My current bicycle frames geometry is in some way different from my previous.
When I first tried it, barebone (the bike not me), after acquirement, it felt very "nervous", it was hard to ride straight / control it. To the point that it felt unsafe.
I first thought the tire (27.5", 62-584) pressure was at 2.5 bar too low (it was, for my weight) but an increase to 3 bar and beyond didn't make it better.
I spend a week riding it like that, and the last day felt as uncomfortable as the first.
Then, I started to fit the bike to my needs, first double bags hanging over the rear rack. Again a week later, a basket on top of the rear rack. Shortly after, I had no free space avail in the bags, and I put about 3 kilo luggage in the basket.
Big surprise: the "nervous" feeling was all of sudden completely gone from that very moment (leaving a market).
Flashforward 2 years to present day, couple days I discovered several bolts of the rear rack being loosened / lost. I had to completely dismount my luggage gear in order to reach some bolt locations. In meantime, before putting it all back, I made a ride, didn't think of it, but it reminded me: that "nervous" bike response was back in all its glory.
And gain gone after refitting.
Clearly, the bikes geometry must have a flaw somewhere. But it's hard to pinpoint.
Since filled bags under the rear rack didn't make a difference, but filled basket above does, it seems like vertical weight center related.
Ex a boat with a high sitting weight center, rolls easier, and is more stable with a lower weight center. But this bikes case is the opposite.
I always have a couple backpacks, a couple waterproof bags and an aluminium mountain trek frame mounted above my rear rack, so this is an everyday solution to the problem.
But what can be wrong with the geometry to cause this?
When I first tried it, barebone (the bike not me), after acquirement, it felt very "nervous", it was hard to ride straight / control it. To the point that it felt unsafe.
I first thought the tire (27.5", 62-584) pressure was at 2.5 bar too low (it was, for my weight) but an increase to 3 bar and beyond didn't make it better.
I spend a week riding it like that, and the last day felt as uncomfortable as the first.
Then, I started to fit the bike to my needs, first double bags hanging over the rear rack. Again a week later, a basket on top of the rear rack. Shortly after, I had no free space avail in the bags, and I put about 3 kilo luggage in the basket.
Big surprise: the "nervous" feeling was all of sudden completely gone from that very moment (leaving a market).
Flashforward 2 years to present day, couple days I discovered several bolts of the rear rack being loosened / lost. I had to completely dismount my luggage gear in order to reach some bolt locations. In meantime, before putting it all back, I made a ride, didn't think of it, but it reminded me: that "nervous" bike response was back in all its glory.
And gain gone after refitting.
Clearly, the bikes geometry must have a flaw somewhere. But it's hard to pinpoint.
Since filled bags under the rear rack didn't make a difference, but filled basket above does, it seems like vertical weight center related.
Ex a boat with a high sitting weight center, rolls easier, and is more stable with a lower weight center. But this bikes case is the opposite.
I always have a couple backpacks, a couple waterproof bags and an aluminium mountain trek frame mounted above my rear rack, so this is an everyday solution to the problem.
But what can be wrong with the geometry to cause this?