Author Topic: Dunlop K70 tyre life, only 3000 miles? What lasts better?  (Read 1299 times)

Online groily

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Thanks Mike, MT60 yup.
Heavy braking potential just isn't something you get with a sls Matchless-wheeled P11, so no worries there! But the tyres fit easily on the rims and between forks and s/arm (with the correct guards), no worries there either - and I have found them better than what I had before.
Not a rational choice for an A though I don't think, except maybe on the Spitfire Scrambler types.
(With security bolts in this case!) But most rims aren't drilled for them are they? Maybe they all should be  . . . .?
Bill

Offline BSA_54A10

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You have to be careful with Dunlop tyres.
They are made in several different countries using the same tread pattern but different compounds.
The ones from Japan fitted as new bike tyres are fairly hard & give excellent wear.
The ones made in France or Ireland got used by the classic racers cause they stick to the track but are scrubbed bald after a single meeting.
When Scott's had the tyre shop in Goulburn St I used to get them to put aside the Dunlops that new owners wanted changed & we bought all of them for the courier fleet.

The trouble now days is most bike shops have no idea what tyres they are fitting apart from what is written on the side walls.
It pays yo go to a specialist motorcycle tyre shop and not your local parts supermarket.

The story with Bridgestone battle axe was the same.The ones fitted as OEm wore really well & gripped OK.
The ones bought as tyres wore the center tread down to the legal limit in a couple of months if you were lucky and just below if you were not.
It would not move from this for a full 6 months of courier riding and when pulled over for a safety check usually you could bluff your way out of it.
Bike Beesa
Trevor

Offline RogerSB

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I imagine I’ll probably be sent straight to Coventry for this but I have Dunlop Gold Seal K70s front and back on my 1960 Golden Flash and (as yet) I can’t complain. The tyres were on the bike when purchased over 2 years ago and looked reasonably new and unworn. I’ve covered 1,400 on them and I can’t see signs of excessive wear on either front or rear (see photo taken recently).

Maybe it’s down to style of riding but since having them on my A10 the important thing I have learned is that they do not tolerate either under or over inflation. We know that excessive over inflation will cause the centre to wear more than the edges and excessive under inflation will cause the edges to wear more than the centre and that under inflation also results in cupping.

The other important aspects are: Over inflation will produce a smaller contact patch with the road surface with the resulting less grip and a harsher ride. On the other hand under inflation will increase the contact patch but will cause the tyre to flex too much producing skittishness and too much heat, which will likely damage the tyre’s structure.

Also very important and sometimes overlooked is that tyre pressures need to be worked out according to the individual load being carried and within the limits of the maximum load and psi stated on the tyre wall and the way to do that accurately.

This is what Dunlop replied to one of my email to them last year when querying my K70 pressures:- 
The K70s manufactured today uses modern materials e.g. compound etc. but the internal casing remains a crossply construction and as they are designed for older classic bikes their design takes into account the pressures used at the time.

1960 Golden Flash

Online Black Sheep

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In fairness, the one I wore out in 1200 miles was on a Highland tour with my modern-mounted sons, not hanging about. I still wouldn't have another K70 though.
2 twins, 2 singles, lots of sheep

Offline Triton Thrasher

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Quote from: RogerSB
This is what Dunlop replied to one of my email to them last year when querying my K70 pressures:- 
The K70s manufactured today uses modern materials e.g. compound etc. but the internal casing remains a crossply construction and as they are designed for older classic bikes their design takes into account the pressures used at the time

They hardly ever say  suchlike as “We’re selling quick-wear tyres for a laugh!”

Offline Slymo

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My SR came with new Avons front and back but when they are worn out I'll put Mitas tyres on. Loved them on my B44. They are a soft compound so stick well to the road and are cheap enough that I can replace them without a mortgage. The only pity is they make a lovely 18" front tyre with a beaded tread but at 19 you have only a block tread version.
NZ

Online KiwiGF

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My SR came with new Avons front and back but when they are worn out I'll put Mitas tyres on. Loved them on my B44. They are a soft compound so stick well to the road and are cheap enough that I can replace them without a mortgage. The only pity is they make a lovely 18" front tyre with a beaded tread but at 19 you have only a block tread version.

Where do you get your Mitas tyres and how much? I’ve only got a requirement for 19” so far, but have got a 21” front rim for my b31 when I finally get around to spoking it. In a search for something better than k70s i bought rears of “Duro” brand from classic tyres of Tauranga, but they are not the easiest to deal with.

Note: re other posts on tyres, we don’t have much choice or availability of the “main” brands in nz eg Avon etc.
New Zealand

Last had an A10 in 1976, in 2011 it was time for my 2nd one.

1956 Flash Frame EA7-168x Eng. CA10 913x, left BSA together for Liverpool, 5th Dec 1955.

B31 “hot rod” (yeah right)

Armstrong Siddeley Whitley for rainy days (with wife).

GL1800 Goldwing not sure why yet

Offline Slymo

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Dold Industries in Te Rapa are the agents so a look at their website might give you a local provider.
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Offline Rocket Racer

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I recently fitted a set of avon SM mk2's to my vincent (as pretty much all thats available in a 20" front), I've been really impressed with them both , they are made in modern compounds and grip very well and did some good hard work for me without showing any evident wear. Speeds greater than my B33 is even capable of under its own steam... I'll be looking to fit equivalent rubber to my road rocket and the B33 in due course.
just my 10c worth
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
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Online muskrat

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G'day RR.
Not much lean angle on them. Your too used to riding bolt upright LOL.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
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Online Black Sheep

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So you may think. You can get plenty of lean on these Avons. You need a fistful of throttle when scraping a footrest to make them drift.
2 twins, 2 singles, lots of sheep

Online bsa-bill

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You need a fistful of throttle when scraping a footrest to make them drift.

What kind of tread have you got on the footrest then  *smile*
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Online Black Sheep

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Slicks of course! *smile*
2 twins, 2 singles, lots of sheep

Offline Rocket Racer

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With my B33 and A65 I typically find the mufflers and pegs are the limiting factor, not the tyres. On a race pegged bike a different story, but on the vin we did some real twisty roads and fast sweepers and the tyres tread pattern wasnt the limiting factor.
Yes appreciate I normally ride with a training wheel on my race a10 but I do enjoy spirited road riding and think you'll find if you lean the bike until its run out of ground clearance (laden with a rider) there is still tread on the deck. Nothing wrong with predictable slides...
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
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Offline mikeb

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I do enjoy spirited road riding
yes i can attest to that RR - recalling one ride where the only way to keep following you on your B33 was to follow the oil smoke behind you, and you were two up  *eek*
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'61 Super Rocket  - '47 B33 -  '18 Triumph Street Triple RS