Rear tyre for Comet - Dunlop TT100 or Roadrunner?

Matty

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My Comet needs a new rear tyre - have had in the past many Dunlop SM 350X19 which soon wear flat in the middle but have at present a Dunlop TT100 410X19 which starts off more rounded, handles well and is still quite a reasonable section, though thin in the centre at 9,000 miles and seems much better "all round" than the SM.

Will an Avon Roadrunner be as good or even better please - they also seem to be £10 cheaper?
 

Len Matthews

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I'll second that! Much better choice than the 3.50x19 SM. Avoid the Made in Japan Dunlop K70 3.50x19. I had one on the rear wheel of my Shadow that wore out in no time.
 

Albervin

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The new Avons seem to be the dog's b%ll%cks but here in Australia there is little change from $500 for a set!! Whatever you put on the back make sure it is compatible with the front. You would be surprised how you can upset the handling of a bike with mismatched tyres.
 

Matty

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Thanks all - I have in the past also tried the SM and K70 both of which went square in no time.

The TT100 has been pretty good and kept its shape quite well, but will now try the Avon Roadrunner which I think I can get for about £68

Matty
 

Matty

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Thanks - Roadrunners are still commonly available - size 410x19 which is roughly 4" wide, but I have been informed locally now that the Roadrider is a better tyre. The front is a nearly new Avon 3.00x20 ribbed Speedmaster which is the correct pattern for the bike, but I am not too fussy about the rear which should really be an SM pattern - or at least was when I bought the bike in 1956 !!

If I change to Roadriders, it seems that the nearest size to replace the old 350x19 would be 100/90x19 on the rear. Is this the OK size, because the Avon chart says this is 4.3 inches wide and this is quite a bit more than the original 3.5 inches. Though the "100" figure would seem to imply 100mm, which is a bit less than 4". Can anybody explain what the true width is please.
 

John Appleton

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If I change to Roadriders, it seems that the nearest size to replace the old 350x19 would be 100/90x19 on the rear. Is this the OK size, because the Avon chart says this is 4.3 inches wide and this is quite a bit more than the original 3.5 inches. Though the "100" figure would seem to imply 100mm, which is a bit less than 4". Can anybody explain what the true width is please.[/QUOTE]

Matty, I always use the 100/90 x 19 Roadriders and am very satisfied with them. I have just measured the new one on the rear of my Rapide and can confirm that, at its widest point, it measures 3.930". There has never been a problem with clearance on either the series B or series C rear frame members.

regards, John.
 

Tom Gaynor

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Tyre sizes

I endorse John's remarks. I use a 100/90 x 19 on my twin, no RFM clearance problems.

100/90 x 19 is the "new" name for a 4.10" x 19" which was marketed as a sporty direct replacement for a 3.50 (aka 90/90) x 19. Neither the dimensions nor the conversions are exact. Bear in mind too that the width of the tyre depends on the rim size, and will differ between a WM2 and a WM3. (The 4.10 x 19 (Avon GP, Dunlop TT10 and so on) had a far rounder profile than the "square" 3.50 Safety Mileage. I've found the SM is OK in the dry, but in the wet when it climbs up on to the corner the feeling is of a contact patch about the size of a postage stamp. Most disconcerting.

If I change to Roadriders, it seems that the nearest size to replace the old 350x19 would be 100/90x19 on the rear. Is this the OK size, because the Avon chart says this is 4.3 inches wide and this is quite a bit more than the original 3.5 inches. Though the "100" figure would seem to imply 100mm, which is a bit less than 4". Can anybody explain what the true width is please.

Matty, I always use the 100/90 x 19 Roadriders and am very satisfied with them. I have just measured the new one on the rear of my Rapide and can confirm that, at its widest point, it measures 3.930". There has never been a problem with clearance on either the series B or series C rear frame members.

regards, John.[/QUOTE]
 
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