New Owner, Tire question

Not open for further replies.
Jul 10, 2004
I just bought a 72 Commando Interstate which runs very well (had a rebuild about 2 yrs ago, and has Boyer and single Mikuni). Actually, it starts on the first kick and idles quite nicely. I'll be doing some cosmetic work and sorting out the electrics. Everything works OK, just want to clean up the wiring.

This bike has the (original spec) Dunlop K81 4.10 X 19 front and rear. Rear has not much tread and the front has side damage. I see that Klempf in (MN?) has the K81's for sale. What other options for this size? What are people fitting? Avon? Where / how much? :D

Stuart Ostroff, Phila
(also BMW K1200LT, Iron Butt Assoc member)

Forgot to mention that I had another Norton. 35 years ago I went to London and bought a Dunstall (Atlas) 750 - fantastic machine, but I wish they had Boyer /Mikuni back then! Brought it back to States, had it for about a year, sold to a guy in CT.

I guess I must have a "Norton gene"

Almost forgot what it was like to ride a REAL motorcycle! My K1200LT is so damn refined, but it sure can eat those miles. Have done 46,000 mi in the last 24 months.

Stuart Ostroff
Your tire options for the 19 inch front and rear are the 4.10H-19 K-81 Dunlop (now made in Japan), the Avon Roadrunner in 4.10H-19 and the Avon SuperVenom in 100/90-19. The K-81 and Roadrunner are "traditional" OEM tires, while the Supervenom is a modern design.
tires for Interstate


Thanks.... Do you mean to say that the newer Avon is a better tire, more mileage, better grip?

Not necessarily. The construction of the Supervenom is the more rounded, lower profile than the K81 and Roadrunner. The rubber is probably the same. If you have non-modified suspension, i.e. Girling shocks and standard Roadholders, you probably will see little or no difference in handling. However, if you have upgraded the suspension, properly shimmed the isolastics, added a Norvil-type headsteady, progressive front springs, modified the damper tubes, etc. You may find the Supervenom more confidence inspiring.
I run K81's on my bikes with stock suspension and find the suspension more of a limit than the tires. On my cafe racer, it gets modern rubber (18" rear) and I'm tweaking the suspension more and more.
Not open for further replies.