6x10 JA Pearce Magna wheels with Spinners + arches?
Re: 6x10 JA Pearce Magna wheels with Spinners + arches?
The wheels have been on the car for over 10 years on the same wheel bearings and no issues.
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mab01uk
- 1275 Cooper S
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Re: 6x10 JA Pearce Magna wheels with Spinners + arches?
Keith Calver has an interesting 'Technical Info' article on his website about the effects of bigger wheel/tyre combinations. (Extract below and a link to the full article).
Wheels & tyres - Bigger wheel fitment consideration - Keith Calver.
"There are a number of things that need serious consideration no matter which wheel/tyre combination you decide to go for.
First and foremost is suspension and steering component condition. The original 10-inch combination is relatively 'forgiving' - masking slight component wear simply because it has relatively low leverage effects and dynamics as a whole. This encompasses everything affected by wheel/tyre weight and profile and the grip afforded by the tyre contact patch on the road. Wheel/tyre weight affects damper performance - their ability to keep the tyre in contact with the road surface the main issue. It also affects acceleration and deceleration generated by the 'flywheel effect' and steering by the 'gyroscope' effect. Tyre profile affects ride, comfort, handling and grip.
All these conspire to exaggerate any shortcomings in the suspension and steering components. Slightly worn swivel pins, top arm bearings, bottom arm and tie-rod bushes, track-rod ends, steering rack, and wheel bearings will become very worn in a very short space of time. Tired dampers will not be able to keep the wheel/tyre in contact with the road. This can be dangerous - it will adversely affect safety, as you are completely reliant on those four small tyre contact patches whatever you do in a car. If the tyre isn't in contact with the road surface, you can't steer, stop, or go. As outlined earlier - a situation made very much more difficult in a Mini (or any front-wheel drive car) as it's all going on at the same end at the same time. Lower profile tyres have less flexible tyre walls - affecting ride quality (making it bumpier), and less compliant (will follow all ripples, bumps and cracks in the road surface). Although it has to be said that a number of modern sports cars have huge wheel/tyre set-ups to not only increase grip - the larger over-all circumference 'bridges' some bumps/holes, thus 'smoothing' the ride out by reducing/eliminating some of the smaller bumps.
Wider tyres will usually increase grip that will apply greater leverage against all the suspension locating bushes and bearings. Any that are worn will cause the increased leverage to push and pull the suspension into unwanted positions/angles. The result is a wayward car that doesn't handle well - seemingly developing a mind of it's own at inopportune moments if not all the time. The more grip the tyre develops, the easier it is for it to overcome the braking capability of the set-up on your car - the extra leverage applied by the bigger over-all diameter worsening the situation.
Up-rated dampers are a must. The standard items are barely capable of dealing with the standard set-up when brand new (a nod in the direction of 'comfort' by the OE manufacturers) let alone when worn. Bigger wheels/tyres means more (un-sprung) weight to control when encountering road surface imperfections (bumps/pot-holes). The barest minimum should be 20% up-rated standard-type dampers. Personally I would only recommend starting at Kayaba 'Gas-A-Just' dampers (my current preferred type for cost/performance and fit), if not going to one of the adjustable sports types.
The message here then is to make sure your whole suspension is in first class condition before contemplating the change. This is an ideal opportunity to fit up-rated components if worn bushes need replacing. Up-rated bushes offer greater resilience in both wear and movement, which will help provide greater suspension location and control when a bigger wheel/tyre combination is fitted. Essential to maintain the good 'handling' aspects believed to be endowed by the Mini's original design. And make sure your braking system is capable of dealing with your wheel/tyre choice."
https://www.calverst.com/technical-info ... ideration/
Wheels & tyres - Bigger wheel fitment consideration - Keith Calver.
"There are a number of things that need serious consideration no matter which wheel/tyre combination you decide to go for.
First and foremost is suspension and steering component condition. The original 10-inch combination is relatively 'forgiving' - masking slight component wear simply because it has relatively low leverage effects and dynamics as a whole. This encompasses everything affected by wheel/tyre weight and profile and the grip afforded by the tyre contact patch on the road. Wheel/tyre weight affects damper performance - their ability to keep the tyre in contact with the road surface the main issue. It also affects acceleration and deceleration generated by the 'flywheel effect' and steering by the 'gyroscope' effect. Tyre profile affects ride, comfort, handling and grip.
All these conspire to exaggerate any shortcomings in the suspension and steering components. Slightly worn swivel pins, top arm bearings, bottom arm and tie-rod bushes, track-rod ends, steering rack, and wheel bearings will become very worn in a very short space of time. Tired dampers will not be able to keep the wheel/tyre in contact with the road. This can be dangerous - it will adversely affect safety, as you are completely reliant on those four small tyre contact patches whatever you do in a car. If the tyre isn't in contact with the road surface, you can't steer, stop, or go. As outlined earlier - a situation made very much more difficult in a Mini (or any front-wheel drive car) as it's all going on at the same end at the same time. Lower profile tyres have less flexible tyre walls - affecting ride quality (making it bumpier), and less compliant (will follow all ripples, bumps and cracks in the road surface). Although it has to be said that a number of modern sports cars have huge wheel/tyre set-ups to not only increase grip - the larger over-all circumference 'bridges' some bumps/holes, thus 'smoothing' the ride out by reducing/eliminating some of the smaller bumps.
Wider tyres will usually increase grip that will apply greater leverage against all the suspension locating bushes and bearings. Any that are worn will cause the increased leverage to push and pull the suspension into unwanted positions/angles. The result is a wayward car that doesn't handle well - seemingly developing a mind of it's own at inopportune moments if not all the time. The more grip the tyre develops, the easier it is for it to overcome the braking capability of the set-up on your car - the extra leverage applied by the bigger over-all diameter worsening the situation.
Up-rated dampers are a must. The standard items are barely capable of dealing with the standard set-up when brand new (a nod in the direction of 'comfort' by the OE manufacturers) let alone when worn. Bigger wheels/tyres means more (un-sprung) weight to control when encountering road surface imperfections (bumps/pot-holes). The barest minimum should be 20% up-rated standard-type dampers. Personally I would only recommend starting at Kayaba 'Gas-A-Just' dampers (my current preferred type for cost/performance and fit), if not going to one of the adjustable sports types.
The message here then is to make sure your whole suspension is in first class condition before contemplating the change. This is an ideal opportunity to fit up-rated components if worn bushes need replacing. Up-rated bushes offer greater resilience in both wear and movement, which will help provide greater suspension location and control when a bigger wheel/tyre combination is fitted. Essential to maintain the good 'handling' aspects believed to be endowed by the Mini's original design. And make sure your braking system is capable of dealing with your wheel/tyre choice."
https://www.calverst.com/technical-info ... ideration/
