New aero bike: Cannondale SystemSix vs Giant Propel

I have the chance to buy either a 2021 Cannondale SystemSix Ultegra, or a Giant Propel Advanced Pro 1 Disc.

Here is the SystemSix:

Here is the Propel: Propel Advanced Pro 1 Disc (2021) | Giant Bicycles UK

Both are within budget, but the Giant is £1,000 less than the SystemSix, and comes with a dual sided power meter. That said, the SystemSix is said to be faster and more comfortable. It’s also, in my opinion, a much better looking bike. The Propel’s stem is just plain bad looking.

I currently have a super light Trek Emonda SLR which is my pure climbing bike, and I’ve been wanting an aero bike for some time as my second ride.

My usual rides are 100k group rides on rolling roads, with good climbs no longer than 15-20 minutes and plenty of fast sections.

I will be testing both bikes in the coming days, but would be very grateful to hear everyone’s thoughts. Cheers!

You already said what I was gonna say……they are both great bikes, but man, at some point I would reach the point where riding the Giant would not excite me. That stem design is just butt-ass ugly.

£1000 is no small chunk of change, but having a bike that appeals to you is important, too.


I have a system six and absolutely love it - great bike. Not sure I can give you advice on which to buy since the cost difference is so large and your personal finances are, well, personal

That said - if you buy a bike that you don’t like the looks of you’re probably going to regret it eventually. Maybe not this year, but eventually you’re going to wish you’d gotten something you truly loved.

In most situations I recommend saving up to buy the item you really want rather than buying what you can afford now just to have it sooner


This. I worry that if I get the Giant, I’ll always look at the SystemSix longingly. Whereas I won’t “miss” the extra money per se. I imagine I’ll be too busy enjoying my gorgeous new bike.

1 Like

Another vote for the Systemsix here, I just built up a ‘non Hi-Mod’ frame and I love it. While I wouldn’t call it comfortable, it’s not bad at all, and it certainly looks fast (I’m sure it actually is as well!). I also have a Supersix and can barely tell the difference on climbs FWIW. Ultegra is a great groupset, and you’re getting some decent aero wheels and integration as well in that build. If you like how it looks, you’ll ride it!

Having said all of that, I hear great things about Giant bikes and long lusted after a TCR, so looks aside it would be a good choice as well.

1 Like

Am I the only one that likes the Propel’s stem haha? To me it looks cool but everybody has their preference.

1 Like

Systemsix if u like dropping ur mates. I have one, and love it!!!

1 Like

Buy once
Cry once

Buy the bike you like the most


I bought a Propel Advanced SL0 last year, since then it’s become my favorite bike for everything that isn’t an alpine climbing ride. It’s very comfortable for 200km rides, great in crits and rolling road races. Highly recommend one.


The longer I have my propel the better looking I think the stem becomes…I can’t comment of the comfort of the cannondale but I have no issues with the propel outdoors (on the trainer it’s a different thing)

1 Like

See which wins the most races on the World Tour… :wink:

1 Like

@Bagz :joy: #science

1 Like

I also really like the look of the stem… but me and my private parts think it’s terrifying :grimacing:


I have the System Six Hi Mod Ultegra (2019 version) and love the bike. The only thing I would check with before pulling the trigger is what size tires you can run, as clearance on the rear wheel is tight.