Hi,

Will the 4.10 fit the front?

I hesitate to say, "Absolutely Not" but the omens aren't good ...

I've a T150 with one fitted, but I have to either deflate the tyre or remove the mudguard/fender to get the wheel in and out. And a T150 has the '69-on wider forks; your '68 has the narrower forks?

Plus a 4.10 is a fat tyre for the front of a twin, unless you're ... uhhh ... particularly ... well-built. The triples were the only bikes Triumph/BSA put the 4.10 on the front of in the days when Triumph, BSA, Dunlop, Avon, Uncle Tom Cobbley and all did lots of testing. They stuck with a 3.25 on the front of the twins well into the 1970's, even when they had disc-brake forks, and neither Dunlop nor Avon recommended wider than a 3.60 aftermarket.

Any reason why not 3.25x19 front and 4.00x18 Avon Roadriders?

Hth.

Regards,

 

I'm running Dunlop K70s on my 68 Bonneville - 3.25 X 19 on the front and 4.00 X 18 on the rear. Not sure if the K81s will work.

 

Well, I *am* a grizzly bear of a guy at 220/5'11" and broad as a barn. But not a buffalo. Haha

Honestly, I really want the original tread look of the Dunlops and figured the K81s were a nice upgrade to the original K70s for these twisty Ozarks back highways. I know performance would be better on the Avons, but I just don't like the look on a the old bikes.

 

I may just suck it up and order 3.5x19 and 4x18 K70s for the old girl.

It has a Cheng Shin ribbed front tire marked 3.25x19 on the front now with lots of tread left (just old and hard) and my calipers put the overall width at 3.82 to 3.89 going around the tire in a half-dozen places. A 4" K81 (actual width of the 4.10x19) doesn't seem that much bigger at less than a 1/4" but perhaps it's indeed much. Again, I've seen folks say no and other say yes.

Seems a shame we can't get the 3.6x19 K81 in the US. International shipping is as much as the tire on it. Ugh.