Thedavidimage

I just recently purchased a used bianchi sl argentin bicycle which I test rode and found to be very twitchy and unstable and almost unridable. It also appears that the headset is very gritty and possibly pitted. Is the headset the cause of this problem or are the frame angles so steep as to cause it to be unstable?

rumrunn6

can't answer your questions but if you've pumped your tire to their max pressure you might try the front tire 5-10 lbs lower. it carries less weight than the rear so it doesn't have to be as hard. a softer front tire will make it less twitchy. but have that grit checked out

livedarklions

How are the hubs? Is there any sideways play in the wheels? Bad hubs can make things feel "twitchy and unstable".

dsaul

If the headset does not move freely, that is the problem. When we pedal, the front wheel turns slightly from side to side. It happens naturally and you don't even notice it happens unless your tires get wet and you can see the curvy line left by the front tire. When the headset doen't move freely, the front wheel isn't able to center itself an you find yourself having to manually correct it when you are pedaling. It is a very disconcerting feeling of not really having control of the bike.

indyfabz

You bought a bike after test riding it and finding it to be almost un-rideable?

dedhed

Has it been in a crash and the fork is bent?

bruce19

Sounds like this bike needs a total and thorough inspection by a professional.

noimagination

What kind of bike did you ride previously? If I've ridden my touring bike for a while, and then switch to my "race" bike, the "race" bike does feel twitchy, it takes a few miles before I feel comfortable on it.

Not saying that's your problem, it's just something to consider. Also, if the headset doesn't feel right, it's possible that someone put in a new fork and didn't install the headset properly, which also means that it's possible that they installed a fork that isn't appropriate for the frame geometry. Can you tell if the bike has the original fork?

MikeyMK

A stiff or sticky headset makes a bike horrible to ride.

Trakhak

dSaul provided the most probable explanation.

Embarrassing story: I hated the handling of one of my bikes, blaming the frame geometry, and rode it only occasionally for 5 years. Then it occurred to me that the (Allen-bolt-secured) cable hanger for the front brake might have been interfering with the headset adjustment. Loosened the Allen bolt, adjusted the headset, tightened the Allen bolt, and suddenly the bike handled like a dream.

Retro Grouch 

That's what I think too. A slightly too tight headset will feel crunchy and will require constant manual steering corrections.

hefeweizen

I just recently purchased a used bianchi sl argentin bicycle which I test rode and found to be very twitchy and unstable and almost unridable.






The frame geometry doesn't look crazy .

BlazingPedals

...or the opposite. I rode with a loose headset once. Man, I had a heck of a time trying to keep it in my lane!

mstateglfr 

Nobody here would know if your headset is pitted.
And nobody here would know why you bought a bike you can barely ride.

Thedavidimage

I purchased this bike on Ebay and test rode it after I bought it. I have purchased many bikes on eBay without problem and the headset problem was not mentioned. I just took my headset apart and it is somewhat pitted and I will replace it. I may not have been explicit enough.

smashndash

I would start with that. Even the most hyper aggressive race bikes aren’t “unridable” at speeds achievable with human power alone. Of course, if you’re talking about 40+ mph, a lot of bikes can start feeling unsettled. But road bike geometry has been a bit of a solved problem for a while. I doubt a traditional company like Bianchi would make something so unfriendly to ride. Let us know how it goes.

tim24k

Are all the spokes tight and wheels straight and true? I would definitely go all though the bike and check everything.

bpcyclist

I suspect you will find the cause of this once you've had it properly checked out by a competent mechanic. Well worth the cash outlay. That said, some bikes are just known for being a bit on the twitchy side. I bought one of those,a nice Wilier, and I did not like the ride initially, coming from an Orca. But you can learn to manage it and then, after some practice, it really isn't bothersome anymore. So, just keep that in mind. You can get accustomed to it with some practice and then, everything will be fine.