Greetings fellow K-bike :pirat:

I have reviewed more posts about tires (tyres) than Carter has liver pills

Would someone please give me the straight dope on the best all around tire for 1985 K100RS, especially for a wet climate like the Pacific Northwest (US), where the riding season can be year round, or at least 10 1/2 months out of the year.

I am currently running Dunlap 100/90-18 on the front, and don't really like it. It is too prone to follow the grooves in the pavement. And a Metzler 130/90 V17 on the back, I like it, but the rear end likes to slide around too much for for comfort.

Thank you everyone, as you know I am new to this forum, and I look forward to being able to share my own experience with y'all soon.

Cheers from the great northwest, and I include British Columbia in that :queen:

Welcome to the asylum.
You've just started one of the most favourite topics on the forum.
The bottom line is suck it and see. Everyone has their own preferences. Don't listen to the Aussies, they're spoilt for weather. 30C!
Your climate sounds like ours in Ireland.
My personal choice would be Bridgestone BT45's or Michelin Active Pilots.
The Bridgestones are good, but I find the Michelins almost as good with better mileage.

I had a michelin on the back and a pirelli sport demon on the front on my LT. Got a new set of the sport demons and I have never had a moments concern on them even in the wet. Reported mileages are good too early to say on mine after 4k miles they are still young looking. I couldn't reccomend them highly enough.

88

I've ridden on Metzeler, Continental, Michelin, Dunlop and Pirelli on 8-valve K-Series.

The Dunlops, which were radial-ply and no longer available, were the best. Of the rest, lately my favourite is Pirelli Sport Demon.

Having said all that, the problem, other than personal preference and riding style is the surfaces/construction of roads where you live. Road construction varies according to local conditions and that will affect the way that the tyres perform (both in terms of grip and wear rate).

I have used the BT45's but found that they cracked at an alarming rate very quickly. They looked after a short while as if they were a very old tyre They were what the PO fitted and I replaced with the same which went the same way.

I am now running Michelin Activ Pilot, over-sized on the back and standard on the front. So far so good lots of grip and are performing well in all weathers. Chicken strips show I have just a bit more lean available to me if I need it too....

I'm taking a razor to my chicken strips on my new tyres so I don't get bagged out by the bike shop when I have to get new ones.

Take the wheel off and when you take it in tell them it's for your dads bike and they wont bat an eyelid.

As well as still trying to Wheelie an LT I am also trying to get my knee down to loose the Chicken strips.... Deff good to know we all call them the same thing around the world!

On my BT45's I did find that the center of the tyre wore less than the section on either side... I did contemplate increasing the pressure but with the cracking I really didn't want to push it too far.

twincarb wrote:

On my BT45's I did find that the center of the tyre wore less than the section on either side... I did contemplate increasing the pressure but with the cracking I really didn't want to push it too far.

BT45 are dual compound tires (The sides are softer than the center).
Riding with the correct air pressure is critical. I had a front BT45 missing 5lbs of pressure and after 2K, it had to be replaced. The sides were scalloping.

Hi all Right now I have Metzler's (140/80-17 and 100/90-18) on the 85 RT
How much over size can you go on the rear tire? Mine is looking kind of square and the weather is starting to turn all most 45F today very frostie right now.
thanks G

A 140 rear is already oversize for your bike.

The issue with increased tyre size without the equivalent rim is that the tread area will be out of shape, domed towards the centre.

You then have to balance the advantage of a slightly increased tread area against the fact that the profile will not be as intended and likely increased wear down the centre. The wider you go, the more pronounced will be the altered profile.

Comberjohn wrote: Don't listen to the Aussies, they're spoilt for weather. 30C!

And loving every minute of it.
I run Metzler Lazatech rear and Perfect front. I don't need to cut of the rubber from the chicken strip. I let the road do that

MikeP wrote:A 140 rear is already oversize for your bike.

The issue with increased tyre size without the equivalent rim ...

From memory ... the limiting factor in fitting oversize tyres on my '86 K100 was tyre to drive shaft housing clearance. I stand corrected, but even if you find a wheel, the tyre may not clear the housing at the gearbox end of things.

Avon Azaro just clears the housing by a few mm. BTW this is the only radial tyre that I could find to fit the rear wheel.

larrikin wrote:

Comberjohn wrote: Don't listen to the Aussies, they're spoilt for weather. 30C!

And loving every minute of it.
I run Metzler Lazatech rear and Perfect front. I don't need to cut of the rubber from the chicken strip. I let the road do that

Oh come on, you can hardly say that this summer was perfect in Sydney... temp just ticked over 30C and it even rained some days It was bloody hard to decide on what to wear

I have driven about 450km now with new Michelin Pilot Active tyres. Old tyres were, well old, I mean really old - and shape was gone (flat in the middle) and I have not driven any other K100. But to the point. With these new tyres my flying brick seems to have lost it's brickness. It is just flying. And I have taken it easy since there is low temperatures here and sand after winter at corners etc. And of course because they are brand new.

I still must say that I really like these tyres and if they last atleast 10 000km rear and say 12 000km front I will definetely buy same type of tyres next. (Unless I make my K more Off Road vehicle - then I shall buy some off roading tyres...)

I have to say that the durability of Pilot Actives was a bit of a disappointment. Here is my rear tyre after about 7000km (with 6500km 2,6bar pressure and rest testing with 2,8bar):

https://dl.dropboxusercontent.com/u/58323882/DSC_0210.JPG

Don't know what the roads are like in Finland, but reckon they can't be worse than the UK roads. I have not tried Michelins on my K100LT so can't comment on the wear rate you have experienced, but I share your disappointment.

I have just put another set of Avon Road Riders (front and back) on my bike as I have had been pretty pleased with their performance - both in road handling (wet, dry and icy) and wear rate and they were a good price (£162 for the two). I changed the rear tyre because of the puncture (screw) picked up on the way home from work last week and the fact that the tyre was close to it's tread limit anyway. I changed the front at the same time because I need to replace the wheel bearings and it was easier to get a new tyre on my spare front wheel (and keep riding) and do the bearings slower time.

This is the condition of my old Avons....

  

Rear: Remaining tread ~ 1.8 - 2mm                                          Front: Remaining tread ~ 2.5mm (another 2 - 3k miles?)
Rear tyre mileage 8000 miles (~12900km)                                Front tyre mileage 12215 miles (~19600km)

New rear tyre tread ~ 6mm                                                      New front tyre tread ~ 5.5mm

Avon Road Riders seem to get bad press, but don't know why. I was going to go for BT 045s this time round just to see what they were like....but a pair of them would have cost me another £50 (which I spent on fork seals, wheel bearings, rear brake pads, fork oil and spline lube instead!) so I stuck with my known knowns.

Roads in Finland at spring have very rough tarmac since ice spikes on cars wear them. This might be one reason for heavy wear rate. I have ridden two springs with Actives.

A 140/80-17 tyre is perfectly acceptable and legal on a K with the 2.75" width rear wheel. It says so on BMW literature (RSD), as well as on the tag under the seat on my late '86 K100RS, and we've been fitting these with success for many years now. The standard size, of course, being a 130/90-17. I've also used a 110/80-18 bias ply up front - running three spoke with radials now, but that's another story. The best fit for me and the roads I ride using bias or cross ply tyres are the Pirelli Sport Demons. They stick in the rain and the dry, they wear acceptably, and they handle exceptionally.

As the old tyre monger I knew used to say, "Sticks like glue, wears like iron!"

I always dread reading this very subjective issue as I have used Avon Road riders and the old road runners for the last 25 odd years with no problem. They never seem to get a mention. Great wear rate and don't white line when getting towards the end of their life, unlike Metzler and Continentals. I presume they are 'old school' but they suit me and have never given any trouble in all year riding.  John

I've been running Avon radials for a month now and really appreciate the ride. Obviously we have different road surfaces to deal with here in the great northeast, and I don't ride in the rain when I can help it (gets the bike dirty!). But, having lived in Seattle for many a year I feel qualified to say that a switch to radials makes a world of difference in the old '85s. 

I'm sure you've seen the posting on skinny radials, for the record here it is again: https://www.k100-forum.com/t7472-skinny-radials

Radials really stick to the road better. We have a large number of freeze-cracked roads here, and bias ply's tend to hop or jump when going over them, making cornering very uncomfortable. But, radials absorb the small flaws in the road and provide greater stability even in cornering. No more clenching of the teeth when riding on rough roads. No more worrying about pot holes when riding at higher speeds either.

Last year I rode on Bridgestones, which were duo-compound tires. On the freeway and at speed I felt a bit disconnected from the road. When the tires were new the hard compound was well rounded to the point where I had to make a conscious effort to keep the bike on the straight and level. By the end of the year when the hard center had worn flat, the transition to cornering became noticeable--again bringing uncertainty.

Even though these radials are skinny I really like the "plant" while riding at speed. The bike feels extra stable and the suspension doesn't work as hard as before. Cornering feels slightly different in that the tires give gradually, providing constant feedback that is confidence-building. There's no slippage in the corners even whilst encountering a slight gravel patch (fairly common in some places around here).

There are a couple of varieties I've listed that should produce very good results on wet roads. The forum has already decided that radials will work on the older Y-spokes, just make sure  from specifications they'll fit your rim size (the table was constructed for the wider rear tri-spoke rims). I wouldn't worry too much about the cross-over aspect of several listings, a 90-10 or 80-20 is not a real off-road tire IMO. 

Some of these tires were made for the later BMW GS, etc., and I really think you can't go wrong with a new set of radials.

+1 on radial tires for any K bike.

Better handling and smoother ride.

PaulLipscomb wrote:
Rear: Remaining tread ~ 1.8 - 2mm                                          Front: Remaining tread ~ 2.5mm (another 2 - 3k miles?)
Rear tyre mileage 8000 miles (~12900km)                                Front tyre mileage 12215 miles (~19600km)

New rear tyre tread ~ 6mm                                                      New front tyre tread ~ 5.5mm

Damn, how do you do that?  I just replaced my rear tire that was showing a good amount of cord.  It had about 5,000 miles on it.  I believe it was a Metzler Z8 or something.  160/60-18. (1992 k100rs)

Anyways, I'm jealous.

I have just put a new set of Michelin PR2s on my K1100 and got 22500 from the previous set.

My general rule of thumb has been 20,000km front and 12,000km rear.  I don't seem to vary from this much except for the dirt tyres (shorter) and the sidecar car tyres(much longer.

I remember a Michelin touring tyre(M66 ?) in the 80s that I tried on my XJ900, it went 23,000kms but would spin under power on most wet hills, it was truly horrible

Al

I have been talking to fellow riders and they believe that reason for the rapid wear of my Pilot Actives was too low pressures. These newer tyres seem to need 2,5 - 2,7 bar front and 2,9-3,0 bar rear. Will try that with next tyres.

(Edit: I had 2,3/2,6 bar).

I have PR2s and have had to go to 2.7 and 3.0 to get good wear.

Just bought from Motorcycle Superstore  a mis-Price on an  Avon AM26 Roadrider REAR Tire 140/70v-17  $11.87 Shipping included.  Price will hold until they correct it.
Yes, I realize the height is a 70 not an 80.  So the rear will sit a little lower and the speedo will be a few more mph off.

I've had  Sports Demons on for a while now, the back seems to wear out in the middle, I'm trying a little less air,front is scalloping so putting a bit more in. I was whingeing about lack of mileage, having to get a new rear. When I checked the books, I've done 15,000 on them both. Can't complain about that.
I am a renown pussycat rider.

Looking at a set of Shinko E705 dual sport tyres.

Will a 120/80/18 fit the front?

Just concerned about the width.

Can get a set for $275 so cheap enough that if they are crap then no real loss.

I have a spare set of wheels and will just swap them to the bike if I think a ride might include a bit of dirt.

rosskko

rosskko wrote:Looking at a set of Shinko E705 dual sport tyres.

Will a 120/80/18 fit the front?

Just concerned about the width.

Can get a set for $275 so cheap enough that if they are crap then no real loss.

I have a spare set of wheels and will just swap them to the bike if I think a ride might include a bit of dirt.

rosskko

Don't know about fit, but I think that Shinko was a Jap Yokahama brand or at least their technology. For $275 you can get a lot of k's. Euro brands are around $400-450 and for that much money you can get about 2 sets of rear and one of front in Shinkos! I think that you will be well in front. 

I general, the Net doesn't have bad things to say about them so it looks safe.

Have a look here. I get my tyres from them and the prices are great along with the service 4-5 days Utah to Stanthorpe Australia http://www.rockymountainatvmc.com/d/12/Motorcycle-Tires

Continental have dropped their prices (in the US, at least) to Shinko-level so if you have a look round you might find you'll save some serious dosh. The Road Attack 2 and the bis ply tyres they offer are some of the most underrated. They're worth a look. I use 'em (Road Attack 2 radials) on my K100RS back home.

ooohhh Rossko!  

Do I feel a rally coming on?

Michelin Pilot Active front tyre lasted on my K100 about 10 000km. I think that is relatively poor result.

Most I ever got out of bias ply tyres on my K100 was around 8500km, 10K is fairly good.

Climate, road surface material [tar and chippings, tar without the chippings, asphalt, concrete], ride style and whether you ride all year makes a difference. Over here we have cold and wet in winter and not much ice so we can ride all year. If you ride all year best to ask someone who rides all year where you live.

From what I see there are 2 or 3 tyres that seem to come well recommended for winter riding in our type of climate. I ended up with the BT45 on my K and love them in the wet and have found they feel at their best then. I was negative about them at first but having tried them am slow to change. Been through a lot of bad tyre types over the years and feel confident with them. Sensitive to correct tyre pressure.

My son put BT45 on his now old bike too and said they looked so old fashioned but he loved them. He brought a 'new' bike home last weekend, a VFR800 Vtec and insisted on a new set of PR3 or 4. He didn't get a choice because when I looked at the 'good' tyres on it they were years past their use by date and he had ridden home on back roads in an hour. You could have fried an egg on them when he got here. Basically he was told the keys are staying put until the new tyres come.

Oh dear - the OP certainly used the tin opener, didn't he? I'm in the Irish Avon RoadRider camp. Metzlers wear out far too quick (3000 miles per pair!!) and BT45s are now too expensive (Bridgestone want to get out of the big-bike crossply market and pushing the prices up is the only way they can do it - info from my tyre fitter). RoadRiders stick as well as the BT45s, are cheaper and I get better mileage out of them compared to the BT45s.

It would be interesting to see what we Eccentrics use because most if not all of us use the K all year. Us guys down here know that Comberjohn and Dai have better quality rad surfaces than we have but they sure clock up the k miles in all weathers.

Tyres have always been an emotive subject. Dai will remember the never ending debate between the Dunlop K70 Gold Seal, the Avon Roadrunner and the TT100. The only consensus was the Dunlop was rubbish. It came off the production line as a SQUARE tyre.... Back then BMWs didn't count. The K hadn't been invented and the rest came with Metzelers me thinks.

An idea for CF.....a poll on what tyres we use?

I got 10,000klm from my last Metzler Lasertec which I thought was OK but I wasn't happy with the performance. The BT45 on the front became badly scolloped with about 30% left and developed a very bad wobble going into a hard corner. I ditched it for a BT023 and put an Avon azaro on the back. Great combo. Azaro is at about 40-45% now with 5,000klm. If I can eek 10,000 out of it I'll be happy.
The BT023 and the Azaro I ordered from rockymountainatvmc.com

I was just reading through new product info and came across a new Metzeler tyre that's just available. They're called Sportec Klassik (Nuh, I didn't insert the end or beginning K) and are available in 100/90V18 or 110/80V18 for the front, and 130/90V17 or 140/80V17 for out back. Prices range from $187 front to $215 rear, at retail, but who pays that anymore!? Of course, online from the non-brick & mortar stores they'll likely be far less dosh. The jury's still out on what sort of mileage they'll get and how they'll handle, but possibly worth a go for those who wish to experiment.

These sizes are good for the K!

I use 110/90 on front and 140/80 rear but am still on Bridgestone BT45 as I have found them great for all year riding in what can be cold wet winter riding. I will happily take the K for a round day trip to Dublin [for me its 560km, 250km motorway each way plus a bit] even in heavy rain when maybe more sane people would park it and take the Kar but taking the bike allows me to use bus lanes and park under cover in an hour less travel time.

Both Ks came with Lasertec on them which were not out of date but they were like riding on cold grease in winter and no matter what I could never feel confidence on them.

KH mentioned the scalloping and I too had that but interestingly it hasn't happened on every BT45 I have had. One in particular and I now have a suspicion that it's not happening because I am running the front a little harder, about 38psi and feels very good. Either that or a slight change in manufacturing.

Other Eccentrics are using different tyres in our climate here and also finding them good so your own K and riding style can have an impact on what works for you.

To hijack this thread somewhat and add even more confusion, I have been reading that the 3.00-17 three spoke rear wheel can take a 150/70-17 tyre which opens up a whole new world of fancy radials. But looking at mine, the 130/90 is already very close to hitting the (1100) centre stand. But the 150/70 isn't as tall.. Can anyone confirm this really fits?

92KK 84WW Olaf wrote:
..........

KH mentioned the scalloping and I too had that but interestingly it hasn't happened on every BT45 I have had. One in particular and I now have a suspicion that it's not happening because I am running the front a little harder, about 38psi and feels very good. Either that or a slight change in manufacturing.

Hey Olaf. I think your suspicionnis right. Lower tyre pressures will cause scalloping in most tyres particularly bias plys due to flexing of the carcass placing greater stress on the leading edge of the tread pattern blocks. It's not just uneven wear. It's accelerated wear on that part of the tyre resulting in the tyre wearing out more quickly.