I am currently riding a Giant Defy with rim brakes. I have no complaints about the bike and it fits me well. As my riding and fitness continues to improve, I am spending more and more time in the saddle, which leads to the inevitable thoughts of upgrades. I have read lots about how upgrading the wheels on a bike make a huge improvement and I know that wheels on my Defy are entry level, so that is one angle I am looking at. Nothing crazy, but maybe a $500 set of wheels and keep the stock wheels for winter/training use. Option B is to upgrade the entire bike. My LBS will give me a great deal on a 2016 Roubaix SL4 Sport which puts my into a similar spec'ed bike to my Defy but with a carbon frame versus aluminum. Does one scenario make more sense than the other?

My first piece of advice would be that if you're enjoying the bike, and it's meeting your needs, there is no need for an upgrade.

Wheels do make a significant improvement, but not in ways you'd expect. Sure, lighter wheels accelerate faster, but that rotational inertia only applies to changes in momentum, so you don't get the compounding improvement to help you get up hills. Where they'll help the most is comfort. Wider rims and wider tires will let you run lower pressures, which greatly improves comfort and makes a marginal improvement in rolling resistance.

However, sometimes a new bike gives you a big boost in motivation, which is the best improvement of all. If your state of mind tells you to ride more and work harder, you'll make the most improvements to what matters most, the human-engine. You don't need a new bike to motivate you, though.

If you are happy with the contact points - bars, stem, saddle, post, bar tape, pedals, shoes, then I'd look at tires.

What tires are you running? New tires and latex tubes can make as big, or bigger difference than wheels.

That said, wheels are never a bad upgrade, and it's always nice to have two sets.

Yes, first be sure you are using the best tires you can. Will take some research

I would agree as long as you point out the "big" or "bigger" difference is actually a "tiny'" or "less tiny" difference.

The tires and tubes are Giant OEM stuff, 700x25cc. I'm sure there is better out there but these have served their purpose. I am about 225lbs so super lightweight wheels wouldn't work, was thinking something with better hubs and maybe a bit stiffer though.

It's always good to have a second set of wheels.

Hmm. So you haven't even ridden enough to wear out a set of tires yet? I would say wait until you actually wear something out on your current bike before upgrading. Buy yourself a new jersey or some gloves. As for better hubs, I doubt you will notice any performance difference. At your current weight, it only makes sense to upgrade wheels if your current wheels are giving you trouble.

Figure out what aspect of your current setup you would like to improve. Figure out what piece of equipment will fulfill that. If just looking to spend some money, how about a flashy jersey or something.

I suppose that is part of it.

A 2nd set of wheels is a good investment and will continue to serve you well even if you upgrade bikes later.
That said, stock Giant wheels are actually decent wheels, so you might be even better served to drop a few dollars on a fast set of tires. That can make a BIG difference in speed and handling.

Whatever you do, don't try to do too many upgrades too soon. If you really do take to cycling, your ideas about what kind of bike and gear you want may change two or three times in the next year or two. You don't want to spend all your money on a great touring bike only to discover you're really a CX racer at heart. By the end of the summer you'll have a much better idea of what you like and don't like on your current setup and won't need us to tell you where you should spend your upgrade bucks.

Why make it easier if you are trying to improve your fitness and stamina? That's like flying to London and parachuting out midway.


Anybody can tell you to spend money. Spend time and earn fitness. By the time you get there that stuff will be on sale.

My least favorite argument. Why shouldn't someone have the bike they most enjoy riding? I know I wouldn't ride nearly the hours I do if I didn't have a fast bike that gave me a thrill every time I hopped on. The investment also provides some incentive to get out there on days when the weather is bad or I'm not feeling 100%.

BB

Start with a set of Conti GP4000s in 25mm....and ride more.

I concur with the tires

I don't see a problem with no wheel or new bike, not don't expect they will make you a (much) faster (better) rider. Upgrading equipment is part of the fun of bike ownership.

Between a new wheel or new bike, if the currently bike is working well for you, I would go with new wheel. something different than what you already have so you have option for different rides.

To qualify, I'm not a total noob to cycling. I rode mountain bikes for years and a couple years ago I bought I gravel bike which I use to commute with and do gravel rides as I live on the edge of the city, so lots of rural roads to explore. Up until recently, I would categorize my rides leisurely as I only pushed myself as hard as a felt I wanted.

I've since joined a cycling club, mainly to improve my fitness level and improve my riding. I feel both are being accomplished. I bought the Defy because it was a decent bike and I figured for the price, if riding in a group wasn't my thing, I wouldn't take a bath if I decided to just go back to riding my gravel bike full time.

I think I've past that line in the sand, so now I just want to make sure I'm not bringing a knife to a gun fight, so-to-speak. I'm not really prepared at present to $4-5k on a carbon bike, but I don't mind spending some extra to either upgrade my Defy or maybe move to the next tier.

+1
I would even go for 28mm GP4000s if you have clearance for them.

You're not. Get some nice tires and replace your wheelset and/or frame when what you have is no longer cutting it for you and you can articulate why it's no longer cutting it for you.

Sounds good. I appreciate the advice.

From reading your comment above & making some assumptions, I'd keep what you have for a while w/o upgrading and see if you really are hooked on cycling. If so, get the $4-5k bike - if not, you didn't lose anything. I'm afraid you may be the type (like me) that just keeps upgrading until you get the best/really good quality. Those middle steps can get expensive.

A Defy will serve you just fine. Do concur with others about tires, fairly cheap upgrade and does make a good difference. Lacks the bling factor though.

The problem with upgrading to a different bike? You will soon want to upgrade the rims on it. So I would get the rims ride the bike you have then down road move them over to a new bike.

This is actually what I'm doing this year. The bike that I want comes with wheels that I'd want to upgrade pretty much immediately, which would be a bit of an economic stretch, so I decided to get the wheelset now and the bike at the end of the season or even at the start of the season next year.

I'm not really a latest & greatest kind of guy with anything. Once I find something I really like, I keep it for a long time. It just sometimes takes bit of time and effort to settle into that equilibrium. Maybe I will start with some tires and progress from there. I would like to try some 28c tires to see how they work.

A bike is a combination between a nice toy and a "device" used to increase fitness for various purposes. I think that one should buy the most fancy bike he likes, within his available budget. So, if you like Roubaix, go for it. It looks to be a very good bike and Shimano 105 is meant to last for a long time. Carbon fiber is very nice to ride. However, carbon is sensible and you should get used to thrill at every strange noise made by the bike, since it can indicate a failure in carbon fiber (although in the vast majority of cases, it proves not to be the case).