For any traveler out there this is a grave WARNING.

DO NOT EXEED SPEEDS of 130Km/h when riding with Michelin DESERT tires on TAR.

You are almost certian to have the bike go into a slow oscillation that will progresively get worse and if you do not drop your speed it will eventually lead to an accedent.

The problem is that sometimes there is now warning oscillation and you could push the speed to as much as 155km/h and if the wobble start at this speed there is no stopping it, you will almost certainly come off.

If anyone has had experiance with these tires I would like to know more.

you're being alarmist!! you don't even tell us what you were riding.

it depends on many other factors including the bike and luggage, but, not least, the rider. I had an XT that wobbled on T63 at that speed and it was best left alone - the more I tried to control it, the worse it got and that may well be the problem with you on your bike.

also, what are you doing thrashing your poor bike? chill out and enjoy the view

The bike is a BMW HPN Paris Dakar with big bore high compression motor producing around 70 hp. At 140km this bike is not even breaking a sweat. The load at the time of the accendent was very heavy (loaded for a cross Africa trip with an extra set of tires on the back.
The weight was not an issue as the swaying arround appeared even if the bike was not loaded.
I cannot stress this fact enough as currently my client for whom the bike was build is currently in hospital with 5 broken ribs and a broken colar bone as well as a punctured lung from the broken ribs.

I have driven this bike on a lot of occations myself and this is a problem that we both experienced, only differance is that he came of and not me.
Someting else, is the fact that the rake angle of the bike was changed to give beter in line stability at high speeds as well as the fact that the swing was longer by 100mm to further improve inline stability.
Check www.hpn.de to see more on the frame changes and other developments by HPN.

I hope your client gets well soon.

I remember John Deacon reckoned he got 192kmh off road on his Dakar bike which is, I gather, pretty similar to the HP2. I don't think he blamed the bike for his crash ... he hit a tree stump, as I recall.

for anyone else considering Deserts, I'd say to keep it in perspective as loads of overlanders have done millions of kilometres on these fantastic tyres.

The knobby tires aren't made for these speeds! Especially the tube-type like Deserts. Tube-type run much hotter than tubless.

I had my "H" rated tubless Heidenau K60 wrekked in Middle East driving long term around 160kph two up full of luggage on mountain roads lot of accelerating and engine braking and there were some loger parts to take up higher speeds (R1100GS doesn't give any sweat there as well - normal running rpms and proper "cruising speed" for oilhead boxer) in more than 40 degrees celsius heat so the rear tire took it's abuse and the tire just cracked and throw away some knobbies and rubber parts laving me running on textile on some parts of tire - it overheated! Had to drive around 2000 kilometres on textile back to civilized Turkey to get new tire on slow speed, but amazingly no punctures altough i had to do lot of gravel roads - very thick and strong layer of textile the Heidenaus have via my practice.

On medium or colder weather here in Europe on autobahn they're OK running high speeds on loger term - they're "H" rated afterall.

For any knobby tire i think more than 130-140kph can turn fatal in more hot weather, especially driving with lot of loaded mass (luggage). But you rarely need these speeds on travelling! The power is good for fast overtankings, crossing corrugated parts of the road etc etc more security, but it's just temporarely taking up to higher speeds that the tire can cool down again.

The BMW R900RR (HP2 precessor) the John Deacon and Jimmy Lewis drived had serious problems with their tires on that race - they melted often under huge horsepower/torque in Dakar rallye conditions even on soft sand bits - and their "comfortible cruising speed" for 900cc racing-tuned boxers were around 190kph (that's offroad!) indeed. To fight agains those problems Mezeler has developed new version of Karoo tires for high performance offroad twin-cylinder machines (i think they should be stock spec for the HP2), hopefully they can resist that much power output on offroad... They're maybe worth trying out for travellers who want to drive fast on some tarmac legs but need knobby tires on other parts of the travel - if they're good enough for 2-cyl offroad racing then they're certanly good enough for (fast) adventure travelling i guess.

Margus

[This message has been edited by Margus (edited 21 January 2006).]

That is because DESERT front tyre pattern which is designed for pure offroading and just satisfying grip on tarmac. Do yourself a favour and fit front T63, rear Desert - result is much better onroad, just slightly worse offroad but still pure offroad combination. I use T63 for a several years, fantastic onroad and very good offroad, no problems at higher speed ( single, max. is around 165 km/h )at all, and VERY good grip on wet tarmac surface.
Regards,
AnteK, XTZ 660

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AnteK

Obe Kinobe says that when you hold hand over licking flame you should pull hand away not put inside. Obe Kinobe says when get big wobbles on bike do not try to go faster. Obe Kinobe says sailor who gets drunk and falls off ship is taking part in evolutionary process. Obe Kinobe says many posts same story.

http://www.horizonsunlimited.com/ubb...ML/000259.html

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I had survival training but couldn't use a petrol bowser, let alone ride a bike. Claudio! Claudio!

Michelin said that the speed rating of the Desert's is R meaning up to 170km/h on tarmac. They had no specific speed rating for offroad use.
I need to make one thing very clear, the Michelin Deserts are the best tires for offroad use they have a high ply rating, can carry really heavy weight and will not come apart no matter what you put them through. And on top of this they grip like hell in the loose stuff.
What was quite amazing was that the impact of the accident sheered of most of the spokes on the rear wheel but the tyre was still fully inflated with no damage to the rear rim.
The problem is just simply that they do not like to be driven fast on the tarmac!!!

ever seen deserts after the Finke race in Oz? those loons do 200kmh on them and the blocks tear off even though the carcass stays together

Quit puttin 40 in your tires.
HHAAAAARRRRRR!!!!!
Rod,,,,been there