mtb -> drop bar, weird handling

So I bought an '84 stumpjumper a couple months ago. Completely stripped it down, rebuilt what was needed, replaced a couple things here and there, and replaced the flat bar with a drop bar. The idea was to make a touring/utility bike on the cheap.

The geometry is pretty relaxed, as you would expect, but the handling seems weird to me. When I turn the bar slightly at speed it responds “normally”, but if I do any kind of sharpish cornering at lower speeds it feels like the wheel is trying to pull to that side. I get the same thing when I stand up to pedal and jerk the handlebars back and forth a little bit. It’s not really a huge deal, but I sort of have to fight it when I ride this bike.

I could also describe it as the handling changing depending on how much I turn the bars. Sort of like it’s very stable/untwitchy at shallow angles, and really twitchy as the angle is increased.

I’m not sure if this is:

  1. normal for a bike with geometry like this
  2. a result of switching to narrower drop bars
  3. something that could possibly be corrected with a fork that has shallower rake

Any suggestions?

Your hands and body weight are much farther forward over the front wheel. I would suspect this. Messing around with aerobars on a road bike you can really feel this effect.

hmm that makes sense. maybe I’ll try a shorter stem. it’s a single bolt quill stem though so I have to untape everything ><

Try getting the bars closer to saddle height too. Since it’s a quill maybe just raise em up that way.

They’re already ~level. I’ll try raising it all the way up though and see what happens.

Good idea, it should effectively shorten the stem/bar reach relative to the wheel just like a shorter stem.

Sounds kinda like the effect when you put a too long fork on a bike, -> too slack head angle. A '84 Stumpjumper will likely have quite a slack head angle, and when you put more weight farther away on the stem (drop bar) it’ll do that. Sorta like a pendulum effect, the heavy bars and heavy front wheel swiveling around too far forwards on the headset, if you get what I mean. Shorter stem will probably help (less of leverage, kinda), or maybe even a shorter fork or one with less rake.

Just my .02 based on building frankenbikes like that.

could also maybe be an indexed headset?

Could be George W. Bush’s fault.