eye opening - tyres on GSA - just WOW !

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just got a new bike - an air cooled GSA TC - question does the geometry change on the air cooled bikes between a GS and a GSA (I know it does on the LC ones), wasn't aware the old one had differences other than suspension travel is up 20mm ?

and the point of the post - having ridden two this week both with just bedded in new Bridgestone tyres - I can say tyre choice makes or kills this bike - and road tyres push the forks to flex city - I can't believe the difference my stantion brace makes on my old GS. been running this ever since I went to the RS1 when they first came out - You can feel it missing within 10 yards of riding off on both the TC's I rode this week


first test ride nearly fell off multiple times on warm dry roads, riding slower than than your grand mother would ride on a slow day

Product Code Pattern name Tyre size Load & Speed Tube Type Vehicle Warranty Marking UM marking
Battlax BT-023
4871 BT023F 110/80 ZR19 M/C (59W) TL
3435 BT023R 150/70 ZR17 M/C (69W) TL
Touring MOTORCYCLE TYRE - manu claim
Safety in the wet
Excellent mileage, quality construction and proven durability
Balanced performance
Ultimate comfort
Variety of specs

Reality - dangerous lethal death-trap - nearly fell off as the front washed out at walking pace driving off the forecourt - and it did this every tiny corner for the entire road test - hideous wayward behaviour only just able to keep the bike upright at 15% of bikes capability

I either had one of these 10 years back or it was their first attempt in this size, when they first did a 19" road based tyre - it felt much the same it only lasted 100 miles, before I said get it off - back then it had felt deadly as I left the tyre shop in the first 20 yards - fixed back then by swapping it for my first Dunlop road smart 1

the bike I just bought has
Battlax A41
10562 A41F 110/80 R19 M/C 59V TL
10568 A41R 150/70 R17 M/C 69V TL
Adventure MOTORCYCLE TYRE - manu claim
Contact feel
Wet performance
Handling and grip
Flexible, durable, reliable

Reality - dangerous and unpleasant, vague, wishy-washy fumbling mess - a lot better then the BT023 and if stupid or brave, you could get to 45% of bikes capability with practice. But one needs to approach things very differently you tip it in let the tyre and forks recover then a bit more over and over till you are sort of still on the bike coming out of the bend

massive pressure sensitivity - asked they put a lot of air in as nearly dropped the one with BT023 at 2.2 bar in the front. Put in 2.5 bar in and it seemed bearable for a trepid test ride - picked it up they had it at 2.7 bar and was lethal (more like the BT023...) So I stopped and let some out and overdid it, left with 2.0 bar and oddly it was less hideous ??? - its odd tyre brand these days - but checking their site just now, on the a41's they seem to say run the 120 70 19 on the early GS bikes

My GS Road based tyre history - as above re Bridgestone hell, fixed with the the RS1, then

Michelin Road Pilot 3 - dangerous and unpleasant, vague, wishy-washy fumbling mess - a lot better then the A41 could get to 65% of bikes capability with practice. But can get to 95% if you push tyre pressure up to 2.7 bar in the front to reduce dangerous sidewall flex

this replaced the RS1 and was a mistake, went back to death-trap Bridgestone mess type handling, I hated it - it was noisy and kept making the bike do stoppies. Years later my brother and I realised it flattened down to the rim altering geometry and giving massive contact patch tipping it on its head when braking decisively

Dunlop RS1, 2 or 3 - all felt much the same - ride it like you stole it, behaves normally everywhere, lets you throw it at any bend any way you want , far more capable than you or the bike - each time its a bit better and now the RS4 is out (but can't get a 110 80 19) but now I've tried two of the early 110 80 size happy to run the wrong bigger one like I have for 8 years on the front on my Hex head - never does stoppies, is just normal and all the RS series suit the bikes funny suspension

Playing with the ESA damping modes also makes a huge change to the front end feel
comfort = dangerous, front end washes out in a scary manner under gentle riding conditions
normal = much closer to normal, front end washes out much less, if you ride slow might never know anything is wrong
sport = getting there - still needs help, more front rebound, and less rear compression and we'd be on to something

Never been on a bike in 45 years where tiny settings on suspension set up like this can have a dramatic road safety effect - I hope its somehow making the Bridgestone mess behave less erratically - and its not some dangerous quirk of unsuitable (for road use) adventure geometry changes

and in case you just think I'm an idiot ( I don't mind) and I agree the feel or the concrete metz toruances gave by far the best feel on the front-end - its just they never had any grip whatsoever - so it was really dangerous, as it goads you to ride at 120%, but has grip that's really only safe at 50% of what the bike can do - yet the RS tyres let you do it all safer and more comfortably

I guess other brands might have got it right - but if bridgestone I always liked to use on other bikes, now get things so terribly wrong these days and Dunlop will win all the races yet again this week - and I know they'll work with telelever suspension - I don't need to die or spend money testing others tyres for them... https://www.iomtt.com/tt-info
 
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I think my friend, the problem is you ;)

I had an 06 Hexhead, came with Metzeler Karoo 3's fitted, noisy and very stiff, no flex from the carcass at all

Having run Metzelers previously in road guise tyres, I know that they favour stiffness and are very hard wearing

So they were removed, and Avon Trail riders fitted, Night and day is the expression, gone was the noise lol, but you could feel the road, and the softer carcass and tread pattern, gave far more confidence

than the Karoo, bear in mind this was a brand new brand of tyre on a new bike as well

The Trail riders eventually wore out, and due to the success of the Trail rider, stocks were like rocking horse shit, Only tyres available - Metzeler Tourance

Hello stiff carcass and hard rubber!, Once again the Metzelers were true to form, and any confidence gained via the Avon's took a step back as I had to relearn the Metzelers , they are buggers when new

They take ages to bed in, 200 miles for the Avon's, double if not treble it for the Metzelers, they were skittish in the dry and not very grippy in the wet, a few squeaky bum moments !!

And then they came alive, super grippy in the dry, and equally as grippy in the wet. As good as the Avon's

Then came the LC, Bike came fitted with Tourance Next's, absolutely bloody awful, so much so they only got two trips , once home, and once to have them changed to Trail riders.. and normal service was resumed

The Trail riders in the LC sizes offer the same levels of grip and performance wet or dry .. many a time I've thrown the bike into a roundabout only to think, its a 1200 not a 125 lol

Then I had a extended loan 1250 Rallye, no crash bars (eek) and fitted with Bridgestone road biased tyre's. Hmm should be fun

It was , I went right up to western Scotland, mid winter, through some horrendous rain , snow, ice, & fully loaded, with panniers and a big bag on the back, with temps little above freezing

The tyres never gave me any cause for concern, big grippy hoops of rubber, as good as the Trail rider and Tourance. in the dry and wet.

Tyres are subjective, that's true, but 90% of the problem is confidence, and if you don't trust the tyre you never will

Change them , and put a brand on you have used before, then suddenly your new tyre will be the muts nuts :)
 
just got a new bike - an air cooled GSA TC - question does the geometry change on the air cooled bikes between a GS and a GSA (I know it does on the LC ones), wasn't aware the old one had differences other than suspension travel is up 20mm ?
Yes the geometry changes.

and road tyres push the forks to flex city
wut?
 
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Buy a better Bridgestone tyre . I ran T31s Evo which I loved on my Crosstourer before then trying A41s because the were chesper and my mate can ride the wheels off his GSA hex riding on them . Whilst I never had a problem with them I didn’t enjoy them as much as the quicker steering Evos. I’m with JB in that my favourite tyre on my GS Hexhead was Conti TA3s.
 
Never had any of the problems you describe with multiple different brands of tyres on my twin Cams.
Could it be that your pressure setting are in psi and you think they are in bar?
I know the mechanic at JCs in Dunded once got on to me for having my tyre pressure's way too high. Because he was reading it as 3.6 bar, not 36psi.
Just a thought.

Sent from my SM-A226B using Tapatalk
 
I have Conti Road Attack 2’s on my 1150. Fantastic tyres! :thumb2
 
and road tyres push the forks to flex city


yes - big time

a telelever front end moves in an arc (following the wishbone), thus the top "triple clamp" of the yokes is no longer a clamp they are just ball joints !!! - which means we are leaving only the bottom yoke to try and hold the entire front end together (yes, the wishbone does a bit and takes lots of braking forces and makes for a respectable anti-dive set up, plus it gets a damper unit that's less of a muddle than telescopic forks are with the damping hoping to work inside - but never really has).

So the only element that makes telescopic forks a viable front end for a motorcycle, has been removed by fitting the necessary ball joints on a telelever set up - Meaning there is no longer any basic engineering principles involved to get the fork tubes to work as a structural pair - With telelever they become an independent misbehaving muddle up, with almost zero structural integrity.

The reason no one has ever noticed was because with trail tyres, there has never been any grip at all. Thus BMW never noticed their forks would wobble about out of control if the front tyre ever had any grip. - If we want proof, the 5 recalls on the LC bike's where they downsized the stantions ought to be enough. After moving the LC bikes to weaker forks with thin wall, lower diameter pipe cleaners, they keep making the ball joints fall out - as the weaker forks cope even more badly and everyone dies, just as they did on the launch event !!! and indeed its why the launch event in RSA was scrapped mid session ....thinking about the real cause ought to get people on the page I'm on.

When I first tried road tyres on my HEX GS about 13 years back - I had the rear tourance wear out first - it was plain dangerous hopping and kicking sideways off bumps in the extreme, and letting go on the power coming out of corners - its lack of grip is why you didn't notice the front struggling - the back was trying to kill you first. The bike was fun on these - behaved consistently well - but pressing on there is not the road tyre levels of grip available, nor indeed any comfort. At replacement I went at the time to the lower profile new bridgestone road tyre rear, and it was brilliant. Gripped really well, massive improvement in comfort and worked perfectly with the worn tourance front. And the shorter gearing masked some engine map foibles and let the bike go up the road far faster - but now I was pushing on big time and the no feel front was going to let me down one day - as it wore, I eagerly looked to get the matching front so I had a pair of real tyres, in sizes bridgestone recco'd

but riding out from micheldever - the thing was horrific - they closed as I left. But I knew it was all wrong and an unsuitable design inside 5 metres, but I convinced myself it was just the bedding in process. So I rode to see my brother and we discussed tyres - it would now go from severe near drop it understeer, to wild oversteer multiple times on the same long sweeping bend and was getting worse and worse and at walking pace I could get 4" of bar movement each side as the forks flexed failing to tell the tyre what I wanted to do !!! I found it almost impossible to ride under 12 mph the forks are plain not strong enough to cope with a tyre that knew there was tarmac beneath it.

Within 100 miles micheldever swapped it out at no charge, and I moved to the just out Dunlop Road Smart 1 - the difference was interesting - the low speed stuff wasn't right but it was safe, predicable and you could actually ride the bike. The interesting bit was above 20mph everything about the Dunlop was all normal. Long sweeping bends this tyre was 100% normal - I never really felt the bridgestone was faulty - just a modern understeering mess for modern rider's (who can't), fitted on a heavy bike with funny suspension that really needed other side wall strengths.

As I started to trust the bike again on the RS1 Front and Bridgestone rear, as the front tyre bedded in, I could go much, much harder. But its was in big boy 120mph rapid direction changes, (where especially on high speed S bends) you'd easily get 8" of bar end movement in both directions - around 16" of bar slop and a few millisecond delays waiting for the wheel to respond to rider inputs - it was horrible scary and slow. On bends you know you can video the effect really easily and see what a dangerous design it is . And through basic engineering principles / thinking its going to cause something to break...

There isn't really much we can do - without massive costs and engineering resource - the front spindle with a far bigger diameter, re make the bottom yoke with a much bigger stronger design and more clamping area etc. - so I opted to do the spindle up FT, check the bottom yoke is FT, and then on the stantions - as a test to see if I could get clearance for safe operation - I made a flimsy brace joining the tops of the tubes just below the ball joints and the effect is astonishing - in my mind what I did it too weak to real add value but on the road the transformation took the 16" of slop down to 1 or 2 inches - its been there for 11 years now...

The effect is light and day and riding last week on those two GS' with a dangerous design of tyre - I can feel all the horrible flex my hex no longer has - its shocking that my little bracket has so much effect - no BS you can literally feel the difference with in 1 metre of pulling away - it ought to be on the bike from the factory - and the LC bikes should have upped the fork diameter and lower yoke not weakened it... so no wonder they have ongoing issues

As for the Road Smarts, each few years the they improved and became even more suitable for the GS, the RS2 I guess was 35% better everywhere stressing the forks less and low speed went mostly normal. Then the RS3 took it all to pretty much normal with my brace - been waiting 2 years to try the RS4 but covid meant USA got it a year before we did and its hard to come by....

rossi couldn't ride a bike that understeered - when he came off Dunlop's (as they all moved to Michelin) he became a 9th place guy... very sad


I think my friend, the problem is you ;)

I had an 06 Hexhead, came with Metzeler Karoo 3's fitted, noisy and very stiff, no flex from the carcass at all

Having run Metzelers previously in road guise tyres, I know that they favour stiffness and are very hard wearing

So they were removed, and Avon Trail riders fitted, Night and day is the expression, gone was the noise lol, but you could feel the road, and the softer carcass and tread pattern, gave far more confidence......

thanks, I read and understood your points - what I picked up - seems you are more agreeing with my points, rather than "its me" ? maybe the extra info above here helps explains whats going wrong - due to haphazard engineering principles in play by the manu
 
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The reason no one has ever noticed was because with trail tyres, there has never been any grip at all. Thus BMW never noticed their forks would wobble about out of control if the front tyre ever had any grip.
This is because you are convinced that you are the first person on the planet to put road tyres on a GS?

With all due respect, you are seriously overthinking it. (Especially for the hexheads)

When I first tried road tyres on my HEX GS about 13 years back - I had the rear tourance wear out first - it was plain dangerous hopping and kicking sideways off bumps in the extreme, and letting go on the power coming out of corners - its lack of grip is why you didn't notice the front struggling - the back was trying to kill you first. The bike was fun on these - behaved consistently well - but pressing on there is not the road tyre levels of grip available, nor indeed any comfort.
This happens to you alone.
I remember reading your posts about the traction control lighting up on your GS and some other issues you've had over time. Again, based on all the issues you've been reporting, I'd tend to say this is mostly a problem that mostly just you are experiencing.

To be clear: I'm not taking the piss or anything. Just a consideration.

I have an hexhead GSA. Direction changes at 120mph are not exactly super fast, but the bike is fairly stable (all considering – also, in my case, not that much of chicanes at that speed).
It is, still, like riding a bowl of spaghetti if compared, say, to my HP2 Sport (to keep it within boxer engined bikes :D ) but that is normal and expected.
I started having an annoying wobble at higher speeds (>100mph) some time back and I took me forever... trying anything, before realising that it was just the shocks needing another service :D
Funnily enough the bike was more stable on faster corners as it would be "pushed down" keeping the shocks compressed.
 
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You mention 120mph direction changes, methinks you have simply bought the wrong bike.GS and GSA aren't high speed sports bikes, they are heavy trail and touring bikes.Buy a sports bike if you want to ride like that.Not surprised you are tying the bike in knots and wondering why it is struggling.
 
No not agreeing,

Pointing out, yes tyres are different from each manufacturer,

some take more time to bed in from others

You didn't like the Battlax's i thought they were very capable tyre

And that 90% of a tyres perception, is down to the user
 
I’ve been happy with every with every tyre choice I’ve tried . I don’t think it’s the tyres that’s causing the distress .
Continue Trail attack at the moment but may try Bridgestones again next . Hey Ho
 
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I'm confused. If the engineering of the suspension of this bike and performance of tyres in general is so crap, why are you actually riding a GS, or any motorcycle? You do not seem to be enjoying it. Buy a different bike more suited to your riding requirement, or find another hobby you can enjoy.
 
And there are no ball joints at the top yolk! Bushes that flex for And aft slightly following the telelever arc.
When riding along stick your fingers there to feel the movement

Sent from my SM-A226B using Tapatalk
 
This is because you are convinced that you are the first person on the planet to put road tyres on a GS?

With all due respect, you are seriously overthinking it. (Especially for the hexheads)


This happens to you alone.
I remember reading your posts about the traction control lighting up on your GS and some other issues you've had over time. Again, based on all the issues you've been reporting, I'd tend to say this is mostly a problem that mostly just you are experiencing.


no one is saying I'm the first to fit road tyres - all I'm saying is the forks cope on trail rubber - but the extra grip on road rubber causes the forks to flex very noticeably - I had never had this issue or even an inkling it could behave like that when I had the original tourance tyres (and I'd done 2500 miles on them...), but as soon as road rubber went on you can feel the flexy forks just tickling along at walking pace and now 12 years on, two more 100% standard low mile (less than 10k ) bikes are doing it on road based rubber - and in the case of the BT023s I felt it within 3 meters and the A41's inside 25 meters of ever riding the bikes

as for traction control - oh yes that bug is alive and well - quite used to switching to S on my old GS every ride now, and its rare I forget - but yesterday I took the GSA out of a carpark in bracknell - hot day, dry tarmac, bike engine and tyres still hot and somehow I forgot to move to S before I set off - rode on to the dual carriageway, gave it about half throttle to around 4k rpm- stuttering mess of confusion, WTF, second gear stuttering mess, WTF is going on, this is utter it madness, it was fine when I parked it, changed to third stuttering got worse - holly cow whats gone wrong with the bike??? ... Oh I forgot S mode

in the dry, the old or the new bike simply cannot break traction in conditions where applying full throttle is advisable - they don't make enough power to do this - so why is it fitted with a computer that turns the engine off? unless totally incompetent modern tyres need about 180bhp before the rear tyre needs any form of nanny support
 
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You mention 120mph direction changes, methinks you have simply bought the wrong bike.GS and GSA aren't high speed sports bikes, they are heavy trail and touring bikes.Buy a sports bike if you want to ride like that.Not surprised you are tying the bike in knots and wondering why it is struggling.

and

I'm confused. If the engineering of the suspension of this bike and performance of tyres in general is so crap, why are you actually riding a GS, or any motorcycle? You do not seem to be enjoying it. Buy a different bike more suited to your riding requirement, or find another hobby you can enjoy.

I've had sports bikes - GS' are much quicker and far safer in the real word... zzr1400 with akropovic, TL1000s, Fireblades, 996, all much slower and for more effort, my KTM 1290 made loads of go - but the thing couldn't hope to keep up
 


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