shortnsalty

On my GT series 4 I notice its a little twitchy. Unlike my old schwin I really can't let go of handle bars. What is it that makes a bike track or ride a line better..the neck tube or forks or both?
This will affect my next purchase.

shortnsalty

I might add I'm not to concerned about letting go of handle bars I just don't like the fact that if I'm riding in a grp and I go to drink its a "be very carefull" moment. I've nvr really riden anyone else's bike to compare to my GT except the old schwin to whereas I would feel comfortable riding between two riders with no hands and still hold a line. Up

Campag4life

yes...its the neck tube angle and fork rake...but also the overall wheelbase and chain stay length...and even body weight distribution in the mix.
Old schwinn's were pretty relaxed by modern race bike standards. If you prefer a slightly slower handling bike...I do as well...choose a comfort geometry which tend to more laid out in angles to compensate for less weight on the handlebars.

Looigi

Some may be somewhat less stable than others, but I don't know of any road bike where you can't ride no-hands going 12 mph or more. FWIW: A slightly loose headset, very tight headset, or one with notched bearings can be difficult or impossible to ride no-hands.

halfspeed

https://www.dclxvi.org/chunk/tech/trail/

shortnsalty

Thx all.

Seattle Forrest

It's already been pointed out that it's mathematically somewhat complicated. There are some rules of thumb, like shorter chainstays make for a "twitchier" or "faster handling" bike.

But if you're asking because you plan to buy another bike at some point and want it to be less twitchy ... the best measurement is a good test ride.

Chris Pringle

Your GT Series 4 has a front-end with a 54mm trail. This is considered in the "medium" trail category. Combine that, however, with your 410mm chainstay length (short) and you end up with a twitchy bike. Your bike will excel in criterium races, for example. Most people get used to the feel over time. But if it makes you uncomfortable on your Sunday group rides, long-distance rides where you'll eventually get tired, etc., then N+1 is in your horizon. A few things that you can do to increase "trail" (which will make your bike a little more stable) is to run larger tires (if your frame has room.) If you tend to ride with any kind of gear, you might also benefit a bit by putting it up front (e.g., handlebar bag.) Other than those, a different high-trail bike might be needed. I personally like bikes around 57-60mm trail on the front-end and 430-440mm chainstay length. They offer a good balance. You can go higher if you really want a stable feel. Obviously, all depends on one's intentions with the bike.

curiouskid55

My guess is that its your wheels not your frame. Might be out of true, out of round, or too light to produce the handling you are comfortable with. Also too heavy a hand on the drops can make a bike jump around.

Mike F

Sometimes a short stem can add to that twitchy feeling.