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Discussion Starter · #1 ·
Okay, I know it's been discussed before, but I'm looking for recommendations.
I need some new tyres for my '69 Bonnie / Tiger / Trophy, thing. I want to keep a reasonably classic appearance and had my sights set on the modern Dunlop K70s.
However, it seems that a lot of people don't like them, complaining of vague steering and tramlining. So, how about the current incarnation of Dunlop TT 100's or Avon Roadrunners? I'd be looking at 3.25 x 19 front and 4.10 x 18 (or equivalent sizes).
Any thoughts?

Thanks,

John
 

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John, try a 3.60 x 19 and a 4.10 x 18 Dunlop TT100 K81 pair. Still looks good and grip is superb for the A and B roads. They tend to be well in balance and needing very little,if any, balancing. Avon Roadriders are also superb tyres but seem noticeably heavier. I used the TT100s for many years on my T120 but was able to buy some Avon tyres at a lot less money so bought those now.
Davy recommends the Continental attack for super grip and braking but it just depends if you are a bit of a racer.
 

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I'm pretty happy with the Avons I've been using. However, OCR made a comment about going to the Contis was like the difference in a telegram and an iphone. Might go that way when it's time.
 

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Hi John,

need some new tyres for my '69 Bonnie / Tiger / Trophy, thing.
If your "thing" has Triumph drum-brake forks, your biggest (or smallest, depending on your definition :)) problem is the clearance between the fork legs - modern tyres' overall widths are greater for the same numbers moulded on the sidewall. :(

3.25x19 K70 (or contemporary Avon SM) will fit but I've had bad experiences with both and personally wouldn't touch them even with someones else's bargepole.

As long as the bike has '69-on fork yokes (6-3/4" legs' centre-to-centre distance), a 3.25x19 Avon Roadrider will 'fit' but it's a similar overall width to a 4.10 K81/TT100, so you have to either deflate the tyre or remove the mudguard and brackets to get it in and out. :( A 90/90x19 Roadrider has a more similar width to an original '69 3.25 Dunlop, 90/90 is also the metric 'equivalent' of 3.60, as suggested by "rambo".

The narrowest Conti ClassicAttack 19" front is 100/90, and they're another 10 mm. wider overall than 3.25 Roadrider or 4.10 K81. Pictures of "OCR's" Daytona show different forks and yokes from standard Triumph; if the legs are further apart than standard Triumph, any 100/90 will fit easier.

I personally haven't noticed any difference in 'feel' between Roadriders and K81/TT100's. So my choice of Roadriders is unashamedly jingoistic - Avon research, develop and manufacture in GB, Dunlop don't do any of those in GB.

Hth.

Regards,
 

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Hi John

I have the Dunlop K81's which were on the bike when I bought it (1970 TR67). I have found them to be very good, no tracking and good grip (although I don't ride as hard as Rambo and others:wink2:). I have a friend who loves the Avon Roadriders.

Safety comes first, of course but if there is nothing to choose between the Dunlop and Avons then I prefer the look of the Dunlop's to the Avons on a classic bike.

I personally haven't noticed any difference in 'feel' between Roadriders and K81/TT100's. So my choice of Roadriders is unashamedly jingoistic - Avon research, develop and manufacture in GB, Dunlop don't do any of those in GB.
Yes but Dunlop used to. My first flat tire was on my 1959 SpeedTwin in '73, the tyre was a Dunlop and the whole of the one rib had stripped off. Since I lived in Birmingham I took the tyre on the bus to the Dunlop factory and asked them to replace it since it was clearly faulty. They checked the tyre in their lab and denied any responsibility, and they also refused me a replacement even as a gesture of good will. So some things don't change!

Steve
 

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It depends a lot on where and how you ride. I ride my older bikes mostly on Illinois county roads, that are primarily oiled, with pea gravel spread on them, so I will encounter areas of loose pea gravel. The K70's work best on those surfaces, and at speeds under 60mph. My 2014 T100 came with Metzler Lasertec, and surprisingly they do ok on the back roads, and at speeds faster than I like to ride. I've road bikes that have the TT100's, and I do not like those on anything other than smooth surfaces.
 

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If you’re not going to show the bike in shows where they would deduct points for tire choice you should really think about this. There are much better tires out there than K70’s and the rest of that old stuff, and nobody else notices or cares what tires you have. Modern rubber is in your best interest.
 

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Appear to be many who don't like the K70s and I respect their opinions, but they're still my go-to tires. I figure I've done 40,000+ miles on packed and loose gravel roads in Quebec and Vermont and they've never let me down. Not so much now, but I used to hit 70 pretty regularly on The Gravel. No one looks at your tires... unless they're K70s - that's the cherry on top.

Different strokes for differnt folks and riding conditions.
 

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I don’t dislike k70’s, I just think you can do better these days. They’re very controllable while you’re sideways, but I try not to do that on a street bike. They have good stability on dirt, too. It just depends on your priorities. Mine is keeping the pucker factor down on paved roads. Sliding sideways on dirt is fun. Sliding sideways into oncoming traffic, not as much fun.
 

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I have no preference between the Avon and the Dunlop K81. What i did find with K70 is they were good on gravel track riding but poor on low speed cornering with wet road tarmac. They did slide sideways and it was the front tyre and that can result in an instant bike down. No issues at all with the newer designs and profiles and i suspect there are many other road tyres equally as good. Looking around the local club bikes, the majority use Avon as it has a good price followed by the K81 and then there are some cheap European tyres at half the price. Many riders say they are good but who knows what riding style they have.
Some of the show standard bikes on club runs use K70s but they are usually riding very slow compared with quite a few others in the 100 bike pack.

Downside of the K81 rear is when it wears after about 3500 miles, it will begin tracking on road lines. That is when i take them off. The Avon wears at about the same rate.
 

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Discussion Starter · #14 ·
Thanks for all the input, gentlemen.
I think I may go with the K81-TT100. They will still look fairly correct for the year and most that have used them seem fairly happy with them.
Nearly £200 for a pair is a bit of a shocker, though.

John
 

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Discussion Starter · #16 ·
Look at the cost of a pair for a newish bike. You'll think the TT100s are a bargain.
Not sure about that.
I recently picked up a new Michelin Pilot rear tyre for my neighbour's XJR1300 and it was less than £90.00.
Also, I just put a pair of tyres on the rear of my Mustang for around 75% the cost of a pair of TT100's.
Still, I guess that's the price we have to pay for riding something a little different.

John
 
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