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Steering Wierdness
 

[Closed] Steering Wierdness

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[#9757431]

The steering on my bike feels weird,hard to explain but a bit like turning a gyroscope, it seems to pull to one side then the other, very odd.

It's a newly built up bike and it rode fine the first couple of rides.
Then I replaced the 2.8 rocket Ron with a 2.8 Nobby Nic and tightened the headset bearings as there was a bit of play.

Now it feels weird, I initially though it was the front wheel bearing as there was a bit of play in it but I've now changed them and it's still the same.

Any ideas?

cheers


 
Posted : 07/01/2018 8:51 pm
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Sounds like you're running to low a pressure and it's self steering.


 
Posted : 07/01/2018 8:54 pm
 JoeG
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You're not used to the added weight of a 2.8tire; more rotating mass. The 2.8 has a lot more rotational inertia than a 2.1 tire.


 
Posted : 07/01/2018 8:55 pm
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Is the bike / forks straight and true?
Tyre and wheel central?
Bars symmetrical?
Headset gearings greased and clean? ( I had bike that had a dodgy jammed bearing that felt 'odd' in steering ways)


 
Posted : 07/01/2018 9:00 pm
 mm93
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Headset too tight?


 
Posted : 07/01/2018 9:16 pm
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frame/forks are new and everything ran fine before I fitted the NN 2.8 and tightened the headset.

Could it be it's just a bigger\heavier tyre than I'm used too?
I'm not running it particularly soft but I've no idea what pressure it's at


 
Posted : 07/01/2018 9:16 pm
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Post christmas belly wobbling around?


 
Posted : 07/01/2018 9:19 pm
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Yeah sounds like headset bearings. When they start going on my cross bike it gives exactly the weird feeling steering against a gyroscope feeling the OP describes, and which I guess is what's happening as bikes naturally want to go in wavy lines...

So see if there's any stiffness/grinding or whatever when you turn the bars, if so it's a service. Cheap easy job. Not that Ive done it..

Ah ha! "tightened the headset". Too tight?


 
Posted : 07/01/2018 9:20 pm
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Was the headset new on the new build? If they have been loose for a while or on another bike, the balls in the bearing races can "slump" into bearing surfaces causing them to fall one way or the other when tightened. It's difficult to diagnose but can cause the symptoms you are experiencing.


 
Posted : 07/01/2018 9:22 pm
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Headset is new, wonder if I've overtightened it and buggered up the bearings?
I've just redone it and the weirdness is still there.


 
Posted : 07/01/2018 9:24 pm
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It rode fine with a 2.8 Rocket Ron so I'm not sure its the tyre size causing it.


 
Posted : 07/01/2018 9:25 pm
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It rode fine with a 2.8 Rocket Ron so I'm not sure its the tyre size causing it.

It's not the size it's the different tread pattern.
Put the Ron back on and I bet you don't feel it any more.
What you're describing is self steer. Happens really bad with some full on fat tyres and I've felt it to a much lesser extent on some 2.8 tyres too.

https://www.google.co.uk/search?q=fatbike+self+steer&oq=fatbike+self+steer&aqs=chrome..69i57j0.8350j0j7&sourceid=chrome&ie=UTF-8


 
Posted : 07/01/2018 9:44 pm
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Sounds like low-pressure self-steering


 
Posted : 07/01/2018 9:45 pm
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Makes sense, first ride with the new tyres fitted I stared out with the tyres quite hard and let a bit of pressure out after a few miles. They then felt a bit odd on the next bit of road I hit.
Do you just put up with it.
The tyre's aren't really low pressure in fact I was going to let a bit more air out.Will that make it worse?


 
Posted : 07/01/2018 10:15 pm
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It will on tarmac yes.


 
Posted : 07/01/2018 10:19 pm
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Are the bars swinging freely left to right when you lift the front of the bike by the top tube?


 
Posted : 07/01/2018 10:22 pm
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Everything's moving as it should. All spokes are tight front and back, change wheel bearings on front because they had a tiny bit of play and redone headset.


 
Posted : 07/01/2018 10:26 pm
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If it is self steer you will probably notice it on off camber trails as well.
Lower pressure will make it worse.
Some tyres patterns are worse than others.


 
Posted : 07/01/2018 10:46 pm