elbetzzz

Hey, I bought a 2018 specialized diverge e5, a few weeks ago . It is the cheapest model, with Claris gear set.
I bought it mostly because the geometry is really comfortable for me, I can spend more time riding it, than on 100% dedicated bike (I used to ride an old Cannondale caad3 -r600)
I ride it on the road 95% of the time so, the off-road capabilities aren't really too important for me. The comfort is great, It really seems to fit me perfectly, also, disk breaks are really good for Mexico City's weather, and constantly stop and go riding conditions (due to traffic). But, I really miss the speed and agility of my old Cannondale.

I'm thinking of replacing the chainrings for bigger ones and mounting some thinner tires, so I'm looking for some suggestions. Any ideas?

will the Axis Sport Disc wheels hold 700x25 tires? is it a good idea to put some 50-36 chainrings, instead of the stock 46-34?

Hope you guys can help

alcjphil

You may be confusing agility with speed. Yes, a road racing geometry bike will be more agile, but it won't necessarily be faster. As for tires, the 700 x 30 tires on your bike probably don't have more rolling resistance than a 700 x 25 tire of the same construction and quality. The bigger tire will be heavier, but all that means is that it will be a bit more difficult to accelerate, not that you will be able to ride at steady speeds faster with a tire that is only 5 mm narrower. Gearing? I raced for years on a bike that had a 48 tooth big ring. Even with only 48 teeth, I seldom had to use my highest cassette cog to keep up in a race, when speeds could go well above 50 kph. Your new bike is quite different than your old one. Have you been able to compare your speeds on routes that you have done on both bikes? My guess is that you probably are not riding any slower than you did before. Correct me if I am wrong. Your new bike is the type that makes faster speeds seem slower than they are

wphamilton

Specialized claims that the Espoir Sport, 60 TPI tires have "low rolling resistance" but I have a hard time believing it.

CAT7RDR

Looks like a sweet urban bike with nice gearing for climbs.

I would Not change a thing and ride it until you wear out tires and components. If you then change your mind, you can always upgrade or make it more to your riding style.

johnny99

How heavy are the stock tires? Even if you stick with the current size, higher-end tires may be much lighter weight, which will be noticeable when you accelerate (which is often in stop-and-go traffic). Also think about your handlebar position. Adjusting the handlebar height or reach can make your bike more responsive (depending on your body shape and riding style, etc).

Campag4life

With 95% of your time on the road, sell it an buy a lighter and higher performance Trek Emonda with H2 geometry that you can replicate your position on. A 15 lb bike versus an almost 20 lb bike. The Diverge with FS is a heavy bike and you spending virtually all you time on the road versus off, why own a bike to slow you down. An endurance road bike...not the FS Roubaix which is also a heavy bike...is more efficient for spirited riding on pavement with friendly geometry.

pdoege

What kind of speed are you looking for? You can purchase a FC-2000 with 50-34 for ~$60US.

Homebrew01

Wind resistance is a major barrier to "speed". A more aerodynamic position will allow you to go faster. Gearing is very rarely a limiter.

Lighter wheels and tires may feel livlier and make a small difference.

elbetzzz

yeah, I already compared both bikes speeds on the same riding conditions and it is actually 2 or 3 seconds slower than the old Cannondale, on the same routes (I always do commuting using the same roads, so it is easy to keep record) exactly as you say, it is more difficult to accelerate than with the old bike, I'm guessing it is due to the huge difference on both bike's components and main purposes. But, I notice it even more, when I go to closed roads, like racetracks... I'm not a high-performance racer, but I used to be able to keep up with most of the groups of semi-pro bikers that usually go there for training, at least for a few laps. That's why I was wondering if any light mods on the diverge, would help to keep the comfort of the geometry and position intact while gaining some speed when needed.

Anyways, I love the new bike and intend to keep it. It is tougher than a 100% road bike, and that is a great feature, given the road conditions here in CDMX. Also bought the cheapest model, thinking on possible further upgrades and mods...

elbetzzz

not sure how much does the stock tires weight, but that is actually a good thing to dig on... Maybe getting 28mm continental Grand Prix tires, or something similar can help lowering the weight?

McBTC

Good tires but-- look for a good buy on Vittoria's Rubino G... I'd have 28s all-around but can't fit more than a 25 on the rear of my rig. Love a 28 on the front tho...

HTupolev

A 28mm GP4000SII would definitely lower the weight (30mm Espoir Sports are over 400g each), but the biggest gain from a good performance-oriented tire would likely be lower rolling resistance.

nymtber

The 700x30c Espoir Sport only weigh a svelte 435g, too!

DrIsotope

Replace. Those. Tires.

I'm not kidding. The Espoir Sport has minimal flat protection, and is basically like the OEM tire that comes on the cheapest import car money can buy-- they are under $12 each invoice.

Shame they fit the bike with a decent wheelset but garbage tires.

Mark VerMurlen

TrojanHorse

use the diverge for city riding and set up your cannondale for track riding. Boom, done.

aclinjury

About "rolling resistance" vs "air resistance". Sure, a 30mm tire might not have a worse rolling resistance than say a 25mm tire. But, at higher speed, say 18+ mph (28 kph), then air resistance becomes more dominant, and MUCH more dominant the higher the speed. So to grade a tire's performance solely on "rolling resistance" is an incomplete picture. I've read many mentioning that in order to have the optimal air resistance profile, the tire (when fully inflated to riding PSI) should be just about a tad narrower than the width of the rim as this will give the most optimal airflow laminar. Chances are, a 30mm tire sitting on your rim right now give the wheel that overall "bulbous" profile, and this bulbous profile will slow you down as the speed goes up significantly. Remember air resistance increase as the square of speed, where as rolling resistance does not. In fact a narrow tire with worse rolling resistance at low speed can end up being faster at higher speed as air resistance becomes dominant factor.

Abe_Froman

All true from everything i've read. Has anyone seen actual data on how much a larger tire affects aerodynamics? It seems a bit hard to come by. I'm wheel shopping now and a bit overwhelmed by all the size options lol.

topflightpro

Put some decent tires on there first. You don't need a different bike to go faster. But tires will help a lot.

If you start spinning out your gearing (unlikely except going down hill), then consider different gearing. But for now, new, quality tires, will help a ton.

Zombiesloth79

superpletch

tire and wheel upgrade is the most effective. a few grams per wheel/tire will make a big difference. slightly aero wheel which is tubeless with a good light tire with low rolling resistance will make it seem like a different bike.

aclinjury

I have not seen any rigorous experiment that would test a wide combination of tire sizes vs. rim width. But let's take the Zipp 404 Firecrest as an example. It has a 25mm wide brake track. Zipp recommends to use a 23mm wide tire at the front for the best combination of "aerodynamics" and "rolling resistance". For the rear, Zipp recommends using 25mm tire. Most likely the reason for this sort of 23/25mm recommendation is that airflow laminar is much more important for the front wheel then is for the rear wheel. The front wheel is the first part of your bike that hits the wind so airflow needs to be maximized and given a higher order of important than rolling resistance. The rear wheel is less important for aero thus Zipp recommends to go with 25mm tire for a bit better rolling resistance and comfort.

If you're currently looking for a wheelset, then go with "wide" wheel, as wide as your bike can fit them. Many of the latest generation wheelset have their brake track at 25mm wide or more, and some even get as wide as 28mm! Then slap some 25mm tires on them. If you plan to use 25mm tires (which is all the current rage due to "comfort"), then I'd go with 28mm wide rims IF your frame fits this combo. Otherwise, 25mm wide rim with 25mm wide tire is ok too, but 25mm rim will be best with 23mm tire if aerodynamics is a high priority for you. Personally, I'd with go with a 25mm rim w/ 25mm tire combo as this will give you the best of aero, rolling resistance, and frame fit compatibility.

Psychocycles

You mentioned that you are comfortable with the bike set up as it is - have you tried to slam the stem, or at least drop it a space or two? You can work you way down so that you're only slightly out of your comfort range until your handlebars are nice and low, which will help with the aero side of things.

winston63 

Just picked up a couple of these in 28 to try on my Diverge. I’ve got a similar bike as the OP (Diverge E5 Comp) which I’ve only owned for a couple of months.

The Comp has 105 instead of Tiagra and few other differences (has futureshock) but is still Aluminum framed and comes equipped with the same 30 mm Espoir Sport tires. I won’t get a chance to mount the new rubber for a few days but I’m looking forward to trying these out.

All that said, I really do enjoy the ride of the bike. It’s not as responsive as my Scott, but it’s plenty comfortable and incredibly versatile.

Dean V

Just put some Conti GP4000 28mm tyres on it. This talk of aero wheels, lightweight wheels etc is a bit much for what you are doing.