a front end vibration so took the car in to have wheels dynamically balanced. Shop examined car said there were two issues needed addressing first.

1) wheels (stock Morgan) are not hub-centric and I need spacers to fix and make hub centric . Anyone know what spacer size is needed and where to acquire them? I don't even know what they are called. Rim size below.

2) tires are seven yrs old and told they need replaced (not worn-just old) . I imagine this question will result in some diverse opinions but what is best replacement tire for normal road use (no track use)? Currently running Uniroyal Rain Tyre 205/60 R15 91v. Came with car. Spare (older) is Uniroyal Rally 340/60. Rims are Morgan 15x6.5. 307 inset. Code #8mks.

ALL help appreciated. Thanks. John.

John,

Firstly welcome to Talk Morgan, there will be lots of information and help here for you I am sure.

Regarding your problems, I can give you plenty of advice about tyres, as I too had to research this for my +8.
If you want a good all round road tyre then the Avon ZV-5 takes a lot of beating and comes with plenty of recommendations from users , Morgan dealers, and others. I use them in 205/60 x 15.
If you are not worried about ground clearance, or the very slight increase in fuel consumption, slightly inaccurate speedo etc then there is an even better (grippier) alternative , the Toyo Proxes T1-R, but this is only available in 205/55 x 15 which is smaller diameter, hence the points above.
Regarding the age of the tyres, the accepted wisdom here in UK is that old rubber should be replaced at around 5 years. Rubber hardens with age, and although there is plenty of tread left , there may not be a lot of grip. There are those (even on this forum ;-) ) who think this advice is just the tyre companies propaganda to make us replace them more frequently, but my experience is that I have a lot more wet grip since replacing my 9 year old Yokohama A520s with Avon ZV-5s

Regarding your first point I am really not sure what the "shop" are talking about. Do others here have any idea?
Do you have alloys or wire wheels? If the latter then I suspect that they are referring to the issues around getting the wire wheel "held" on their balancing machine. Many tyre fitting depots can now only balance wheels with stud or bolt fixing, they used to have a universal tool for using with wire wheels , but most now seem to have lost both the tool and the skill of using it. Let us know where you are located and someone might know a depot in your area who can manage the job successfully.
If you have alloys I really do not know what they mean, they should be able to balance an alloy wheel on standard equipment without the need for any spacers.

Thanks Andy. I really appreciate the input on your experience with the tires. Sounds like the Avons might be a good way to go. Yes, I think it is time to put some new shoes on the old girl. For safety, if no other reason.

I found a video on youtube showing the dynamic balancing while the tire is still on the car. https://www.youtube.com/watch?v=7Ugp-xWOnMQ

Still need to figure out the correct size spacers between hub and alloy rims.

Your wheels are the same as on my 1993 Plus 8: mine do not have any spacers between the wheel and the hub. Perhaps what your tyre shop is referring to is an adaptor to centralise the wheel on their machine? On the car, the cone on the wheel nuts sitting in the countersink of the stud holes does the job of centralising the wheel.
I guess from your spelling and vocabulary you live on the western side of the pond?

Here is my understanding: With dynamic balancing the tire and wheel are left on the car and not removed. Machine then spins the wheel and thus creates a more perfect balance. And if tire is not perfectly round it can be shaved. BUT to do this the wheel must be perfectly centered on the hub. Such a tire is called "hub centric." Hub centric are by far the best. My wheels are "lug centric" as they are aligned on the hub by tightening the lugs. To make them hub centric I need these spacers that fit the wheel tightly on the hub. Haven't been able to find any for the Morgan, although there are many for other cars.
Yes, located in Florida; guess you can tell.

Here is an example of hub centric rings.
https://www.motorsport-tech.com/4DCGI/h_yearmakemodel.html

Just can't find them for Morgan. Anyone know of a source?

John,
Your shop is correct, classic Morgan wheels are not hub-centric AND neither are the front or rear hubs. Assuming you get the wheels spun up in a lathe to machine a centralised hole and then then buy a hub centric spacer to reduce the internal diameter of the machined bore what exactly will that mate to? Nothing, because there is not a machined male lip for that purpose on either the front or rear hubs.
At the risk of sounding disrespectful, you may do better to find a different shop that doesn't want (to literally) re-invent the (Morgan) wheel.
Providing you have OEM wheel nuts and tighten them down in a 'star' pattern the wheel will centre correctly.

Horror: Thanks for the advice. Appreciate you being candid. I am beginning to believe the problem may be that the shop just does not "know Morgans", which is understandable as here in central Florida they are not common. Think I may just go with some new tires and a regular balance and see how all that works out.

May I say that I really appreciate the time that members take to respond to these "novice" questions. It really shortens the learning curve.
Thanks

John, they certainly don't know Morgans. Mine may have been the first they have seen, but I doubt that my wheels were collectively any better than yours. The guy that worked mine was named Mark.

FYI, I don't know how many wheels they believe to be bad, but I have one, off the car, that appears to be new. (have no idea where I got it.)

Cheers,

John,
Your existing tyres are 7 years old and not worn out, suggesting a low annual mileage. It is not unknown for tyres to develop a flat profile if they have rested in one place too long. If this is the case, they will dynamically balance but you will have perfectly balanced 'square' wheels that give an awful ride.
On my '72 +8; each of the holes through which the wheel studs go have a steel insert or sleeve. It is the bevelled part of the insert that the wheel nut centres and tightens against. If the wheel nuts are over torqued the mating surface can split or fracture. If this is the case, the wheel won't pull down evenly and you can get a wheel wobble.
Remove each wheel, inspect each mounting hole to determine that a bevelled mating surface exists. If all is visually OK, remount the wheel and re-tighten with a torque wrench (70-75 ft lbs), if the nut feels 'soft', i.e you are putting the right effort in but the nut still turns, then the insert may be cracked.
The inserts should be regarded as consumables. If the ends of the sleeves are missing or damaged the sleeve can be hammered out and new one inserted using a suitable sized socket as a drift.
If your tyre shop uses an air wrench / chatter gun to tighten the wheel nuts don't expect the inserts to last long.