Morning,

Bought my 1988 bike from an old fella who had owned it almost from new, came with old worn Bridgestone BT45's fitted. Handling is interesting. Any recommendations for replacements? I will not cover a lot of miles, I tend to potter around most of the time riding solo.

Many thanks

Andrew

There's not a huge range of options for the Y-spoked wheels unfortunately. The BT45 were standard on the K100 and they're still a very good tyre, well suited to the K. Quite a few members here use them. Unless you intend to crank your machine over thru a few fast bends, I'd suggest sticking with them. You can go a size bigger than what's stated in the Rider's Guide if you want. Slightly improved handling and maybe a little safer due to a slightly bigger contact patch. You'll want to run them around 38-40 psi (cold) and 3 less in the front.
If you're experiencing some handling issues it could be due to hardened rubber if they're old or they could simply be worn out. There's a manufacturer's code on the side which will tell you how old they are.

I've only ever run the Metzelers on my K100's , annual mileage was usually around 7000km , and were replaced every 2nd rego check . 
I would say they were good for 10,000 to 12.000km of easy riding. 
How do they compare to the BT's , mainly the compound and handling .

Avon RoadRiders. They're as good as BT45s and last longer.

I have a Michelin Pilot Activ on the front that I've been quite impressed by, and they're cheap to boot. But then I quite like Conti Go!s and didn't think much to a Roadrider so my taste in tyres is apparently all wrong..

Since someone mentioned Metzeler I'll also say that I currently have a Klassik on the rear and am finding it difficult to recommend in any way. Hard compound, a very harsh ride, squirmy in the wet/damp and surprisingly quick wear. Like, ~4500 miles surprising.

I had BT45s on my '85RT when I bought it. Quite happy with them.
Replaced them with Pirelli Sport Demon, mainly because some here have been pleased with them, and to try something different first hand. I've been very happy with them, too.

The BT45 has a harder compound in the centre of the tread, so will last longer if you do a lot of motorway riding with less lean. Less likely to develop a flat area in the middle of the tread. I recommended them for a friend on his Honda CX500, as he is a very conservative rider, so no hard leaning or cornering.

My only experience of Avon was in 1973, when they were a massive improvement on the OE Yokohama on my little Honda. Likely of no relevance today! Zero experience of the Metzeler.

Bill

Thanks guys thats really helpful, will probably stick with the BT45's

I have BT45s on the RT and have been sticking with them as they are hard to beat. Current set I got at end of October last, 110/90/18 front and 140/80/17 rear. They are coming up to 5,000 miles on them now and excellent in all conditions from -6c at one point to lots of rain. I run 38-40psi in front and 42-45psi in the rear. Anything less and the handling feels very discouraging.

They are worth shopping around for, I got some wide variation in prices last October. I paid €245 ride in the bike as opposed to simply dropping off the wheels so I cant complain.

ush1000 wrote:Thanks guys thats really helpful, will probably stick with the BT45's

make sure you maintain a decent pressure on those. If the pressure drops too much you can get bad scolloping on the front tyre. It has a block pattern which can promote uneven wear. Could explain the "interesting" handling you have on the old ones now.

I've been running a shinko @38psi on front, and a BT45 on rear @ 42psi.
The ride feels tight and sure!  When I replaced the old square BT45 with a new one the turn-in and roll-over became so much better on corners.

Dale S wrote:..... When I replaced the old square BT45 with a new one the turn-in and roll-over became so much better on corners.

That would be because the BT45's design features a nicely rounded crown which gives a nice smooth roll-over (tip-in) and helps to give a nice confident feeling to the handling. The big failing of the BT45 imo is the front tread pattern. That block pattern is sh!t. The rubber flexes more under stress and then quickly wears unevenly, destabilising the front.
Dale, your idea of pairing the the BT45 rear with a Shinko on the front is probably a good idea. Can you post details?

I've settled for the Pirrelli Sport Demon front and back for my K100s. Can't fault them. They're a single compound bias ply and not really suited to a lot of straight highway running.

The BT45 on the front was an interesting one but am very happy with it.

I had Lasertecs on both Ks and found them terrible in our climate.

The BT45s were a great improvement. I now change front and rear together. The front needs to be kept up to 38psi to reduce or avoid scalloping but it does inevitably happen. Keeping the pressure up I now figure forces the tyre to run on and wear the centre harder compound when the bike is upright, rather than sitting down a little and wearing the softer side compound. I get about 12,000 miles on the rear [which I keep at minimum 42psi] and the front is more than excellent up to that mileage. I am happy with that and to replace both tyres together. I did keep fronts a bit longer but after the rear was changed the scalloping on the front increased to the point where I didn't like the front. My current set was put on at end of October and I expect they will be replaced before the summer

Dai rides all year here in the same climate, so does 88, BAE, Sidecar Paul and a few more and our climate is much the same as UK. I think they use different tyres but at least its the same riding conditions.

What has amazed me is the difference in a bad tyre seems not so noticeable if you are riding about 10-12C but its very noticeable under 5C. I suspect about 15-20C any tyre is probably good especially harder ones.

Holister wrote:

Dale S wrote:..... When I replaced the old square BT45 with a new one the turn-in and roll-over became so much better on corners.

That would be because the BT45's design features a nicely rounded crown which gives a nice smooth roll-over (tip-in) and helps to give a nice confident feeling to the handling. The big failing of the BT45 imo is the front tread pattern. That block pattern is sh!t. The rubber flexes more under stress and then quickly wears unevenly, destabilising the front.
Dale, your idea of pairing the the BT45 rear with a Shinko on the front is probably a good idea. Can you post details?

I've settled for the Pirrelli Sport Demon front and back for my K100s. Can't fault them. They're a single compound bias ply and not really suited to a lot of straight highway running.

I put the Shinko 712 100/90/18 on at 74,300 miles a couple of years ago to replace an aging chen shin Hi-Max that actually was not too bad of a tire for the money. Now at 84,100 miles the Shinko has about two thousand miles left in it, give or take. It has been a good tire over mixed highway and my favorite twisties. Seems to compliment the BT45 rear just fine for my riding style which is anywhere from "Old Man" to slightly Adventurous!!
"Big Red" is good at over 100mph and like I said rolls-over, down and up nicely!  It is starting to show a little more wear on the left side due to the crown on the roads here. Not much tramlining/groove following that would lead to concern. I'll be getting another one when the time comes..

Hi guys, as an update I have been given (freebie) a part worn pair of tyres, probably enough tread to last me a year with the amount of riding I do.

Thing is the front is a Metzeler ME330 and the rear is a Lasertec. What do you reckon, ok to use em?

Andrew

ush1000 wrote:Thing is the front is a Metzeler ME330 and the rear is a Lasertec. What do you reckon, ok to use em?

If they meet any one of the following conditions—are older than five years, have cracks or checks in the rubber, or have shallow tread depth—I wouldn't use them. A lot depends on your degree of desperation and your style of riding. The age code is a framed four-digit number below the midline of the sidewall. The first two numbers are the week of manufacture; the second two are the year.

If the tires are in good condition, many riders mix tires types with acceptable results.

Hello!

Older than five years and I wouldn't use them, they'll be slipping in rain but last forever because the rubber is hard as wood.

Bridgestone BT 110/140 is a well known good tire!

Mixing Tires isn't a good idea, except you know what you are doing.
Good tires make a big difference in riding a bike.

Cheers

Thanks guys, those tyres will be going in the bin, too old. Thought I could save myself a few quid as I have had loads of bills to pay recently, need to work some overtime!

Another quick question regarding tyre sizes, seems you can use different sizes on the K100RT, my existing tyres are 100/90 18 and 130/90 17. The Metzelers were 110/80 18 and 140/80 17.

Both sets fit the bike but which is best..........is this a can of worms? My riding is very safe, slow and normally solo. Mixture of country lanes and dual c'way. The strange handling at the moment I am fairly sure is entirely down to the fact that the existing tyres are old and worn. I like the idea of larger tyres as they have a larger contact patch and they look better (well the 180 looks great on my old Ducati!!).

I'd use 'em, but I'm a little bit wurr, little bit weee, little bit swoosh-swoosh-swoosh.

Are you a geezer?  EDIT: Guess not

140/80 is allowed, the handbook says so, and many people seem to prefer it over the 130/90. 110/80 as a front is gaining popularity because you can get modern radials in that size, and again people seem to like them. Certainly the 100/90 looks very skinny!

If you think that fitting bigger tyres for a bigger contact patch is just all gain then think again. A bigger contact patch with the same load on the bike will make aquaplaning easier. There is no point in going bigger unless it gives you access to better tyre technology. 
A bigger tyre also weighs more making the bike slower to respond to cornering, not that many people would notice on a K.

What BobT says. From experience I know that even going from a 130 to a 140 (only size available at the time) introduces a whole new wrestling match at the rear. In the end I "solved" the problem by going from the recommended solo pressure of 38psi to 40psi. It doesn't seem like much but what a difference in the handling!

It's tire time for my 85 RT so I'm thinking 140 and 110 for Michelin Pilot Active.
http://www.ebay.com/itm/Michelin-Pilot-Activ-Front-Rear-Tire-Set-110-80-18-140-80-17-18475-20811-/311652249753?hash=item488febf099:g:7iEAAOSw65FXsOrP&vxp=mtr

Will this slow the steering down too much?  I don't want to turn it into a barge.

SteveFord wrote:It's tire time for my 85 RT so I'm thinking 140 and 110 for Michelin Pilot Active.
http://www.ebay.com/itm/Michelin-Pilot-Activ-Front-Rear-Tire-Set-110-80-18-140-80-17-18475-20811-/311652249753?hash=item488febf099:g:7iEAAOSw65FXsOrP&vxp=mtr

Will this slow the steering down too much?  I don't want to turn it into a barge.

Turn it into a barge? You mean you have not noticed that the K is a barge. 
You will never turn it into a Ducati though.

BobT wrote:Turn it into a barge? You mean you have not noticed that the K is a barge.

Oh!  Blasphemer!! Wash your mouth out and go sit in the corner.

Steve. You'll find those tyres a bit cheaper HERE. And I think they have free freight in the States.
There are quite a few here who use the wider tyres. IMO I don't think you'll be disappointed.

Holister wrote:

BobT wrote:Turn it into a barge? You mean you have not noticed that the K is a barge.

Oh!  Blasphemer!! Wash your mouth out and go sit in the corner.

Steve. You'll find those tyres a bit cheaper HERE. And I think they have free freight in the States.
There are quite a few here who use the wider tyres. IMO I don't think you'll be disappointed.

Sorry chap, I took my blinkers off when I owned other bikes as well as the K.

Thanks!
Been beating on the old thing a bit today and fitted up some stainless brake lines; the previous owner wore the rear pads right down to the metal backing!

This bike is going to be a bit of a work in progress as it needs a LOT of stuff to be ready for the road.

Wrong thread:-)

Chocolate wrote:Wrong thread tread:-)

Fixed that for you there......

92KK 84WW Olaf wrote:

Chocolate wrote:Wrong thread tread:-)

Fixed that for you there......

What would I do without you Olaf