1970 Norton Commando 750 - looking for tires, what is recommended

David B said:

Yep, I've been running one on the front for a few years now.

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What do you run on the rear ?

Ken White said:

need help on recommended tires, my tires are good but old and am looking to replace with recommended tires. I just find confusing stats.

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i have Avons rr on and love them, the dunlop very slippy and poor

Are these K81s appropriate for a 1972 combat? Not looking for race or touring tires, just tires that are close to correct

jimbo said:

Are these K81s appropriate for a 1972 combat? Not looking for race or touring tires, just tires that are close to correct

Dunlop Vintage K81 Tires | 16% ($32.49) Off! - RevZilla

The Dunlop K81 Vintage Tires are a combination of classic style and modern technology for a higher level of durability and performance.

www.revzilla.com

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maybe this 3.60 would be better for the front?

I found my Combat handled better with a 4.10 on the front; the 3.60 made it more weave prone (K81s).
Possibly why Norton ended up going this way?

I have built a '70 previously with 360x19 front & 410x19 rear K81/ TT100's they fit fine.

If you have the old style center stand it won't work correctly unless you use the sizes I mentioned in post #5 this thread. L.A.B talked about what was original in post #10. Unless you don't use the center stand, bigger tires are a bad idea.

My ‘72 combat roadster has 100/90-19 Avon Roadriders on front and back. These are a bit wider than 4.10-19 I have used a decade or two ago and are very close to the front fender stays. I have a pair of Avon Roadrunner AM9 in 4.10-19 waiting for the Roadriders to wear out. I’m not as aggressive in the turns as I once was.

I use 18 inch tyres. I would have thought finding them would be easier than finding 19 inch. But is seems Continental make a rear tyre - I don't know about a front tyre, yet. It does not matter much to me, All I want to do is make one on-board video, but the bike will be ridden quick enough to require a bit of care while doing it.
There is a lot of bull-shit about tyres. Some guys go out onto a race circuit and almost immediately drop the bike - then blame 'cold tyres' and some guys use tyre warmers. When you ride an old bike, you should always work up to speed slowly.
A lot depends on what you ride. If the steering is neutral, you will have more lean in corners than the guy on the Manx. Sticky tyres arrived in the two stroke era. At that time, the angles of lean changed dramatically. With the older style two strokes,most guys rode them around corners with more lean while relying more on tyres. Then once they were pretty much out of the corners - blasted down the strraights.
With a road bike, you won't be doing any of that stuff. A Commando probably over-steers slightly, so would go around corners with less lean - so tyre-grip is not so important. I road-raced on old tyres for years - doing that shapes your mind. If it rains when I race, I am always in with a good chance. The other guys usually go backwards in a hurry.
Tyre pressures affect the amount of grip you have at your disposal. But low tyre pressures give more rolling resistance. So tyre pressures need to suit the scenery. If you use low tyre pressures, you probably also need lower gearing and softer suspension.- Short circuit ?
The rider adjusts to the bike, and a good bike makes a good rider,

The best deal on good looking tires that handle well are Shinko 712F or Brigstone spitfire 11F Tire patterns are similar
110-90 rear (front tire turned backwards) and 100-90 front Available in 19"

see photo

Check out the reangled Ikon flat tracker shocks on my featherbed. Rubber band is for checking travel.

I saw a friend on a new bike. Its an SV650 adventure bike with spoke wheels on tubeless rims. The rims have a flange inside for spokes to hold to but I didn't have my glasses on and I don't think they will fit a norton hub. The cool thing is the front is a 2.5x19 and it has a Bridgestone Battlax Radial 110-80-19 tire. I didn't have a tape to see how tall or glasses to read it but if you already have 2.5x19 rims its worth taking a look. We don't have inspections here to stop from running it on the rear and I don't see a reason not to if all else looks good

Luke

jseng1 said:

The best deal on good looking tires that handle well are Shinko 712F or Brigstone spitfire 11F Tire patterns are similar
110-90 rear (front tire turned backwards) and 100-90 front Available in 19"

see photo

Check out the reangled Ikon flat tracker shocks on my featherbed. Rubber band is for checking travel.

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in the UK Spitfires don’t seem to be available, and some say they have been discontinued generally.

Did Fastbacks in '70 get K81s and just "S" models get the ribbed front?

elefantrider said:

Did Fastbacks in '70 get K81s and just "S" models get the ribbed front?

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No.

According to one famous source in the Midlands the 4.10 K81 was introduced in 1971 with the introduction of the gearbox mounted centrestand, later style yokes etc.

L.A.B. said:

No.

https://www.classicbike.biz/Norton/Brochures/1970/70Norton.pdf

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I wonder how those early Roadster pillion footrests worked?

So the equivalent tire today would be an Avon Speedmaster front and rear an Avon Roadrunner 4.10?

I can't believe how proud Avon and Dunlop have become of their classic tires in recent years.

elefantrider said:

So the equivalent tire today would be an Avon Speedmaster front and rear an Avon Roadrunner 4.10?

I can't believe how proud Avon and Dunlop have become of their classic tires in recent years.

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The equivalent rear to the Avon fitted to new Commandos in the early days would be the Avon GP in 3.50x19".....but it isn't available any more.....after being deleted for at least the second time. The Roadrunner (AM9) would not be an equivalent, it is a later tyre design. The Avon SM was most often fitted paired with the Speedmaster. The SM was not a sporting tyre, square and multipurpose, it was used on solos and sidecars!

The GP tyre was introduced as a race tyre used on bikes like Manx Nortons. Only recently finally deleted.

It was what was fitted to the rear of my 1970 Fastback when purchased second hand in 1974.

Avon have become so proud of their classic tyres they have recently closed the factory that made them! Dunlop did that years ago!

As an alternative, consider Hidenau tires out of Germany. I stumbled across their booth at Barber last fall and recently put a set of their vintage tires on an old Triumph. They were tough to mount but seem to ride nicely although I only have a few miles on them so far.