Giant Defy handling issues..any ideas?

[runner]

My giant defy is acting somwhat strange. The steering/handling appears somewhat dangerous and I feel as if I am not in control and that any minute I will hit the ground! It is very hard to describe but the steering is somewhat unresponsive....do you think the headset needs replacing? I can't think of anything else that might be causing the problem....perhaps you could suggest?

 

[fixedfixer]

Lift bike off ground, turn bars from side to side - does it feel smooth or notchy and rough? If not smooth then headset needs attention. Also check your tyre pressure. Soft tyre will make it feel a bit odd.

 

[2Loose]

If this has recently started happening (and not just you getting used to the twitchy handling) then I would guess that the headset bearings need regreasing\replacing.

Pretty easy to do, even easier to check as you don't need to remove everything, just expose the bearings by dropping the fork a couple of inches so that you can inspect them.

 

[sdr gb]

Lift bike off ground, turn bars from side to side - does it feel smooth or notchy and rough? If not smooth then headset needs attention.

Another way to check the headset is to apply the front brake and rock the bike backwards and forwards. If you can feel any play, then the headset needs adjusting.

Also, if you are running new tyres, these can feel a bit sketchy for the first few rides.

 

[Moodyman]

If you're steering is very light - i.e turns without you really trying, you need to tighten up the headset.

Loosen the two bolts on the stem, then tighten the headset bolt, then re-tighten the two stem bolts.

If it's a bike you ride regularly then you might be having a 'it's not my bike feeling' as discussed here.

https://www.cyclechat.net/

 

[Bicycle]

My giant defy is acting somwhat strange. The steering/handling appears somewhat dangerous and I feel as if I am not in control and that any minute I will hit the ground! It is very hard to describe but the steering is somewhat unresponsive....do you think the headset needs replacing? I can't think of anything else that might be causing the problem....perhaps you could suggest?

Unresponsive or unpredictably responsive steering certainly sounds like the headset. It should have a smooth, slightly cushioned feeling, like the volume control on an upmarket stereo.

That's what I'd check first.

If that's fine (and assuming tyre pressures are OK) then it may be worth looking at both sets of wheel bearings. If either wheel wobbles even a little, then those bearings are no bon.

This might sound an odd place to look, but either set of bearings will make the bike feel directionally unpredicatable if they are Donald.

I'm assuming (apologies) that all the clamps for your bars and stem are nicey-tighty. That one's a bit of a long shot.

If it's not headset, wheel bearings, tyre pressures or loose clamps, are your handlebars slightly skewed after dropping the bike?

If you've had it a while, you may not notice them being a dgree or so out, but you may feel constantly as though you're having to steer slightly off the line you want to follow.

All the above have happened to me over the years, all took a few moments of Rodin-like thought to detect and all made the steering feel wibbledy-wobbledy or unpredictable.

Good luck.

 

[EYE-TYE-MAD]

My giant defy is acting somwhat strange. The steering/handling appears somewhat dangerous and I feel as if I am not in control and that any minute I will hit the ground! It is very hard to describe but the steering is somewhat unresponsive....do you think the headset needs replacing? I can't think of anything else that might be causing the problem....perhaps you could suggest?

Sounds like the stem neck bolts are loose, however, you can have steering & handling issues if the frame is too small, particularly if the top tube is short.

 

[bucksgill]

Don't want to take away from the OP but it is somewhat on topic:

I literally just noticed before reading this, having never noticed before but that doesn't mean it wasn't there. But with the front end of the ground and turning the handle bars there was a little noise and roughness. A bit like a non-smooth running ball bearing. It's a regular 'vibration' in that its always the same kinda feeling and not stop start.

Could this be what fixedfixer is talking about and if so what do I need to do with my headset/ what really is the headset?

EDIT: If you want me to make a new thread so that the OP can get his issue sorted without me getting in the way then I shall. Although I have just seen then it's originally from November 2011 haha

 

[2Loose]

Bucksgill, this is exactly what fixedfixer was talking about (3months ago). A grainy, or notchy feel when turning the bars is to do with something not right in the headset area. Normally (hopefully) it is just the bearings running dry of grease, or ultimately needing replacement. To sort it out, the handlebars need removing from the stem and the fork dropped out so that they can be replaced, or regreased.

Headset servicing (from the late, great Sheldon) http://sheldonbrown.com/headsets.html

 

[bucksgill]

Cheers for that 2Loose, I'll have a go at sorting it this weekend.