Keith Walshe
Member Since: 28 Feb 2005
Location: Sydney
Posts: 53
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When the Tdv6 arrives in late June I still have an option to have 17 or 18 inch rims.
Tyre choice seems ziltch with either but the other question is which deflates the better ie increase in tread not how easy the air comes out )felt I had to add that qualification  ).
So I did a test on the 16 inch Td5 rear wheel at the weekend. Jacked the rear up, smeared the tyre with dirty water (brake dirt of the front rims  ) put clean A3 sheet paper centrally under the wheel and let the jack off. A nice tread pattern allowed me to measure the length of the contact area. Repeated in steps from 300 kPa to 150kPa. Very interesting result - the % increase in tread area is almost linearly related to the % reduction in tyre pressure ie at 150kPa (50% reduction in pressure) the road contact area has increased by 50%. and at 20% pressure reduction the area has increased by 20%.
So the question for you people with the Disco3 is what happens with 17 and 18 inch wheels and how far can you deflate them with safety.
The 18inch rim tyre has tread width 8.5% greater than the 17inch so if they both deflate by the same amount the 18 inch tyre would be prefered.
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 9th May 2005 4:25 am |
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