K81s

Anyone using these remakes of the original K81 TT 100 tires? Saw them on a supplier website and was wondering if they're any good. Seemed to be priced on the same level with other quality skins for old bikes.

Mud & Snow tires. But look period correct. There are better performing tires available today if doing greater than parade speeds.

Such as?

Danno said:

Such as?

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Avons. I like the looks of the original K81's, but, with the bike being ridden every day during our riding season, good grippage/wear/safety were major considerations. See tire-choices-t17909.html?hilit=avon There's others out there who will chime in about their favorites, and there's good argument either way with the current methods of tire construction. For the most part, you get what you pay for.

Nathan

I use the TT100 GP ( which is a soft compound version) on my little Honda race bike. Excellent grip and good feel:

The K81's are not good on pavement grooves. You get a lot of steering input. With the newer tires it is smoother.

To each their own. I love the K-81's on my Commando! I've tried all the others and always come back to them. The bike handles great and the grip is plenty good to feather the edges if you want. Also good in the rain.
Just my 2 cents...

Danno said:

Such as?

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http://www.avonmoto.com/products/street-bias/roadrider

Danno,

Just watch your rim width when picking out you tires. WM2=1.85", WM3=2.15".
Pete

I ran K81s when I first put my 850 together, back in '08. They were fine most of the time, but downright scary going over drawbridge grating. That large center groove would catch on the grates, making the tire jump from side to side as it passed over each panel. This same groove liked to follow seams in tarmac and tar snakes.

Switched to Avon Roadriders (AM26) about 12,000 miles ago - much better ride. Similar tread pattern to a modern sportbike tire

Have used both K81 and Avon Road Riders, I would not characterize the Avons as lasting longer....rather shorter life than the Dunlop. As far as scary on steel bridge grates....maybe, but us former dirt bikers love this thrill. I've been using modern Avons for the last 10 years or so....Avon universal before that (K81 type). Was thinking about going back to the K81 next time. The rubber compound on the Japan ones is supposed to be pretty good and they just look right.

milfordite said:

To each their own. I love the K-81's on my Commando! I've tried all the others and always come back to them. The bike handles great and the grip is plenty good to feather the edges if you want. Also good in the rain.
Just my 2 cents...

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Ditto. I have never tried any other tire on my Commando but I like the K81's just fine and they look right to me. I have had Avon Roadriders on a Tonti-framed Guzzi and a Honda 400 Four and thought they were spectacular so that is a very good choice as well. I prefer the appearance of the K81 on a Commando though and I think the rubber compounds on the modern version is pretty good.

They came on my bike when new. They were the "cats nuts" in the day. Except for brief period when I ran Avon Super Venom's, which by the way never wanted seat well enough for me. Try as I might could never get the bead absolutely perfectly even around the rim. The K81's mount up real sweet and certainly can handle all the massive horsepower a Norton can throw at them with me at the helm.

I have k81's fitted to my 73 750. They grip ok but they do like to snake around on different road surfaces sometimes, can be daunting and used to cause me some confusion as to why i had that feeling on some roads and not others. The tt100's do look period specific but as i tell everyone if you can make it stop better and safer than im not going to sacrifice that just to be closer to the original.
I have Avon Road riders on an atlas and 88 and cannot fault them for grip and mileage. Will be converting back to Avons for the commo once i have worn these ones down.

Biscuit said:

Except for brief period when I ran Avon Super Venom's, which by the way never wanted seat well enough for me. Try as I might could never get the bead absolutely perfectly even around the rim.

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I should have added this when I originally posted.... Has any one experienced an this mounting problem with the Road Rider as I have with the Venom? Rims are stock 19" WM2.

Yep especially with 120 size rears and have had one come off after a flat fix I was in a hurry to get back to work noticting now fully centered but thot ok till almost hi sideing me at 55 and only savable d/t the triple rod links so rather pensive on my modern and vintage to pound and prode even seating. Rim locks can be a life saver once or twice life time.

concours said:

Danno said:

Such as?

Click to expand...

http://www.avonmoto.com/products/street-bias/roadrider

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Thanks. The chart clears up a few questions I had re; inch vs. metric sizes.

My front rime is a WM2x 16 Borrani shouldered alloy and measures 2 1/4" shoulder-to shoulder. It's currently carrying a 100/90 tire, which Avon apparently doesn't make. They list a 3.25 x 19 and a 90/90 x 19 both of which are 3.9" wide at the widest point. The metric has a slightly lower profile. By their math, my old front tire measures 3.9" wide.

On the rear, the Akront shouldered alloy rim is marked WM2 x 18 but measures 2 3/4" shoulder-to-shoulder. Must be mislabeled. The Avon chart states a 2.5" rim width is the minimum requirement for a 120/90 x 18 tire and that's what's on there now. It's very tight to the swingarm and chainguard, so I might go with a 3.25 x 19 on the front and a 120/80 on the rear, which is only 4.7" wide. The 120/90 is listed at 5.1".

Biscuit said:

Biscuit said:

Except for brief period when I ran Avon Super Venom's, which by the way never wanted seat well enough for me. Try as I might could never get the bead absolutely perfectly even around the rim.

Click to expand...

I should have added this when I originally posted.... Has any one experienced an this mounting problem with the Road Rider as I have with the Venom? Rims are stock 19" WM2.

Click to expand...

I have had no problems with Super Venoms or Road Riders on stock WM-2 rims. For that matter no problem with any tire used. I'm wondering on mileage, some are saying the newer type Avons wear well enough. I can get around 2500 miles to a rear and double that on the front. Not my idea of long lasting. Avon universals would go 3500 miles on the rear.

I run K81s and am happy with them, especially for grip - they're clearly a softer compound than the '60s & '70s originals and compare well with the Road Riders I have fitted to my T140 - not better, not worse.
They certainly respond to road surface changes, but it's predictable and I'm used to it - It all adds to the fun :wink:
They're totally stable when cornering and braking, so I presume it's just a function of the open 'block tread' design coupled with the modern soft compound.

One thing I have noticed is that with a 4.10 on the front I've found the handling to be better than with a 3.60. The 'Commando weave' never showed its face until I went for the narrower tyre - this was on my 850. My 750 felt OK with a 3.60 on the front. but another variable was my 850 was a Roadster and the 750 a Combat Interstate, so different riding position and steering geometry- I've found that with more weight over the front (narrower, lower 'bars) it behaved better at high speed.
My 850 is now an Interstate, and I'll be reverting to a 4.10 on the front when the current tyre wears out.

My only real complaint is they do wear out quickly, but I'm a tall heavy bloke, ride 2-up a lot and like wringing the bike's neck when I can :twisted:

Thanks all for the responses. Still undecided, but at least I have some opinions to go on.