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)

[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

[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

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

[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 rear

Fuckenell!

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.