I use to use BP Ultimate but am currently using Shell Diesel Extra with Millers Diesel Power Plus Sport 4 (normal dosage). Tyres are Goodyear Excellence 205 55V 16 all round with pressures at 31 psi, driving conditions variable but mostly a mixture of urban with the majority of miles on A and B roads with max speed around 55 to 60, dual-carriageways/motorways 60 to 70 mph.
Techniques include changing to a higher gear asap, decelerate well before roundabouts, junctions, lights, hazards etc. and only use brakes if required. Always try to keep some momentum of car after braking to reduce acceleration fuel losses. When driving downhill no throttle is used at all when the car is going over 50 mph, no coasting either. For uphill feed in enough power just before the incline to utilise max torque characteristics of the engine. I "feel-in/out" the throttle to engage the max potential from the car and use multisensing techniques for environmental conditions and vehicle feedback.
I'm getting around 64 mpg overall during summer conditions which dropped to a worst overall of 56 mpg brim to brim during the winter. Long distant journeys of mostly motorways and duals I get 64 mpg. On long journeys of A and B roads I get over 70 mpg using brim to brim to measure.
Edited by MikeTorque on 14/07/2008 at 01:42
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Just back from Kwik-Fit - turns out there's not much left on the rears, either.
So that will be four Pirellis, sir, fitted, tracked and balanced with new valves for £267.
Works out at £67 a corner, which could be worse.
Bit surprised all four of the old Avons have worn at pretty much the same rate, I'm sure the original equipment rears lasted longer than the fronts.
Edited by ifithelps on 17/07/2008 at 11:04
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I have a Focus 2, 1.6 tdci that at 28k is soon to be needing tyres.
I'm suprised that the rears are only slightly less worn than the fronts.
I wonder if this is due to good front / rear handling balance, the firm zetec suspension etc., since you would expect the rears to last much longer.
I don't think it can be due to the brakes. The rears including the handbrake are lousey!
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I do hope the quality of your Goodyears are better than mine, tyres that needed this amount of balancing would'nt have left a Michelin site. All four are the same, replacing previous Goodyears, replacing previous OE Dunlops neither of which needed anywhere near those amount of weights. No vibration at any speed so the weights are doing there job of rectifying a poorly balanced tyre from the factory.
tinyurl.com/6nvsqw
tinyurl.com/6gc42a
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Mustangman,
You're right about the brakes, they let down what is an otherwise very good car.
I'm also going to agree with you about the all round tyre wear, and put it down to the Zetec's finely tuned suspension.
I like the car, so I'm prepared to be charitable.
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The front tyres of a Focus 1 generally wear faster than the rears, unless the car has been used to carry regular rear seat loads or boot loads in which case the rears will wear quicker than expected.
Do Pirelli's cause road noise issues on the Focus 1 ?
No problem with the Goodyears Excellence fitted to my car, the tyres came perfectly balanced.
It could be that if excessive wheel balancing weights are required then the wheel (metal) itself isn't balanced rather than the tyre itself being unbalanced.
Edited by MikeTorque on 18/07/2008 at 00:15
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Good to hear this report on the "Excellence" Mike. It's a tyre I've been looking at for both the Vectra and the Galaxy we run.
Regarding the post on equal wear on the Avons, I've heard on another board that Avon use a softer compound, for grip, hence the wear rate. There is always a trade off between longevity and grip on tyres.
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It could be that if excessive wheel balancing weights are required then the wheel (metal) itself isn't balanced rather than the tyre itself being unbalanced.
The goodyears replaced the previous goodyears, that replaced the previous OE Dunlops, neither of which needed the excessive amout of weights that the new covers have. The wheel tyre combo are balanced at all speeds, all 4 wheels needed similar amounts of weights to balance them.
Quality wise they appear very poorly balanced, I've seen remoulds with less weights.
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>>The wheel tyre combo are balanced at all speeds
Not possible. Dynamic balancing is a compromise, owing to moments of inertia.
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It could be that if excessive wheel balancing weights are required then the wheel (metal) itself isn't balanced .......
Because of the method of manufacture, it's inevitable that steel wheels are inherently less in balance (and less circular, and have more axial and radial runout) than alloy wheels. This is why I prefer alloys.
Edited by L'escargot on 18/07/2008 at 12:38
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Mapmaker, I don't own a balancing machine, but have driven the car at various speeds up to around 90MPH and I could take my hands off the wheel at any speed between 5 and 90MPH, therefore the weights added to balance the goodyears must be correct?
I'm equally balanced too, I've a chip on both shoulders ;o)
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Mapmaker I don't own a balancing machine but have driven the car at various speeds up to around 90MPH and I could take my hands off the wheel at any speed between 5 and 90MPH therefore the weights added to balance the goodyears must be correct?
It may be viewed as a pedantic point... but a wheel can only ever be dynamically balanced at one speed. Google moments of inertia.
It can only ever be a strictly correctly balanced wheel at one speed. So if it's balanced at 70, it's excellent between 60 and 80, and acceptable between 40 and 100. Below 40 it doesn't matter as the car is not going quickly enough. That sort of thing.
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It makes perfect sense to me mapmaker, thank you ;o)
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Mapmaker,
Balance, for axially short items such as wheels has nothing at all to do with speed. A balanced wheel is a balanced wheel at any speed.
There's no compromise to do with moments of inertia involved at all.
If you're dealing with a very long shaft, like a power station turbine shaft, then, yes, owing to shaft flex, it does become much more complex, but, for wheels and tyres, no.
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Some stuff I wrote for a recent thread in the technical forum
>>I wonder at what roadspeed the wheels are balanced at.
It doesn't matter. Seriously!
What does matter is the difference between the signal from the machine's sensors, and the amount of spurious noise measured by the sensors. So, hand spun wheel balancers can, and do, give excellent results, because there's no vibration from the motor and transmission interfering with the signal.
The other thing is that imbalance is not speed dependnet at all! By that, I mean that the imbalance itself is caused by an uneven distribution of mass, there's nothing to do with speed there.
What is speed dependent is;
a) The amount of force (or moment for dynamic imbalance) produced by a rotating wheel is proportional to speed squared.
b) In the vehicle, you tend to only feel the imbalance when it excites a resonance of either the suspension, or steering.
Point a) means that spinning the wheel faster will give more output from the machine's sensors, but, in general, the sources of vibration and noise in a machine will also increase in the same way - you don't, necesarily, gain by balancing with a quickly spinning wheel.
So, a wheel that is truly and properly balanced at whatever speed on a machine can be run at varying speed on a car, and be OK.
A wheel that is not properly balanced will have some speeds - on the car - where the imbalance is felt by the occupants.
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Years ago, we used to balance wheels on the car - one corner jacked up.
I think wheels are now balanced on a machine off the car.
Is one method better than the other?
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>>Is one method better than the other?
Yes..., and no!
Yes in that on-car balancing can pick up imbalance of the hub and driveshafts if any is present. (It's quite unusual for any to be present, but it does happen)
No, in that on car balancing typically uses one pickup mounted on a device that looks a bit like an axle stand. With one sensor, it's impossible to get the two position indications you need for an inner rim weight and an outer rim weight to provide dynamic balance.
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The front tyres of a Focus 1 generally wear faster than the rears ........
Don't the front tyres of most, if not all, FWD cars wear faster than the rears?
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Just for info, I've just had all four of my 205 / 45 / 17 tyres changed on my Focus to Falken 452's at 28k miles.
Got the deal for £ 302, all in, via an internet company with a bit of "secret code" discount.
First impressions are very good, improved steering feel and good wet road braking. ( useful at the moment!) we'll have to see how long they will last.
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