Author Topic: tyre pressures  (Read 6567 times)

alex1234

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tyre pressures
« on: September 17, 2008, 10:26:15 AM »
hi all ,can anybody tell me correct tyre pressure for 175/70R13 tyres ,
thanks
alex..

istreatf

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Re: tyre pressures
« Reply #1 on: September 17, 2008, 11:21:39 AM »
I would start at 20 psi F&R then go down from that, depending on whether you want handling or comfort. I run around 15/16 psi all round so my kidneys stay intact and have a nice comfy ride. Anything more than 20 and you might have renal or spinal failure. Balance on most Bulldogs is as near 50/50 F/R as dammit I am informed, so no need to have different tyre pressures front and rear. If you do the calculations as far as tyre contact to road/weight of the car you will find that somewhere between 15 and 20 PSI is correct.
Ian Streatfield, SE London and N Kent Area Rep.
Lunchtime meetings on 2nd Tuesday of the month at the Crown, Shoreham High Street, Kent from 12:30 onwards.

alex1234

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Re: tyre pressures
« Reply #2 on: September 17, 2008, 01:50:41 PM »
thanks,istreatf. Good god ! I have been putting in 30 psi !
Did seem a bit bumpy ---- ouch ....!!!
alex.

istreatf

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Re: tyre pressures
« Reply #3 on: September 17, 2008, 03:28:18 PM »
Don't worry - everybody does that at first as they do not appreciate that a Bulldog only weighs 600 or 650 kgs, which is only around three quarters of the weight, if not a lot less, than a clone box. It's right though!
Ian
« Last Edit: September 17, 2008, 07:48:18 PM by istreatf »
Ian Streatfield, SE London and N Kent Area Rep.
Lunchtime meetings on 2nd Tuesday of the month at the Crown, Shoreham High Street, Kent from 12:30 onwards.

bertiewhite

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Re: tyre pressures
« Reply #4 on: September 18, 2008, 08:57:21 AM »
thanks,istreatf. Good god ! I have been putting in 30 psi !
Did seem a bit bumpy ---- ouch ....!!!
alex.
You're not alone Alex, I did the same as well. Still waiting for my wires to come back form the refurbishers - looks like I've missed the summer now :'(

istreatf

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Re: tyre pressures
« Reply #5 on: September 18, 2008, 07:21:00 PM »
Somehow don't think you have missed the summer, we have not had it yet.
Ian Streatfield, SE London and N Kent Area Rep.
Lunchtime meetings on 2nd Tuesday of the month at the Crown, Shoreham High Street, Kent from 12:30 onwards.

Tim Hooper

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Re: tyre pressures
« Reply #6 on: September 20, 2008, 11:09:31 AM »
I think it was Mr Dee who once told me that the best way to find the correct tyre pressures for a given car was to examine the wear across the tyre's tread.  When it wears evenly across the width of the tread then the pressure should be somewhere near right.

The only caveat to this is that if you lower the pressures to a ridiculous degree, then the tyre may not stay sealed onto the rim!

My old 'dog was perfect at 16psi all round.

tim

istreatf

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Re: tyre pressures
« Reply #7 on: September 20, 2008, 11:17:35 AM »
That is an excellent way Tim, however did your tyres wear on your Bulldog? I only changed the last set because they were so old, and there was still a lot of tread left on them. At around the 16psi mark they had worn evenly across the tread, but only had about 15k miles on them in ten years perhaps. I think the falling off the rims thing happens below 5 psi unless you corner really hard!
You getting another Bulldog soon Tim?
Ian Streatfield, SE London and N Kent Area Rep.
Lunchtime meetings on 2nd Tuesday of the month at the Crown, Shoreham High Street, Kent from 12:30 onwards.

Robin

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Re: tyre pressures
« Reply #8 on: September 22, 2008, 09:34:58 AM »
Hi

If it helps I found that anything less than 20psi in my Bulldog 5 has a detremental effect on handling. Tyres are 185/70R14s.

Regards

Robin
Robin

istreatf

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Re: tyre pressures
« Reply #9 on: September 22, 2008, 10:02:36 AM »
The weight of a MkV Bulldog is somewhat heavier than any of the Marina based versions, weighing in at a mighty 940 kgs for the V6 cologne engine, and 880 kgs for the Pinto engine versions, around half as much again as the Marina models, according to the Pilgrim build manual. Tyre pressures as recommended from Pilgrim for these models are 28 psi, which would be about right.
I can only speak for the Marina versions from experience, where 16 psi gives a nice comfy ride, slightly sacrificing the cornering, and 20 psi gives a great sporty cornering experience at the expense of a harder ride. Either way, the tyres don't seem to wear much - first set around 35 thousand miles and only changed because of age. Second set changed after a further 15-20 thousand again only replaced because of age.
Ian Streatfield, SE London and N Kent Area Rep.
Lunchtime meetings on 2nd Tuesday of the month at the Crown, Shoreham High Street, Kent from 12:30 onwards.

Tim Hooper

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Re: tyre pressures
« Reply #10 on: September 22, 2008, 03:24:46 PM »
Either way, the tyres don't seem to wear much -................

I'm ashamed to say that hammering around all the roundabouts in Telford did have an effect on the nearside front tyre - typically around 20k saw it at the legal limit.

tim

Robin

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Re: tyre pressures
« Reply #11 on: May 05, 2009, 02:49:19 PM »
Ooops - checked I meant 30psi not 20psi. Sorry! (Bulldog MK5)
Robin