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By Barry_Q
#24115
I use Avon SM's on my Lightning. Yeah, I've noticed that the rear tyre is more 'rounded' than when I used them on my Bantam in the early 80's. Back then, the rear was far more 'square'.
By Mark M
#24116
They've been like this for a long time, the rubber compound is also improved making them a lot more grippy. It's still a very simple tread pattern so don't expect miracles!
REgards, Mark
By Spitting Bull
#24129
How long is "a long time," Mark? This is my 3rd rear tyre and the other two (one the original and one purchased about 5 years ago) both had the squarer-looking profile. So, has the rounder profile come in over the last 4 or 5 years, would you say?

Tom
By Mark M
#24132
Bull, I admit I haven't fitted an SM for a while (my tyre purchases recently have been Mitas and Dunlop Trials for the Bullets, Bridgestone for the BM and Dunlops for the Interceptor) so maybe they've changed it again? I was referring back to about 15 years ago? when the profile definitely became rounder and the compound softer. I found then that I ran out of ground clearance on an Enfield before I ran out of tyre!
REgards, Mark
By Spitting Bull
#24176
Thanks, Mark.

This tyre has a distinctly rounder profile than the earlier two I've had on the bike. So much so, in fact, that it touches the ground when the bikes's on the centre stand. The previous two were clear of the ground and the wheel would spin at tickover due to clutch drag. This is quite a significant difference I think, and I just wanted to see if I could find an explanation.

Mind you - if the circumference is a bit greater, the bike should go a bit faster :-)

Tom

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