TR6 trye sizes

[Twink1598]

I'm hoping that someone will be able to advise me. I have recently acquired a 1975 TR6 that is fitted with an assortment of 205/60 15 tyres on the standard steel rims. As the car has been standing unused for many years, these are now approaching the consistency of rock, and I therefore intend to replace them. However, is there an advantage in running a slightly narrower tyre,and if so what size would you recommend.

Thanks in advance.

Mike

[tapkaJohnD]

Mike,
You need the mintylamb wheel and tyre Comparorama:

http://www.mintylamb.co.uk/?page=tyre.htm

You will soon see that you need to change not only tread width (eg "205"), but the wall ratio (Profile, "60") or else the rolling circumference will be changed and you will loose calibration of your speedometer.



John

Edited by tapkaJohnD on Tuesday 30th July 23:20

[Twink1598]

Thanks for the link, I've not seen that before. My problem is I don't know what the original set up would have been, so can't tell what the rolling radius should be for the speedo to be correct. Saying that it only gives a rough range of possible speeds at the moment in any case.

Mike

[garagewidow]

http://www.triumphexperience.com/phorum/read.php?2...

bit of finger crunching shows the above,how correct I don't know but you should be able to compare sizes with minty lambs calculator.

Edited by garagewidow on Wednesday 31st July 01:26

[Silvertop_John]

I'm running 195/65 on mine. When I bought it, the tyres were 205s, and that really seemed to be too big, and they fouled the rear damper conversion I had installed. There doesn't appear to be much speedo error with the 195s.
I think the original fitment was 165/80 on 5 1/2 rims, although the US market had 185s as standard.

[Twink1598]

Thanks guys, i think the. 195/65 might be the way to go.

Mike

[Yertis]

195/65 here, though I'm thinking of going back to 205/60 next time. I think wide tyres suit the TR6 for some reason.

[tapkaJohnD]

Twink,
Original tyres were 165/15s, cross ply of course, with a 82% wall ratio.
Stick those numbers into the Comparorama!
JOhn

[Twink1598]

Many thanks for the advice guys. 4 new Yokohama 195x65 have transformed the car.

Mike

[jellison]

205's way to big for a 5.5 J original rim. They are OK on 6j's and Perfect on a 7J.

I need to look for some 155's tyres for an old set of TR6 rims (the originals), so I can pop these on my new TVR (same pcd) so I can get it on the same small trailer.

Edited by jellison on Monday 26th August 11:24

[Yertis]

jellison said:

205's way to big for a 5.5 J original rim. That are OK on 6j's and Perfect on a 7J.

They are a bit too big, although I never had any problems. If I go down that route I'll be getting some 6j's.

[MisterT]

tapkaJohnD said:

Twink,
Original tyres were 165/15s, cross ply of course, with a 82% wall ratio.
Stick those numbers into the Comparorama!
JOhn

Cross ply tyres were never fitted to TR5 or TR6.

UK spec cars were fitted with 165HR15.

US spec TR250's and TR6 had 185HR15.

I fitted 195/65x15 to my TR6 on standard rims and it looked just right and didnt seem too heavy on the steering, handling and grip was good but it was 'tied' down with a Revington TR handling kit which included revised spring rates and dampers mounted inside the rear springs.