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ROGSLATER
04-13-2009, 04:58 PM
I realise there are piles of stuff here on Tyres but I can't find anything to address my question.
My 05 R1200RT does not have nutral steering. It over steers considerably, IE the front wheel falls into turns causing me to apply opposite pressure until the bike is back upright. On a twisty road this becomes really tiring, it really is hard work.
It is such a relief to have a local ride out on any of my fifties and early sixties Brit singles just to realise what effortless nutral steering is all about. Any of these can be steered hands off the bars, it only requires light pressure with the knee.
The RT has the original Michelin Pilot Power's with 6000 miles on them. Raising front pressure to 40psi does help but by then the ride is getting real hard but it leads me to suspect that a different tyre make or profile may cure the problem. I am even considering trying a narrower rear. Any one out there with any experiance with this problem and a possible solution???

Thanks
The geriatric on the Frontier

Semper_Fi
04-13-2009, 05:20 PM
you may want to see if your tires are squared off....

My RT handles beautifully, does not fall into corners and i can adjust mid-corner if needed.

deilenberger
04-13-2009, 06:22 PM
+1

Something is seriously wrong. Certainly a squared off tire can cause a "over-center" sort of feeling as the lean increases past the corner on the tire, and it might feel like the bike falls into the turn.

Other things I can think of - have you done any suspension modification or tuning? If the rear of the bike is higher than designed with the rider on it - the bike will tend to turn-in faster.

cookie
04-13-2009, 07:09 PM
I agree with Don, it would make sense as you approach the ridge on the worn tire there would be bit of a dive. My experience at 6ooo miles you need tires anyway. I assume there is some chopping on the left side of the tire?
My Rt is the most stable nimble bike I have ever enjoyed owning.
my 2 cents.

leadfoot
04-13-2009, 08:08 PM
10K on my RT, with cupping right an left of center on my front, and squaring on my rear. Both are Z6 tires, and they have begun to exhibit a "mudgrip" sound with the wear. . I do a lot of straight line riding, and have noticed that turns are more effort now than when new. I used to roll it into a turn, now I stear it. I attribute this to the shape of the tires. I agree with previous posts, take a good look at the tires, and you may find your problem.

47512
04-14-2009, 12:51 AM
Make shure you have the correct air pressure in the tires, there is alot of weight on the front tire of a RT.

I have a friend with a Yamaha FJR that had the same issue with turn in, more air pressure pretty much solved the probblem. The tires were Bridgestone BT021's

Metzler Z6's on my R12R very nutral steering.

Air is not going to help worn tires, it may be time.

Ken G.

BernieEcht
04-14-2009, 12:57 AM
I had a similar problem, and solved it by lowering the air pressure to the recommended tire pressure.
You may have to adjust your spring preload on your rear shock. Your front end maybe getting a little light, if the rear end sags to much.

ROGSLATER
04-15-2009, 02:05 AM
Thanks fellas for the ideas, here a few details on points raised.
Bike over steared a little when new, gradually got worse.
Front tyre is still as round as new, rear has more wear in center than sides but I would not yet describe it as squared off as in brick shape.
No mods at all to the bike in any way.
I only ride solo, problem much worse on recomended tyre presures. 40 front and 45 rear helps, but it rides like a buck board.
ESA rear load in middle or highest position also helps, (steeper head rake.) but then I cant touch the ground.
Full fuel tank makes it worse, logical on a bike that is already top heavy by design.
My close on 60 years riding experiance sugests to me the rear tyre is too wide, made worse as the center comences to wear. Just out of curiosity I intend to tackle the rear tyre first with the roundest I can find then try a narrower one just to see the result. Thanks again for all the sugestions.

The geriatric.

kbasa
04-15-2009, 03:33 AM
You need tires. If it feels like you have to push it into the corner and then it falls in, that's you pushing your bike over the edge of the square section.

I get about 6K out of a rear.

I went to the new Conti Road Attacks and they're amazingly neutral. Try them next time.

WDaigle
04-15-2009, 07:24 PM
Try Michelin Pilot Road IIs. I switched to them on my last tire change on an 06 RT. I have over 12,000 miles on them now with no cupping or flat spots and plenty of rubber left. I do a lot of straight up riding, not a lot of twisties in Louisiana. I also switched to DynaBeads for balancing. My bike has never exibited any problems with steering except for minor falloff with other tires that had flat spots or severe cupping. I always ride with the recommended tire pressure. You may have other more serious problems than tires.

Semper_Fi
04-15-2009, 07:48 PM
+1 on the Pilot 2's i have those also - everything Gator said, plus i would add they are very very good in the rain.

WDaigle
04-15-2009, 08:05 PM
+1 on the Pilot 2's i have those also - everything Gator said, plus i would add they are very very good in the rain.

+1, an excellent tire in the rain. As far as your problem, you may want to check your ESA. I had a problem with mine when the bike was new. The pre-load setting was stuck on the one-up setting. This happened when I was in Vermont at the MOA rally in 06. I had to ride home with it on that setting with all of my camping gear, etc. It took a while to diagnose and correct the problem. Untill then when ever I rode two-up the bike did handle differently although I really did not ride many twisties during that time. Short story-the ESA was not adjusting the pre-load all of the way up or down when the bike was new(defective shock & ZFE) After it was fixed it handled even better than it did when it was brand new.

Tom K.
04-15-2009, 09:06 PM
+1, an excellent tire in the rain. As far as your problem, you may want to check your ESA. I had a problem with mine when the bike was new. The pre-load setting was stuck on the one-up setting. This happened when I was in Vermont at the MOA rally in 06. I had to ride home with it on that setting with all of my camping gear, etc. It took a while to diagnose and correct the problem. Untill then when ever I rode two-up the bike did handle differently although I really did not ride many twisties during that time. Short story-the ESA was not adjusting the pre-load all of the way up or down when the bike was new(defective shock & ZFE) After it was fixed it handled even better than it did when it was brand new.

The way to check for a stuck pre-load is to make certain the dash icon starts flashing about 5 seconds after the new setting is selected. Also, at this time the rear of the bike should rise or fall accordingly. When mine stuck in the 2 up position, BMW's solution was to replace the rear shock under warranty.

I keep the preload in the position suitable for the load (solo, luggage or two-up) and have never felt any oversteer. Due to the telelever, the different road feedback took some getting used to but my RT has always had neutral steering.
Tom

RACEYDOG
04-17-2009, 05:44 AM
Aren't Pilot Power tires more for sport bikes and not sport touring bikes? I have Pilot Road 2 tires and they are excellent. The Pilot Power tires are reeeeeaaalllly grippy. Maybe too grippy for such a heavy bike? Could it be that it makes your bike squirrley? Are the tire sizes similar to Manufacturer specs? Are both tires similar models? What air pressure are you using? I use 40psi/42psi.

Just my .02

RACEYDOG
04-17-2009, 05:46 AM
Oh yeah. Dyna Beads work great.

ROGSLATER
04-26-2009, 02:51 AM
[QUOTE=Rogslater;446548]I realise there are piles of stuff here on Tyres but I can't find anything to address my question.
My 05 R1200RT does not have nutral steering. It over steers considerably, IE the front wheel falls into turns causing me to apply opposite pressure until the bike is back upright. On a twisty road this becomes really tiring, it really is hard work.
It is such a relief to have a local ride out on any of my fifties and early sixties Brit singles just to realise what effortless nutral steering is all about. Any of these can be steered hands off the bars, it only requires light pressure with the knee.
The RT has the original Michelin Pilot Power's with 6000 miles on them. Raising front pressure to 40psi does help but by then the ride is getting real hard but it leads me to suspect that a different tyre make or profile may cure the problem. I am even considering trying a narrower rear. Any one out there with any experiance with this problem and a possible solution???

Thanks
The geriatric on the Frontier

Update
I misnamed, the original tyres were Pilot Road. Problem now completly cured, this is how.
From new I found the bike to require some muscle on twisty roads and it oversteered mildly. Both problems deterioted as the tyres wore to the point that it was real hard work compared to my old Brit bikes. I assumed it was normal on the RT due to weight and it's top heavy design.
I realise that the tyres were due for replacement but to fit the same equipement would only put it back to a repeat situation.
Convinced the rear tyre size was most of the problem, I fitted a Pilot Road 2 170/60 instead of the original 180/55.
The difference was most dramatic. Effort required to change direction was a huge improvement. At cornering speeds over 50mph with power applied I was able to loose the bars due to perfectly nutral steering. At lower cornering speeds there remained a very small amount of over steer requiring slight counter steer pressure
Next I fitted a new standard size 120/70 Pilot Road 2. front This resulted in a further modest lightening of the steering and completly eliminated what remained of the oversteer. I put pressures at the BM recomended 32 fnt 36 rear.
Michelin specify a 5.5" to 6" rim for the 170 section tyre, with the higher 60 ratio, the fitted tyre is rounder than the 180/55. The duel compound design of the series 2 tyres will assist in maintaining this shape as the miles go up. To put iceing on the cake the 6mm increase in diameter results in the speedo being dead accurate instead of the 2mph fast with the 180/55 tyre. The handling is now definitely superior than when new, I would say 90% of the problems were due to the over size rear. The other 10% was simply center wear on the front.
With my in excess of fifty years motorcycle experiance i submit that it does not take a rocket scentist to realise many modern motorcycles are over endowed with form over function. This is particularly true of tyre sizes, they get bigger and bigger just for the sake of style and testorone.
I am a most happy geriatric on the frontier. See yarl at the International rally

nplenzick
04-26-2009, 11:32 AM
This is very interesting. Do you know if running the smaller tire decreases the load capacity of the bike?

indycar
04-26-2009, 02:00 PM
[QUOTE=Rogslater;446548]With my in excess of fifty years motorcycle experiance i submit that it does not take a rocket scentist to realise many modern motorcycles are over endowed with form over function. This is particularly true of tyre sizes, they get bigger and bigger just for the sake of style and testorone.


well, I'm happy you're happy and satisfied. Despite all the feedback you received here, you never wavered from your origional notion of a solution. Which is fine and your option for sure. But by all indications - you're solving a problem that should not exist. This is the first concern I've read about the RT oversteering, and it seems the same for the other posters. Changing tire sizes of course alters handling. Me wonders if now you're not masking the real problem

I think testosterone has little to do with BMW's selection of tire size.

ROGSLATER
04-26-2009, 04:15 PM
This is very interesting. Do you know if running the smaller tire decreases the load capacity of the bike?

Yes, Michelin have the load capacity on the 170 and 180 tyres at 783 and 805 lbs respectivly. Hardly a consideration in practice.

ROGSLATER
04-26-2009, 05:00 PM
[QUOTE=Rogslater;450797]

well, I'm happy you're happy and satisfied. Despite all the feedback you received here, you never wavered from your origional notion of a solution. Which is fine and your option for sure. But by all indications - you're solving a problem that should not exist. This is the first concern I've read about the RT oversteering, and it seems the same for the other posters. Changing tire sizes of course alters handling. Me wonders if now you're not masking the real problem

I think testosterone has little to do with BMW's selection of tire size.

Perhaps my long experiance with smaller lighter bikes makes me more aware and critical of big heavy modern bikes steering characteristics. The 1200RT is my first modern bike and I love it. It was the excellent feed back from fellow members who bought me up to speed on modern tyre wear situation. In my inexperiance of the new technology I was not aware that my tyres required changing at such low miles compared to what I am used to. The issue was changing shape not lack of tread.
However, I am not alone with my view that tyres are getting far to big for no better reason than "ape the racer" marketing. Professinal road testers often blame over size tyres on "slow" steering. Several very experianced road riders share the same view as do engineers not conected to marketing.
I realise I am in my own little time warp but my RT1200 with the slightly narrower rear tyre is now a much lighter handling bike than it ever was.
Thanks fellars for the input and advice.

deilenberger
04-26-2009, 09:47 PM
Roger? (I think..)

If you can clear this up for me..

Besides changing the rear tire profile, you also changed tire models from Pilot Roads to Pilot Road-IIs?

I'm glad your problem is solved, but I suspect you might have accomplished the same by simply changing the tire model. It's always amazing how much better the bike feels with fresh tires on it even when they're identical to the ones you took off.. and the new PR-II's are a very neutral feeling tire, took me a day or so to get used to them actually. I was used to my Conti Road-Attacks which had about 12,000 miles on them needing a firm push to initiate a turn, then some control to keep the turn from becoming an undesired decreasing radius one.

See you at the National!

ROGSLATER
04-28-2009, 12:56 AM
Roger? (I think..)

If you can clear this up for me..

Besides changing the rear tire profile, you also changed tire models from Pilot Roads to Pilot Road-IIs?

I'm glad your problem is solved, but I suspect you might have accomplished the same by simply changing the tire model. It's always amazing how much better the bike feels with fresh tires on it even when they're identical to the ones you took off.. and the new PR-II's are a very neutral feeling tire, took me a day or so to get used to them actually. I was used to my Conti Road-Attacks which had about 12,000 miles on them needing a firm push to initiate a turn, then some control to keep the turn from becoming an undesired decreasing radius one.

See you at the National!

Hello Don
Yes, with out a doubt the same improvements would come from the standard ROAD tyre with the 170/60 profile. However I went with the ROAD 2 because of the duel rubber compound. This feature should cure the problem of the profile going off. I found the 180/55 was not a nutral steerer from new, it got progressivly worse as the profile flattened out. The front also suffered this problem but its adverse effect on steering was minor compared to the rear. The profile of the rear after a few thousand is so flat and wide that only a few degrees of lean places the contact patch well off the chasis center line.
It does follow however that a rear standard ROAD in the 170/60 profile will not deteriate so fast as the 180 simply because it is inherently much rounder profile to start with.
My digs at the rally 16, 17th is the Hotel Elizabethan in Elizabethton. Nicely out in the boonies for peace and quiet and half the cost of Johnson City, $55 geriatric rate.
423 542 4466

Roger Slater

kbasa
04-28-2009, 02:28 AM
The other 10% was simply center wear on the front.
With my in excess of fifty years motorcycle experiance i submit that it does not take a rocket scentist to realise many modern motorcycles are over endowed with form over function. This is particularly true of tyre sizes, they get bigger and bigger just for the sake of style and testorone.
I am a most happy geriatric on the frontier. See yarl at the International rally

I have to disagree. When you're feeding 110hp and 85ft lbs of torque through a tire, a narrow tire isn't going to last long nor is it going to deal well with applying that torque coming off an apex.

I use the whole tire, edge to edge. I shudder to think what would happen if I went with something narrower.

ROGSLATER
04-29-2009, 03:37 AM
I have to disagree. When you're feeding 110hp and 85ft lbs of torque through a tire, a narrow tire isn't going to last long nor is it going to deal well with applying that torque coming off an apex.

I use the whole tire, edge to edge. I shudder to think what would happen if I went with something narrower.

Dave, I agree with you entirly but I am not road racing, I am touring. I can't imagine useing the bikes 110 BHP on a public speed controled highway with the pegs scraping. That would be over 100 in forth and 135 mark in 6th.
From a technical piont of view the 170/60 is not a "narrow" tyre, it is a little narrower and a tad taller than the 180.55. Its more rounded profile actually has more footprint leaned over than the brick shape 180 I have just removed. Agreed, footprint is bigger on a NEW 180 but in my experiance it changed profile very quickly.
Michelin's (72W) load and speed rating of the 170 tyre is far higher than the bikes weight and speed capability. I understand the 170/60 is correct spec tyre for the heavier 1150 Oilhead models.
I am optimistic the two compound technology will result in far higher mileage than the single compound tyre even at the slightly smaller section and for certain I find the bike is less tiring or is it tyreing? than with the 180 tyre.
It is a most interesting subject, I will keep a eye on it and report back as to how it goes. You may be intersted in having a look at "Motorcycle Handling & Chassis Design" by Tony Foale. It is a very highly regarded industry referance work. It can be viewed on line.

Roger

dtpetty
05-23-2009, 09:42 AM
Thanks fellas for the ideas, here a few details on points raised.
Bike over steared a little when new, gradually got worse.
Front tyre is still as round as new, rear has more wear in center than sides but I would not yet describe it as squared off as in brick shape.
No mods at all to the bike in any way.
...

The geriatric.

Wow! I am very surprised to hear about steering (I guess I always call it cornering on a bike) issues on a 1200RT. I have the Dunlop Sportmax that came on my 1150 RT-P. These are the run-flat rated police tires that CHP uses. They are great! Absolutely positively neutral with the nominal recomended suspension setting, (there is a "police" strut in front).

This is the best handling bike I have ever ridden or can imagine ever riding. Effortless heaven on 2 wheels!

Dean
'04 1150 RT-P

STAN
05-26-2009, 02:00 PM
I find this thread fascinating. I just put on a new Avon Storm on the rear, and I'm back in riding heaven. I tolerated a flattened off rear for about 1000 mi. longer than I should have. New sneakers always feel great. I'm back to neutral steering.
I sure don't discount the idea of going to a tire with a slightly different profile, especially if it slows down the "flattening effect". Load capacity should not be a problem as my touring is always one up, and in 24,000 mi. I don't think I have ever come close to using all of the 100 plus HP. I'm not real fast, but I'm no slouch. By the way, I run 40/42. Less than 38 in the front leads to cupping real fast for me.

wezul
05-26-2009, 02:17 PM
I had about 9600 miles on my original Bridgestone Battleax's when they were replaced with Metzeler Z6's. What a difference.
I thought it was the rider (me) who was fighting the bike through the turns, especially as the tires got more miles on them. I didn't even give the tires a thought, I believed that it was the rider's (me) lack of experience.
The rear was definitely squared off when it was replaced and now, after reading this thread front to back, I understand about the feeling of "falling in to" a turn.

This is another reason why I like this club and this forum. Information is power.

Thanks guys!

ROGSLATER
10-14-2009, 07:04 PM
I have to disagree. When you're feeding 110hp and 85ft lbs of torque through a tire, a narrow tire isn't going to last long nor is it going to deal well with applying that torque coming off an apex.

I use the whole tire, edge to edge. I shudder to think what would happen if I went with something narrower.

Hello Dave
I promised to get back with a update on my tyre choice.
The pair of new tyres have now covered 11,200 miles. I am delighted to report that the 1200RT, STILL STEERS PERFECTLY. The replacements are Michelin Pilot 2 duel compounds front and rear. Front size is standard spec 120/70. Rear is my chosen slightly smaller section, higher profile 170/60. It is the rear that has cured the problem of substantial over steer on the original Michelin single compound 180/55 tyre as it wore. The bike can still be steered hands free and it looks like both tyres still have at least 5000 miles to go. Rear has lost only a little of its original profile, the orginal tyre had lost most of its round profile at only 6000 miles which put the cornering contact patch well off the chassis center line. The front has developed a couple of minor ridges where the compounds change and is now sensative to tyre pressure. I can feel at once if the pressure is a couple of LBS down. Very pleased with the mileage and steering of the new tyres which have already covered almost double the miles of the originals.

Roger

RTRyder
10-14-2009, 10:46 PM
Being well versed in the handling of British machines in general, and the old thumpers in particular, plus owning an RT, I have to wonder if in fact there is something wrong with yours and the tire profile change is just masking the issue as others have suggested.

Granted, my RT doesn't come close to being as nimble as my ES2 Norton, but it doesn't exhibit any of the characteristics you describe in yours and I'm still on the factory tires starting to show signficant wear, they are soon to be replaced with a set of Avon Storms.

I did find the handling of the RT to be sub par with the stock suspension (non ESA), but a swap to a set of Ohlins cured that problem, it tracks true through corners and the turn in is smooth with no hint of oversteer, nor does it require any noticeable effort to initiate or hold the line in a turn.

Though the RT is a much larger machine I think it handles very similar to my 850 Norton, even if it does have radial tires with a far greater contact patch than the K81s the Norton wears. Just my observations...