Choosing Gravel Bike dilemma

[T4tomo]

Stem length is a red herring. You don't steer a bike by holding it's stem, you steer it from whatever hand hold position you choose (or have to use with flats) on the bars. The amount of percieved responsiveness or control depends on how long the lever is from the steering axis to the hand grip position.
Think of bars and stem as being like two sides of a right angled triangle. The stem length determines how long the shortest side is. The width of the bars determines the second side length. The length of the actual steering lever, the hypotenuse, is the resulting product of both.

you obviously weren't top of the geometry class. if the stem length was zero mm, then a 1mm move in the bars produces exactly the same on the steerer/wheel, i.e direct steering. For increasing stem length the same movement of the bars produces a proportionally smaller movement in the steerer, as the bars are moving around an increased sized circle.

A bit wonky, but you get the drift...

 

[matticus]

The answer is somewhere between your 2 answers: but I reckon SDJ is much closer, because bar-widths are all much bigger distances than stem length.

I can't be bothered to draw some To-Scale sketches to prove this, it's only an internet forum ... :P

 

[ClichéGuevara]

The answer is somewhere between your 2 answers: but I reckon SDJ is much closer, because bar-widths are all much bigger distances than stem length.

I can't be bothered to draw some To-Scale sketches to prove this, it's only an internet forum ... :P

Isn't it academic anyway, as most steering is done by leaning rather than pushing/pulling handlebars. They're more just there to fasten the brakes to. Try riding a trike and you'll see how much different it feels.

 

[T4tomo]

The answer is somewhere between your 2 answers: but I reckon SDJ is much closer, because bar-widths are all much bigger distances than stem length.

I can't be bothered to draw some To-Scale sketches to prove this, it's only an internet forum ... :P

Too true, but bar width is irrelevant, a 10mm movement of the bar end of the stem is the same 10mm regardless of how much bar is sticking out of the side, and it turns the steerer thru a larger angle on a shorter stem. The maths don't lie!

that said, most of the steering input on a bike is from subtle leaning.....

 

[matticus]

Isn't it academic anyway, as most steering is done by leaning rather than pushing/pulling handlebars. They're more just there to fasten the brakes to. Try riding a trike and you'll see how much different it feels.

Tried it, rode into a bush. Didn't have time to learn properly, hopefully someone will bequeath one to me ...

The yang of that is to try riding a bike with a welded-up headset.

 

[SkipdiverJohn]

you obviously weren't top of the geometry class. if the stem length was zero mm, then a 1mm move in the bars produces exactly the same on the steerer/wheel, i.e direct steering. For increasing stem length the same movement of the bars produces a proportionally smaller movement in the steerer, as the bars are moving around an increased sized circle.

A bit wonky, but you get the drift...

View attachment 588317

Take a 100mm stem and a 420mm wide bar vs a 90mm stem and a 420mm wide bar. The longer stem + the bars has an effective steering lever length of 23.26 cm. The shorter stem + bars has an effective lever length of 22.85 cm. The difference is only 0.41 of the amount the stem was shortened by. You could achieve the same outcome in steering having the 100mm stem but narrower bars! In this case the reach would be longer and the grip width narrower, but the steering lever ratio would be the same.
The point I am making is the control/responsiveness of a bike's steering is down to the effective lever length, irrespective of how it is arrived at.

 

[mustang1]

I'm the kinda guy who prefers least hassle and for that reason I'd go with Fuji. But I'm also a guy who likes to buy what he like, so the Cannondale.

But out of the two, i still prefer less hassle, and so would opt for Fuji.

 

[battered]

Were the saddle height and setback the same on both bikes? If not you may be surprised how different that will make each feel and could definitely influence your conclusion of "something was not right". You may not actually need to change the stem at all, it could we be you just need the bike set up correctly interms of fitting.

This is a very valid observation. I recently readjusted my road bike, which I always felt was rather stretched out. With the saddle 1cm forward and levelled, and the bars tipped back a few mm, it felt like a different bike. I think I still have some fiddling to do as the pedals now feel further back (because they are), but it means that my proposal of shortening the stem is probably unnecessary.

 

[yo vanilla]

I'm the kinda guy who prefers least hassle and for that reason I'd go with Fuji. But I'm also a guy who likes to buy what he like, so the Cannondale.

But out of the two, i still prefer less hassle, and so would opt for Fuji.

 

[kingspirit]

Those two are quite close interms of bike fit, yes the Cannondale is slightly longer and lower interms of reach and drop, but fit a 1cm shorter stem compared to the Fuji and a minor reposition of the shifter and the reach will be very close, slightly lower but still conservative.

Fuji Jari 1.1
Stack 581
Reach 372
Top tube 550
Seat tube angle 73

Cannondale Topstone 1
Stack 579
Reach 385
Top tube 561
Seat tube angle 73.1
View attachment 588313

View attachment 588314

View attachment 588315

Were the saddle height and setback the same on both bikes? If not you may be surprised how different that will make each feel and could definitely influence your conclusion of "something was not right". You may not actually need to change the stem at all, it could we be you just need the bike set up correctly interms of fitting.

Thanks a lot, how did u do that gif picture? Which size did u use to replicate and compare the geometries?

 

[Paul_Smith SRCC]

Thanks a lot, how did u do that gif picture? Which size did u use to replicate and compare the geometries?

As you referenced 'Medium' for both the Fuji Jari 1.1 and the Cannondale Topstone 1 in your opening post that's the size I used to compose each in BikeCAD. The Pro version of that software I use has a 'morphing feature' that I can then upload to the forum so you could see the transition from one to the other, I used the same saddle height and setback; but I thought you may like to see the difference between 'reach' and 'drop' to the bars morphing between each.

If you enjoy some free technology you could draw your current bike on their BikeCAD free version; if that appeals before you do anything create your free account so that you can save your drawing when finished. You can start with either their quick start drawing, or any from their design archive ( I have just added a copy of the Topstone for you, note it is not the same bike fit as my earlier post, I did that from home where as I did this post quickly in my break at work on a different computer). Whatever drawing you start with in each case you can edit and save to your free account as your own drawing and keep it 'private' or make 'public' as desired. When you have found the drawing you want to start with simply click on the green "open in BikeCAD' tab, note as they correctly state "it can take several minutes to load". Although the free version as you'd expect offers less than their Pro Version if you draw up your current bike you may find it of use.

Normally the free version works best if you do not display the chain and rear derailleur, plus even though technically you can I would not try and upload any brand logos as it is inclined to crash; adding text to frame and components as I have done in the example above is not a problem. I have a few tips on my own BikeCAD blog that may help, there is also quite a lot of useful Videos they publish on youtube

 

[kingspirit]

As you referenced 'Medium' for both the Fuji Jari 1.1 and the Cannondale Topstone 1 in your opening post that's the size I used to compose each in BikeCAD. The Pro version of that software I use has a 'morphing feature' that I can then upload to the forum so you could see the transition from one to the other, I used the same saddle height and setback; but I thought you may like to see the difference between 'reach' and 'drop' to the bars morphing between each.

If you enjoy some free technology you could draw your current bike on their BikeCAD free version; if that appeals before you do anything create your free account so that you can save your drawing when finished. You can start with either their quick start drawing, or any from their design archive ( I have just added a copy of the Topstone for you, note it is not the same bike fit as my earlier post, I did that from home where as I did this post quickly in my break at work on a different computer). Whatever drawing you start with in each case you can edit and save to your free account as your own drawing and keep it 'private' or make 'public' as desired. When you have found the drawing you want to start with simply click on the green "open in BikeCAD' tab, note as they correctly state "it can take several minutes to load". Although the free version as you'd expect offers less than their Pro Version if you draw up your current bike you may find it of use.

Normally the free version works best if you do not display the chain and rear derailleur, plus even though technically you can I would not try and upload any brand logos as it is inclined to crash; adding text to frame and components as I have done in the example above is not a problem. I have a few tips on my own BikeCAD blog that may help, there is also quite a lot of useful Videos they publish on youtube

Thanks !