...I'll probably do 70% road and 30% gravel, with overnight trips here and there.. I like the Topstone 4, but not sure if having a single crank (idk if thats the right word) will be an issue if I'm doing more road/hard packed than I am gravel. . I'm certainly not looking for a hard charger/I don't see myself doing frequent 50 mile rides.
Yes the
Topstone 4 has a single 40t chainring with 11/48 sprockets; in old money using a traditional gear chart that equates to a
98" top gear, you will get higher on many of the other bikes you are considering that are set up with compact 50/34 chainrings and 11t small sprocket double as standard (123").
If referencing ratios as a number like that means little then in attempt to put it into context
for me that 98" gear would be enough, my
Van Nicholas Yukon Audax bike has even lower at 96" and I made quite a bit of effort achieving that ratio; in 2007 when I built the bike it was not easy to achieve that off the peg. I use that bike for
day rides,
holidays and
longer distance tours, the first two are similar to what you have potentially referenced interms of road riding and where I have interpreted where your concerns about the gear ratios of the Topstone are? For me that 96" highest gear is easily high enough for a mid 20-25 mph work out and the occasional mad half hour when I pretend to be fabulous! The only time I find it not high enough is fast mountain descents and on those occasions I am normally freewheeling admiring the view far more than trying to get my ear as close to the ground around every hairpin. I grew up riding a very traditional 52/42, 13t sprocket 108" gear and seldom needed that outside of racing so for me 50/34, 11t sprocket 123" would be something I would not desire. The Topstone has a low gear that's close to my Yukon as well, 23" is walking speed low and why I have similar, I used to
work supported tours and if anyone got off their bike to walk I could cycle next to them; I seldom need that low for my normal rides but I still quite like it as a reassuring comfort blanket. In conclusion regarding gear ratios
for me those are a good choice even on a road bike. Note I have highlighted
for me, gear ratio preferences are personal to each rider, in this instance another may desire higher or lower than the Topstone offers; you just need to work out what it is you desire and then work out the spec' you need to achieve it.
As you want to ride "70% road and 30% gravel, with overnight trips here and there" the
Topstone range would be my choice, the
Optimo range are aimed more at day rides on roads, the Topstone can carry luggage easier as well as handle that 30% gravel more effectively. The
Synapse range falls somewhere between those two, the
Sora Spec' would for me be quite viable for this role but as you move into the higher end models the range does morph more into a performance road bike and losses some of the versatility that the Sora spec' offers; capacity to carry luggage in the same way for example. For me the Topstone will do the day ride with no luggage role well enough, where as the
Optimo range will start to struggle with the Gravel and luggage carrying for overnight stops. The Cannondale Synapse Sora will do the overnight stops well enough, but factoring in the 30% Gravel I'd still be recommending the Topstone slightly more; it would be quite close mind you.
For sure to an extent 'a bike is a bike'; the Cannondale
Optimo and
Synapse ranges you referenced may not be set up as Gravel bikes and neither is my Yukon, but that's not to say on occasion I haven't used it as one;
'this pic'' was taken on
Bordeaux to Barcelona, a tour I have done three times and every time when I get to that section of about 45 minutes of Gravel I take it instead of the tarmac route; then breathe a sigh of relief when I get through without mishap; note that was near tour end, if it was 'day one' I wouldn't have risked it where as 'day one' on a Gravel style bike I would have. As I don't need a bike that would do 30% Gravel the
Sora Spec' Synapse would be my closer to my Yukon.
The other bike you referenced was the
Salsa Journeyman, in reality that's their
Topstone range, in your case again as far as I am concerned that would also be a viable consideration.