Running dissimilar tires

I'm getting ready to get a new front tire on my F8 and I was wondering what the consensus on running dissimilar tires front to back was. I put a Shinko 705 on the back but I wanted to run something a little softer with a more aggressive tread on the front. Had a guy basically tell me I was going to crash when I did it on my uly (and never did), but I don’t know if DS tires are the same way. Thanks. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

Kevin and Julia Saunders (Round the World adventurers) recommend a TKC80 front and a Tourance rear. My dealer refused to fit them.

I'm running Shinko 705's front and rear right now but wouldn't hesitate to put a 700 on front if I rode more off road. IMO matching tire profiles is relevant on a short wheel base, wide rear tire, aggressive steering geometry bike (crotch rocket) but not so much on an F8.

I assume you mean F800 GS. I put a TKC80 up front with an Anakee II rear about 600 miles ago after 8000 miles on my 800GS. Many folks here recommend such combos and there appears to be little risk...just the usual tradeoffs that we all make and often disagree about.

My experience has been that when on dirt the knobby front helps a bit and gives me a little more confidence. In mushy terrqin, it's a WHOLE lot better. On the road, it's about 10% louder and maybe the same incease in vibration versus street dual sports front and rear.

I ride 90% + on road, but when I do go off I really want my gear to gap my skills shortfall as much as possible and I think the knobby front, dual sport rear does it well, ride wise and spend wise. FWIW, my off road riding is pretty much hard packed flat dirt and gravel with occasional mud, clay etc.

I've been running TKC in the front and Shinko in the back for about 2 years, works great for me. I think it's a good combination of performance and price - handles well both on pavement and offroad, and doesn't cost me a fortune. A TKC lasts about 9,000 miles, and Shinko about 6,000 miles.

Great advice, thanks. The TKC sounds like its the way to go.

I run a Pirelli MT/90 front and Anakee2 rear. Works great front and back for the 70/30 road/dirt that I do. Been running different tires for 2 years and still here to tell abou it. I don't ride slow, ride long ways some days. Now on my trackbike no way would I risk it. Same brand front and rear. Different models ok but same rubber for sure. Dualsport different is good.

I ran a Tourance on the front and a Heidenau K60 on the rear to from San Diego to Prudhoe Bay and back with no trouble at all. It actually worked well on the Dalton in the rain.

He said BMW wouldn't allow them to fit unmatched tyres. May be a UK insurance thing.

I'm surprised to see so many people running TKCs on the front. I started with TKCs front and rear. The TKC on the front cupped out and had very erratic wear patterns and was wollowy at speed. I switched to a Heidineau front and the ride got much firmer on dirt and pavement. I kept the TKC on the rear but I'll probably switch after this one for something that wears a bit longer. I might try a Kenda big block or another Heidi on the rear.

Agreed. TKC's grip but wear out fast and faster. My pirelli front will last two anakee2 rears. Air down the anakee2 and it goes where I need it to.

Twice as long being how many miles?

I've been tempted to flip mine half way through. Might have to try that next time.

That`s what I do; have about 16,000Km on front of my 1100GS. TKC front, Heidenau rear, or M21 front, 606 rear are good combinations also.

The idea is that with dissimilar tires you could create a condition where one will stick better then the other. You reach a point speed in the corner where 1 might let go (slip) before the other. If both start to slip around the same G force the slide might be more controllable then if the front or rear slips first.

Some techs also frown about mixing Radial and Non Radial, but I am pretty sure our Front tire is bias ply and rear is radial from the factory. I don't think any 21" tires are made in radial configuration.

My TKC front is cupping, but I've cooked off a 606 and a Big Block (nice on slab)... Both rears lasted <> 3k
Primarily slab (weekdays) and a bunch of dirt on the weekends.
I like the flip the front tip. Why didn't I think of that before??
Another TKC in front and maybe I'll find a Heidi finally available for the rear.
First, a friend dropped off a Karoo from his Strom (didn't like dirt).

Mismatched on a DS is no problem IMHO, just work your way up to speed to get the feel.
S.

For a trackbike when you are pushing the tires AT THE TRACK sure I can see that. For a streetbike or dualsport bike while riding within reasonable pace for the street (read: speedlimit +/- a reasonable amount) I'd say not only is this scenario unlikely but if and when it happened the average rider would not have the skill to notice the slide or controll it in the way you are talking about.

I ride on the track a lot on my GSXR-750 trackbike and one end slides or the other. Very rarely do both slide AND when front or rear slides it is often a sign of:
worn tire
wrong tire pressure (too low or too high - usually too high on the track as tires gain heat
heat cycled tire (old and used for a few trackdays without tire warmers. Heat cycles of hot/cold, hot/cold galvanize the rubber and the tire becomes harder than intended).

These aren't typically problems on the street b/c riders are not using the tires past the intended use of a street tire. If you are on a dualsport on the street... well... then you pays your money and yous takes your chances. DS tires are not made to hang corners at 100+ mph all day like track tires.

Since taking up track riding I've learned a lot more about tires. The mfg's actually put more into the design, function and manufacturing of them than most people realize. They design them for an intended use and type of use. They will work in other applicaitons but as you see from the 3,000 mile wear out on many of the bigger blocked DS tires they wear out more quickly.

Once you take into account the probable use and application, riding conditions, wear and expectations you can pick a tire that will perform well for you in your own use.

Personally I am a huge fan of Pirelli tires. I would run the Pirelli Scorpio MT-90 front and rear if they made it in a 17" to fit the BMW. Until then I am riding the MT90 front and Anakee2 rear. They are good enough and similar enough compound for my intended use and type of riding.

I've run mismatched tires on my X Countries most of their lives. The bike's 19" front wheel severely limits choices up front, while out back, there are choices aplenty, thanks to the KLR.

Examples of matches/mismatches:

Front TKC-80 with
* TKC-80
* IRC GP 1
* Dunlop 606

Front Heidenau K60 with
* Kenda Trackmaster
* Dunlop 606
* Heidenau K60

Don't be afraid to experiment, but take it easy as you adapt to different combos.

For example, the Trackmaster is excellent for rocks and hardpack, but so-so on the highway. The 606 is excellent on the highway, but a little too hard for rocks. The IRC was good everywhere, and the rear Heidenau appears to be good nowhere -- but it matches the front!

This past weekend, I rode over one of the twistier and steeper hills in the neighborhood. It is also full of pot holes that the County filled with asphalt and packed down with the backside of a shovel.

The patch job probably lasted about as long as it took for the first car to pass. The road is now a combination of pot holes and loose asphalt and little rock mix.

I run a T63 front and a TKC rear, both normally pretty good on the street for a semi knobby tire.

This was all new to me and the first one I ran into was in a curve. The front slid into the pothole and added another ding to my growing collection in the front wheel.

May have happened with a TKC and no mishap occurred, but it dawned on me why dealers won't do it in our litigious society.

So I am removing my advice and you will have to form your own opinion.

Do you know the road and ride it often?
Were you riding at the speed limit or reasonably close to it?
Did you see gravel on the road or is it usual to have it there? Possible to have it there?
Did they have a sign recently about the roadwork?

All of these questions lead into whether it was reasonable to ride the bike at the speed you were on that road on the day in question. I'd imagine all are more related than disimilar tires. Sounds like any tire other than a knobby would have had some issues with that road.

Oh and did you clean out your shorts after? Sounds like a not-fun moment.