Bicycle Mechanics - Affect of stem angle/length on steering stability?

Hello,

I have a threaded quill stem now and want to switch to an adapter:

http://www.nashbar.com/profile.cfm?category=119&subcategory=1186&brand=&sku=9755&storetype=&estoreid=&pagename= (http://)

And add a threadless stem to it.

I currently have an adjustable rise stem that came with my 2004 Bianchi Strada and I don't like it because:

1. The piece of metal that locks the angle squeeks (although I've fixed that somewhat with the addition of some grease).

2. The stem flexes a lot and I feel like I'm giving up a lot of energy to this.

So, once I go to this threadless adapter, I have to pick out a new stem and choose its angle and length.

What I want to know is:

1. What affect does the angle play in steering stability?

2. What affect does the stem length play in steering stability?

I can test out different angles on my current setup by changing the angle and them adjusting the rise to get the handlebars back to the same relative distance to the seat height. But I can't play with the stem length. My guess is that the shorter the stem, the less sensitive the steering (closer to the turning axis).

Any thoughts?

Thanks,

Warren

Hello,

I have a threaded quill stem now and want to switch to an adapter:

http://www.nashbar.com/profile.cfm?category=119&subcategory=1186&brand=&sku=9755&storetype=&estoreid=&pagename= (http://)

And add a threadless stem to it.

I currently have an adjustable rise stem that came with my 2004 Bianchi Strada and I don't like it because:

1. The piece of metal that locks the angle squeeks (although I've fixed that somewhat with the addition of some grease).

2. The stem flexes a lot and I feel like I'm giving up a lot of energy to this.

So, once I go to this threadless adapter, I have to pick out a new stem and choose its angle and length.

What I want to know is:

1. What affect does the angle play in steering stability?

2. What affect does the stem length play in steering stability?

I can test out different angles on my current setup by changing the angle and them adjusting the rise to get the handlebars back to the same relative distance to the seat height. But I can't play with the stem length. My guess is that the shorter the stem, the less sensitive the steering (closer to the turning axis).

Any thoughts?

Thanks,

WarrenPick the angle and length that gives the bestest fit and let the stability nonsense fall where it will. And actually, shorter stems make steering imput more sensitive.

Pick the angle and length that gives the bestest fit and let the stability nonsense fall where it will. And actually, shorter stems make steering imput more sensitive.

But how do I determine that? If I keep the position of the handlebars the same (relative distance in front of and above/below the seat) beacuse it works for me, I could pick out several different angles/lengths that would place the handlebars in the same position (by adjusting the height to compensate), right?

But how do I determine that? If I keep the position of the handlebars the same (relative distance in front of and above/below the seat) beacuse it works for me, I could pick out several different angles/lengths that would place the handlebars in the same position (by adjusting the height to compensate), right?sydney is just the idea guy. someone else can take a shot at the details. There is a reason sydney has a couple boxes of both quill and threadless stems and why sydney now knows what stem length and angle goes with all the toptube lengths and frame sizes sydney has.