Wheel balancing

[torque2me]

Hi Groupies.

I don't know what the Chinese calendar name is for this year but for me it is the year of the wheel (and tyre).

First, a Rover 75 (not the 1950's type). 3 Seasons wheel/tyre changed for winter types (what winter I hear you ask, but you know if they had not been changed we would have had a foot of snow and icy conditions). Next, about 20 GKN Kent wheels with different tyres in various sizes which besides being made donkey years ago had been stored (mostly incorrectly) for over 25 years. So, a much need sorting job to do. Decided not keep those with within legal tyre tread due to age concerns though only a couple had slight cracking in the tyre wall. Pretty good really! Then sorted the wheels into two groups; one for complete refurbishment (two to be scrapped) and about four for new rubber.

So, I've a set now that needs balancing. For Triumph suspension geometry it was advised (for ultimate results) to balance on-the-car. This was usually done on a Hofmann Finisher Balancer. NTC was about the only company with outlets in England. Since Halfords took over NCT yonks ago I doubt if they still have the equipment. I've looked on the Hofmann web site but cannot find any reference to on-car balance equipment. I'll e-mail at some point (and contact Halfords) but in the meantime does anyone know of a company providing on-car wheel balancing?

Kev

[johnnydog]

I'm just wondering where the advise to balance on the car came from...?
Are the wheel rims steel or the S alloy?
I have never had any Triumph wheel balanced on the car, and I have never had any issue with their balancing done off the car, apart from one S alloy which turned out to be deformed.
Many years ago, I had an issue with the balancing of one S alloy. This turned out to be the wheel itself rather than bad workmanship.
Most alloy wheels rely on being centralised on the balancing machine with the wheel centre being removed and the cone shaped wedge being tightened against the alloy centre which also centralises the alloy on the hub of the vehicle.
The S alloy centre is only decorative and the 'snout' plays no part in centralising the rim on the hub of the car - this being done only by the four studs combined with the shoulder or shank of the wheel nuts (this is one major reason why the correct wheel nut should be fitted to S alloys as they aren't tapered between the head of the nut and the thread, which on its own would normally centralise the wheel.on the hub).
Assuming you are talking about S alloys, the outer part of the snout where the circular disc fits is not actually the exact centre of the wheel being purely decorative, so I understand the correct way to balance them is using a specialised 4 legged clamp that centrally locates the rim on the balancing machine using the holes for the hub studs which are perfectly central and true to the rim.
I would also presume, still talking about S alloys, the more recent 'aftermarket' ones now supplied by some of the bigger Triumph specialists are made to a greater degree of accuracy than the originals in the 1970's!
Assuming all your suspension components are in good order, and the rims are true, then I see no reason why the standard balancing off the car should give perfect results?

[torque2me]

I'm just wondering where the advise to balance on the car came from...?

From many in the trade be it BL or independent especially the staff at the RAC facility at Maypole, Birmingham (two former Triumph final inspection bods). Your mileage/experience will be different

Are the wheel rims steel or the S alloy?

As stated GKN Kent alloy wheels as fitted to the 2500s and Stag.

I have never had any Triumph wheel balanced on the car, and I have. I've
never had any issue with their balancing done off the car, apart from one S alloy which turned out to be deformed.
Many years ago, I had an issue with the balancing of one S alloy. This turned out to be the wheel itself rather than bad workmanship.
Most alloy wheels rely on being centralised on the balancing machine with the wheel centre being removed and the cone shaped wedge being tightened against the alloy centre which also centralises the alloy on the hub of the vehicle.
The S alloy centre is only decorative and the 'snout' plays no part in centralising the rim on the hub of the car - this being done only by the four studs combined with the shoulder or shank of the wheel nuts (this is one major reason why the correct wheel nut should be fitted to S alloys as they aren't tapered between the head of the nut and the thread, which on its own would normally centralise the wheel. on the hub).

You have answered the question of why balance the wheel on the car. The normal set-up with off vehicle balancing is that the wheel is balanced for the balancing machine. Thus when it it is put on the vehicle it has not been balanced for that suspension set-up but is probably within o.k. parameters. I've done shed loads of wheels of vehicle but that is only due to the fact on-car balancing seems to have been eliminated from the trade. A Hofmann will balance much more accurately to the fact the one needs to mark the stud/stud hole if the wheel is removed to enable the wheel to settle to the balance pivots for that suspension which has wear at various points. A off vehicle balancing machine is incapable of doing that.

Assuming you are talking about S alloys, the outer part of the snout where the circular disc fits is not actually the exact centre of the wheel being purely decorative, so I understand the correct way to balance them is using a specialised 4 legged clamp that centrally locates the rim on the balancing machine using the holes for the hub studs which are perfectly central and true to the rim.
I would also presume, still talking about S alloys, the more recent 'aftermarket' ones now supplied by some of the bigger Triumph specialists are made to a greater degree of accuracy than the originals in the 1970's!

The 4 legged clamp might be a work-around/update/simpler system to the Hofmann and thus that is likely to be my avenue of interrogation of tyre fitting establishments.
Do you know of any companies or establishments that have this equipment as I've only seen the cone centralising being used.

Assuming all your suspension components are in good order, and the rims are true, then I see no reason why the standard balancing off the car should give perfect results?

As I've tried to explain the Hofmann takes into account some of the wear in suspension components (probably not excessive wear). Who has a non wearing suspension system?
Off car balancing will not provide "perfect" results but probably "acceptable" outcome. A Michelin XAS/XVS would do 30,000 miles and that would mean some suspension wear.

We are going to have to have different views on this subject. As far as I can judge, since the early eighties we have had to accept a less precise balancing system but that is just my view and I don't mind if others do not subscribe to it.

Kev

[johnnydog]

It seems I may have (unintentionally!) ruffled some feathers....
Whilst I appreciate your views and understand your comments, I do not think there are many of our Triumphs out there that are so finicky that the wheels require to be balanced off the car as opposed to on it.
If the wheels on your Triumph can't be satisfactorily balanced off the car, then surely that suggests a separate issue rather than wheel balancing?
There are a lot of other factors that can cause issues with balancing or what is perceived as poor balancing -
Inexperienced tyre fitters?
Tyres incorrecty fitted to the rim with regards to the weight / heavy spots of the tyre (indicated markings on the sidewall)?
Hub / brake disc run out?
As discussed - suspension /steering component wear?

Most new cars during manufacture are fitted with wheels that are balanced off the car.

I regularly drive performance cars that are capable of speeds towards 200 mph, which tend to eat tyres and replacements are fitted by the prestige car dealership and are balanced off the car. I have never experienced balancing issues with them (not that I drive over 70mph - ever! )
I personally own a 10 year old car that is top speed limited to 174mph, and is on its 3rd set of tyres; the latter two sets balanced off the car, with no subsequent issues. Suspension components have been changed due to wear, which have not had an adverse affect on wheel balancing.

I don't really think our Triumphs fall in that category and although it's against your thoughts on the subject, if any wheel balancing imbalance is that noticeable, surely there must be another cause?

Have you considered 'forced wheel balancing'? This takes into account heavy / light weight areas of the tyre and rim indicating the optimum position of the tyre relative to the rim for perfect balancing.

The last time I saw an attachment that locates a rim on the wheel balancer by the stud holes was at my local ATS - I'm sure any reasonable tyre fitting company should possess one.

I would have thought that modern wheel balancing machines today are far more advanced compared to those of yesterday, but again the experience of the fitter plays a big part in it.

We may have to agree to disagree in our opinions on this subject!

[Alec]

Hello Torque2me,

I haven't seen an on car balancer for decades. While theoretically they are superior the mass and accuracy of the hub and disc means the effect is small compared to the wheel and tyre.
I was not aware, never having an 'S' that the wheels needed adaptors for standard balancing machines, something shared by wire wheels incidentally. (Most tyre places don't have the correct adaptors for them)
That said I have always had my wheels balanced off the car with satisfactory results.

Alec

[torque2me]

Hello Torque2me,

I haven't seen an on car balancer for decades. While theoretically they are superior the mass and accuracy of the hub and disc means the effect is small compared to the wheel and tyre.
I was not aware, never having an 'S' that the wheels needed adaptors for standard balancing machines, something shared by wire wheels incidentally. (Most tyre places don't have the correct adaptors for them)
That said I have always had my wheels balanced off the car with satisfactory results.

Alec

Thanks for the reply Alec. You confirmed my memory cell that it was ATS that had the equipment but I'm guessing when Halfords took them over that all went.

Didn't want to get into a pros and cons regarding balancing with johnyydog but he did provide the info that GKN Kent wheels have trouble locating centrally on some(?) machines. That is my experience and hence my query as to whether any company still had a Hofmann Finisher Balancer about. I guess I'm going to have to look into what other fixings are able to be attached to balance machines for better central location

Cheers, Kev

[johnnydog]

I don't think Halfords have ever owned / been a part of or have ever 'taken over' ATS - aren't ATS (ATS Euromaster to give them their full title) owned by Michelin?