Freaky handling

[baffa]

Hey guys,

The bike has felt like it is more willing to tip into corners recently, which was odd, and I thought it was just me, but I went for a ride yesterday and it had a really freaky handling trait. Basically the rear wheel feels like its rolling around, or stepping out when you lean over.

Imagine leaning left into a corner, and feeling the rear move slightly to the right, causing you to lean over more than you intended. Thats what it feels like, and feels a bit disconcerting.
I was hoping it was just low pressure on the rear tyre. I normally run the rear on 42 psi (Cold).
I checked it on the way home and it was just under 40 hot, so I put a little extra air in, but havent had a chance to check the pressure cold, so it potentially could still be a bit lower.

I was thinking maybe the rear wheel bearings or something like that have let go?

Planning to head down to a bike shop and get it looked at when I can, but has anyone had anything similair?

[ducatilover]

I've had it from:
Too much tyre pressure
Too little tyre pressure
Not enough damping
Low preload
Crap tyre, happy right wrist
And the most common form of ruining a bike's handling, me

[Gremlin]

If you also checked it on the way home, did you vary which pump you use to check? Stations can vary a lot.

Check the stuff ducatilover said. I have indeed had it where I'm convinced the pressures are wrong, checked them, and they're spot on. Your head is pretty powerful and you could swear something is wrong, when it isn't.

Yes, bearings might do that, but I've had toasted bearings and the bike rode fine (or maybe my head fixed it) :lol:

[James Deuce]

Are you sure your rear tyre hasn't squared off? It can give a sensation of suddenly tipping into the corner as you roll over the lip and onto the steeper edge profile, made relativity steeper by the flatter centre section.

[caspernz]

Are you sure your rear tyre hasn't squared off? It can give a sensation of suddenly tipping into the corner as you roll over the lip and onto the steeper edge profile, made relativity steeper by the flatter centre section.

Yep, that would be my diagnosis of the symptoms described...rear tyre starting to square off.

Mind you, tyre pressure being too low can make this seem worse than it needs to be. A good quality tyre pressure gauge is worthwhile :2thumbsup

[HenryDorsetCase]

Yep, that would be my diagnosis of the symptoms described...rear tyre starting to square off.

Mind you, tyre pressure being too low can make this seem worse than it needs to be. A good quality tyre pressure gauge is worthwhile :2thumbsup

Agreed. I've got a couple of those Accu Gauges and a pushbike trackpump. Its all you need for adjusting and service station gauges are teh shitz.

[caspernz]

Agreed. I've got a couple of those Accu Gauges and a pushbike trackpump. Its all you need for adjusting and service station gauges are teh shitz.

Haha, yeah I've got a bicycle type standup airpump that I use on the bike as well as car tyres. Then an Oxford digital gauge with a bleed valve to drop the pressure to the exact one I want...much better and easier than fiddling with servo tyre pumps :2thumbsup

[Drew]

42 PSI cold! Fuck me that's a lot. What type of tyre is it? Not relevant if it's what you always use, and you are getting a difference. I'm just curious.

Does it happen turning left and right?

[Gremlin]

42 PSI cold! Fuck me that's a lot. What type of tyre is it? Not relevant if it's what you always use, and you are getting a difference. I'm just curious.
A lot of the big Hondas have that manufacturer recommended. CB900 and Blackbird to name 2.

[Drew]

A lot of the big Hondas have that manufacturer recommended. CB900 and Blackbird to name 2.
I certainly wouldn't pay any attention to it, but that's just me.

Any way, I ask if the symptoms are the same in both directions because it is totolly arbitrary to name possible issues withotu all the info.

[HenryDorsetCase]

42 PSI cold! Fuck me that's a lot. What type of tyre is it? Not relevant if it's what you always use, and you are getting a difference. I'm just curious.

Does it happen turning left and right?

Triumph Street Triple rec 34 front and 42 rear

[Drew]

Triumph Street Triple rec 34 front and 42 rearFuckenell!

Not on a bike I owned.

[WRT]

Triumph Street Triple rec 34 front and 42 rear

I think the Speed Trip is 36 and 42. ZX10 and 636 are also both recommended by Kwaka at 36 and 42.

[F5 Dave]

Some Contis recommend real high pressures. Aside from tyres which would be my first call, would be steering head, but other bearings could be suspect. Get a mate to help hold the bike & check the steering with front off ground & check for any stiffness or notch in the centre, & wobble the wheels checking for play.

[baffa]

Ive always run 40-42 rear, 36-38 front. Feels best to me.

As I said, I checked the pressure when it was warm, and it was sitting around 38 or so, so Im guessing it could have been closer to mid 30s cold.

Thanks for the feedback guys. I need to have the suspension given a once over, and check the rear wheel bearings. Plenty of tread left on the tyre but I do mostly commute so it is starting to square off a little.

It would be easier if I could just ignore small problems, but if something feels off on the bike I dont feel as if I can trust it. Too cautious I guess.

[mossy1200]

You guys run them high.

I run 32 front and 34 rear even when 2 up.
I like to judge mine by the colour they run at.
Blue is low pressure and overheating and grey is to much pressure and running to cold.

Tip in speed is most likely shape in the tire and rolling off a worn out centre line.

[F5 Dave]

That's under inflated for most tyres on big bikes for road use. The manufacturers know a thing or two about their own product & tyre construction has moved on from the 80s.

[mossy1200]

That's under inflated for most tyres on big bikes for road use. The manufacturers know a thing or two about their own product & tyre construction has moved on from the 80s.

They get hot enough and stick to the road ok.
Maybe touring tyres would last better with 40 odd but I run sports tyres and 5tho out of rear is fine for me and then a new set goes on.

[hayd3n]

36 f 42 rear here
has been for most of my bikes

[James Deuce]

A tiny bit of squaring can feel like a vertiginous precipice because you have to mount the lip and then drop off of it. I think the square tyre is most likely.

[skippa1]

A tiny bit of squaring can feel like a vertiginous precipice because you have to mount the lip and then drop off of it. I think the square tyre is most likely.

wot he said ^

[actungbaby]

[QUOTE=baffa;1130413279]Hey guys,

The bike has felt like it is more willing to tip into corners recently, which was odd, and I thought it was just me, but I went for a ride yesterday and it had a really freaky handling trait. Basically the rear wheel feels like its rolling around, or stepping out when you lean over.

I rode my cosins suzuki 450 twin i had one at the time and omg seriously i think was going crash it

after going few feet he rode it at speed i guess was used to it the front tire was like trianglated

Badly worn so felt like it wantede to veer suddely i think was scarest thing ever ridden hehe

[_Shrek_]

have you checked that the tripple clamps are tight?

are all the bolts in also?

this would cause the bike to drop in the corners as well

[pritch]

Triumph Street Triple rec 34 front and 42 rear

Speed Triple too.

[ellipsis]

A tiny bit of squaring can feel like a vertiginous precipice because you have to mount the lip and then drop off of it. I think the square tyre is most likely.

...wot 'e sed...

[speights_bud]

Check yer rear axle, same descripton happened to someone on the race track recently and they couldn't figure it out until they decided to pull it apart.

[Banditbandit]

Some Contis recommend real high pressures. Aside from tyres which would be my first call, would be steering head, but other bearings could be suspect. Get a mate to help hold the bike & check the steering with front off ground & check for any stiffness or notch in the centre, & wobble the wheels checking for play.

Yeah .. Conti recommended 42psi on the rear of my 650 (Road Attacks) the 1250 Bandit recommends 42 psi rear - 38 on the front standard. 4-5 pounds under that recommendation and the bike feels odd ...

[Banditbandit]

A tiny bit of squaring can feel like a vertiginous precipice because you have to mount the lip and then drop off of it. I think the square tyre is most likely.

Yup ... put new tyrs on the 650 about three weeks ago -the rear was shot (bald asnd square) and the front was OK but getting there (Triangulated) so I changed both - I could not believe how much difference they made ... I had got used to the old tyres over the 5,000klicks I'd had the rear ...

[ducatilover]

Yeah .. Conti recommended 42psi on the rear of my 650 (Road Attacks) the 1250 Bandit recommends 42 psi rear - 38 on the front standard. 4-5 pounds under that recommendation and the bike feels odd ...
That seems a bit to me (not arguing) I run 38r/34f on my ZX6 and it feels excellent, if the rear drops below 35ish it'll slide around a lot and lose traction in the wet

[Drew]

if the rear drops below 35ish it'll slide around a lot and lose traction in the wetThat's in your head man. The biggest loss of traction in the wet, without standing water (puddles), comes form the tyre temperature dropping and becoming less pliable. So it doesn't conform to the road surface as well. Softer tyre means more deflection/heat.

In standing water it's the tread doing it's thing. But, any tyre would need to be below 25psi before tread groves started getting closed up by tyre distortion, and then start sliding.

[baffa]

Found the problem.

A week or so ago I dropped into Cyclespot to get the chain tightened, as I didnt have a 26mm socket at home.

I didnt realise it, but it was after that, that the handling started feeling funny.
I was thinking about it today, and realised it felt a bit like a car with a wheel out of alignment, or broken HICAS.

Got it home and on the stand, and checked it. Sure enough, the wheel was turned several degrees to the left.
A basic fucking task and they screwed it up, potentially causing excessive wear on the chain and sprockets, as well as the disturbing handling.

Borrowed a 26mm socket and adjusted it, and what do you know, it feels ok again.

Gonna goto Cycletreads to double check then go blast Cyclespot tomorrow.

[Ocean1]

That's in your head man. The biggest loss of traction in the wet, without standing water (puddles), comes form the tyre temperature dropping and becoming less pliable. So it doesn't conform to the road surface as well. Softer tyre means more deflection/heat.

In standing water it's the tread doing it's thing. But, any tyre would need to be below 25psi before tread groves started getting closed up by tyre distortion, and then start sliding.

Funny thing with the Buell, I run 36/36 on pilot powers. That's 4psi less than both Mr Buell and Mr Michelin recommend on the back, 2 less on the front. Couple of times I've left it a bit long between checks, and they lose pressure fairly quickly. 2 psi down on the back makes bugger all difference, little less positive in the feedback department... 34psi on the front and the front starts to feel a bit mushey. 32psi in the front and you can literally feel the sidewalls buckling.


Sure enough, the wheel was turned several degrees to the left.


Several degrees is shitloads, how far out did it look at the axle nuts?

[ducatilover]

BURN THEM ALL!!!!!!!!!!!

I was about to come in and suggest it was your vagina not gripping the seat, but you solved it

[Banditbandit]

That seems a bit to me (not arguing) I run 38r/34f on my ZX6 and it feels excellent, if the rear drops below 35ish it'll slide around a lot and lose traction in the wet

I used to think that was way high too ... but the bikes/tyres certainly handle better at those pressures - and as I say - four or five pounds down and it affects the handling ... I would not suggest running your tyres higher ... if your bike handles well with tyres at those pressures, then run them at those pressures.


That's in your head man. The biggest loss of traction in the wet, without standing water (puddles), comes form the tyre temperature dropping and becoming less pliable. So it doesn't conform to the road surface as well. Softer tyre means more deflection/heat.

In standing water it's the tread doing it's thing. But, any tyre would need to be below 25psi before tread groves started getting closed up by tyre distortion, and then start sliding.

Yes - tyres will cool down and go below optimum pressure if your tyre pressure is already at trhe bottom end of the range ...

[pritch]

Three of the last four bikes I've owned were 34 or 36 and 42. The Ducati was lower possibly 32 and 34 but there was a rider that if the roads were rough you should run higher pressures to protect the rims: 34 and 36 or thereabout?

The tyre companies say most people are running on underinflated tyres, but they don't mind because the resulting additional wear means extra sales.

[Banditbandit]

Found the problem.

A week or so ago I dropped into Cyclespot to get the chain tightened, as I didnt have a 26mm socket at home.

I didnt realise it, but it was after that, that the handling started feeling funny.
I was thinking about it today, and realised it felt a bit like a car with a wheel out of alignment, or broken HICAS.

Got it home and on the stand, and checked it. Sure enough, the wheel was turned several degrees to the left.
A basic fucking task and they screwed it up, potentially causing excessive wear on the chain and sprockets, as well as the disturbing handling.

Borrowed a 26mm socket and adjusted it, and what do you know, it feels ok again.

Gonna goto Cycletreads to double check then go blast Cyclespot tomorrow.

Sometimes I Just hate bike shops ...

Usually you can spot that problem because one hand will be getting there before the other hand ... as you'll be turning the bars slightly to compensate ...

[mulletman]

If theres 1 time i would NOT run 40+R is summer time riding thru Porters Pass (high temps and Alt)
3 of us started 36f38r (normal for me) 1 VTR1000 2 GSX1400s, got to Arthurs and we all bitched about the handleing of our bikes, squirmy like riding over pgravel (was none)checked pressures WTF
50-55 PSI rear, dropped pressures waay back - all gd then had to re adjust when we got to Hoki.

[s_devo]

I'm glad I found this thread I have the Rosso 2s and they are great. I commute about 50km each day and after about 4,000 they're starting to square off. I was starting to find a spot in my right hand turns were a sudden dip would kick in and give me a small heart attack each time. So I've been getting more and more paranoid and taking my corners slower and slower. At first I thought it was the steering bearings, but see now it's the squaring on the tires. Any solution to this or are they better off replaced? I'll probably get the Angels next time due to all the straight up commuting I'm doing.

[frogfeaturesFZR]

Replace the rear for sure, might get a few more km's from the front ?
I run a harder compound tyre on the rear FWIW.