Author Topic: Dunlop K70 tyre life, only 3000 miles? What lasts better?  (Read 1301 times)

Online KiwiGF

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Thanks everyone, I've had to bite the bullet due to the need to get a tyre delivered in time for the bsa rally in a couple of days time  *beer* *woo* , and I've bought a "Duro"  HF308 in 3.5x19 (133 nzd).

Others experiencing a life of 3000 miles from the k70 made me rule out getting another one. The handling gets iffy well before that as the tyre squares off. It's not a "safe" option in my opinion.

In about 12 months I will be able to report on how the Duro wears (if I'm not beaten to it by another forum member), the Duro is very similar in look to the k70, at first I thought it was a copy.

If the Duro's grip is no good I will report sooner, hopefully not from a hospital bed  *shh* *sick*

Just my 2 cents worth but I reckon every forum needs a "tyre thread"  *smile*  *fight* (as well as an oil thread), at the very least we should be able to get a consensus on tyres to be avoided  *pull hair out*
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 mikeb

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Kiwi I'll look out for you in 'the naki', and examine this new Duro you've bought. there's a bunch of us coming south from Auckland on Friday (safety in numbers - and more spare parts carried between many). the weather is looking good and should be a great rally  *smile*
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Online KiwiGF

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Kiwi I'll look out for you in 'the naki', and examine this new Duro you've bought. there's a bunch of us coming south from Auckland on Friday (safety in numbers - and more spare parts carried between many). the weather is looking good and should be a great rally  *smile*

I'll look out for you as well Mike, are you the clubs facebook group site? There are some details of where people are meeting up, but no meet up details for aucklanders yet. Try joining at https://www.facebook.com/groups/NZBSAMOC (sorry non kiwis, group is for nz club members only).

It's looking so good weather wise I'm thinking of travelling real light and not being prepared for poor weather, however last time I tried that I arrived at the kaiapoi rally site totally drenched and suffering from hypothermia.........darn those weather forecasters  *bash*

Back to tyres, the Duro has 5/16" of thread versus the k70 1/4", so it's has a third more usable thread and costs almost 2/3 of the k70 (I actually paid more like 110nz for it). I'm pretty certain it should be cheaper than that looking at what they go for in the USA.
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 Tomcat

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[quote author=KiwiGF

Just my 2 cents worth but I reckon every forum needs a "tyre thread"  *smile*  *fight*





Yes, good idea  *smile*
'48 A7 '59 SR '74 850 Commando TDM900

Offline Rocket Racer

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Getting off topic, but re this week end the northerners (from Drury to Whangarei at last check) have a starting place and time organised, anyone who missed the last clubnight and needs filling in send me a pm.  *wink2*

I put tt100's on my super rocket but in hindsight don't think they suit the bike and would go for something else with a traditional pattern, but odds not a K70.

See you in Inglewood Friday arvo fellow kiwi riders 

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 KiwiGF

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A bit more info on this topic I started.

Well today I fiitted a “duro” brand tyre to my b31 (rigid) in preparation for a round trip of around 800 miles to the nz bsa National Rally next week. This replaced a worn k70.

The k70 was the (new) tyre I fitted during building the b31 basketcase up from parts, and registering the bike for the road not much more than a year ago. It was embarrassing that the WOF (MOT equivalent for you Brits) tester pointed the worn tyre to me before passing it as “marginal” but good enough, it had not even occurred to me to check the tread depth after so few miles. It looked ok but using a depth guage told a different story.

The Dunlop k70 has only lasted about 2000miles before being down to 1mm in the centre in some places, a bit under 2mm in others, and would have been bald by the time I got back home from this years rally. The tread on the edges is hardly worn so maybe I’m not the “scratcher” I thought I was eh.

About the only positive thing to come out of this was how easy it is to remove a tyre that is still soft and flexible which of course it should be, being not much more than a year old. Even the fitment lube was still there and not dried up. I only needed to use one tyre lever to get it off.

What a rubbish tyre life that is. I won’t be buying another Dunlop k70  *conf*





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 Triton Thrasher

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Almost any tyre lasts longer than a rear K70.

Online RDfella

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As with most things in engineering, there's a compromise to be made. Softer rubber will wear quicker that harder rubber, so one has to decide - do you want grip or long tyre life? I always used K70 for hillclimbing, as it outgripped the so-called racing tyres. Just another thought, if the centre is wearing badly, tyre pressures may need to be dropped, not raised. I run 18 - 20 on the back of my (rigid) M21 and 20 - 25 on my other (non lightweight)  classics.
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.

Online Black Sheep

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I found K70's gave poor grip, wet or dry. I had some bum-nipping slides on dry roundabouts with them. My last one wore out in 1200 miles. Avon SM MkIIs are superior in every respect.
2 twins, 2 singles, lots of sheep

Online groily

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Just replaced a K70 on a Notrun this afternoon - it did just on 3K miles on a 650SS and was well dead. TT100 on both ends now, and we'll see.
Avon Roadriders are nice but look a bit funny to me on oldies. Had them on a café-racer and they were pretty good on the bendy bits, but out of place maybe on most classics in more standard trim.
SMs on a couple of all-year workhorses have done pretty well, and I also find they handle OK with my fat backside holding things down. On the A I was getting about 5-6K miles on rears - a TT100 on there now is half worn at about 1800 miles though.
A tyre I do like is the Pirelli Scorpion for rims that will take one - that's not 19" wheels I think. A similar-ish 19 inch Pirelli MT-something is OK too - but short life is guaranteed on the bike I have these things on (P11 desert sled). And the look of them isn't exactly period either. I think Ducati fit them on their Scramblers, or did, and they're pretty OK on the road (how many of those bikes ever go off it, for that matter?)

I'm going to stick with TT100s for the time being on the A, the Notrun and one AMC twin, having bought a car-bootload last time I passed Vintage Tyres in the UK. Pirellis for the P, and SMs on 2 others for economy reasons. Haven't tried Mitas - but a lot of friends like them, price-wise they're good and they seem to last pretty well. I rode a pre-unit Triumph with them on and it seemed fine - but it was a bike I'd done the engine on for someone else, not mine, so didn't explore the limits.
No risk of tyres cracking up or going out of date before wearing out round here, so I suppose that's something! But if there is one job I just don't like these days, it's tyre fitting  . . . Is it the compounds, or what? Used to be able to get new ones on without levers almost every time - but not nowadays. Feeble with age? Or they're made of less forgiving stuff maybe.

While I'm on, since having a blow-out on the A a couple of years ago on a dual carriageway, I now only fit Michelin 4mm thick inner tubes, for scrambles I believe, to everything in the shed. And I always replace them with each tyre change, plus new rim tape. Bloody difficult sometimes to get them into front tyres - but no more problems with sudden deflation and/or valves ripping out on some of the tubes I've had in recent years (from god knows where probably). Could have killed me when the rear SM went on the A - glanced off central armco barrier and then off a concrete near-side barrier while getting the thing under semi-control with the  tyre blown clean off the rim and the back hanging out 45° from straight. The extra cost of the heavy-duty tubes is worth it - and a hell of a lot less than the new rim, spokes, tyre etc etc that I had to sort after that incident.
Bill

Online chaterlea25

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Hi Bill and All,
Totally agree about using quality tubes
I had a big bang experience on a Morini
In 2001,  *eek* that put some age on me *ex*
Do you or your friends have any experience of the  "own brand" tyres sold by
"Chambier" over there in France?
Apparently made using the Michelin moulds ???
Prices arevery keen too  *smile*

John
1961 Super Rocket
1963 RGS (ongoing)

Online groily

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Hi John,

Hmm  . . . but No, I have no real knowledge. Tyres for 25 bucks don't seem too bad though.
Maybe just the ticket for machines that need something period, and aren't going to be hammered  . . . dunno.
Chambrier 'père & fils' are well-known here, and travel the land with a posh articulated truck full of bits and pieces, selling at autojumbles all over the place.

To be honest, I think I'd tend to stick with known-brands for most things. I don't have any bikes that just 'need something to keep the rims off the tar' so they can be set in motion for, eg, exhibition purposes and gentle strolls.
Most of the road-going locals looking for 'best value' seem to go for the the Mitas. Quite a few SMs, TT100s etc etc too though- and Vintage Tyres have a French service. If you ring them from here, they answer the phone in French, and they will ship any order over £100 for free I discovered, having turn up in person to buy a year's worth!



Bill

Online muskrat

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G'day Fellas.
I still love the RoadRiders. Their not cheap and don't last long and don't look period but I'd rather have skin on my butt than money in my wallet.
Why is it I can put 4 tyres on the ute for less $$$ than two on the bike?
Cheers
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Online Black Sheep

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Don't forget security bolts. If you get a blowout, they keep the tyre on the rim.
2 twins, 2 singles, lots of sheep

Offline mikeb

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roadriders for me too on the A and B. sticky, good on the twisties and last a lot longer than your K70. the profile is a bit low tho.

Quote
A similar-ish 19 inch Pirelli MT-something...
that's the MT60 on ducati scramblers. i took them off the scrambler i had as they were squishy at the front under heavy braking and could slip at rear when applying wrist out of a bend. they are also very wide so i'd be surprised if they fit our rims

Kiwi I think the real problem is the amount of wrist you use and the awesome power of the B31  ;)

And Musky the tyres on your ute are probably made of wood, and not made in europe
New Zealand
'61 Super Rocket  - '47 B33 -  '18 Triumph Street Triple RS