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Custom Specialized S-Works Tarmac SL7 staff race bike: Which parts would you switch out?

As the race season fast approaches we take a closer look at Jamie's custom-built Tarmac SL7

The Specialized S-Works Tarmac SL7 is a do-it-all carbon road race bike, balancing lightweight and aero credentials, and it's my frame of choice for this 6.92kg build. I'll be the first one to admit that a few of my component choices are a little abstract, so let me know which components you reckon I should switch out before the 2023 race season starts in the comments section below...

2022 S-Works Tarmac jamie's bike

> Review: Specialized S-Works Tarmac SL7 Dura-Ace Di2 2021

Kicking off with the frame, this is a 2022 colourway of the Specialized S-Works Tarmac SL7 in a size 54cm. When deciding on frame colour, I was tempted certainly tempted by the black raw carbon as the minimalist paint scheme is by far the lightest (and paint can add quite a few grams to a frame!) As it was I opted for the Fluid/Satin Black, in some lights, it shows purple hues, in others greeny/blue, and on a dull day )i.e most of them in the UK) a more understated grey.

2023 Specialized Sl7 tarmac jamie custom build bars

One of the Tarmac's highlights for me is the integration. While I'm not a fan of many fully integrated bikes, I do have a soft spot for race bikes with hidden hoses; not necessarily for the alleged aero benefit, but more so for the cleaner lines.

The system on the Tarmac hides the hoses through the 40cm Roval Rapide bars, using further guides to keep them hidden as they then travel under the stem (130mm/-12).

This also means that the stem can easily be removed, excellent for maintenance and travel. A Wahoo Elemnt Roam is up front with a second quarter-turn mount underneath for a front safety light. My setup is finished off with a titanium top cap and bolt from God and Famous. If you haven't heard of them before then check out some of their very wacky bar tapes and accessories.

2023 Specialized Sl7 tarmac jamie custom top cap

> Review: Roval Rapide CLX

Moving down the bike and you'll find that despite testing 10's of wheelsets since, I'm still a firm fan of the Roval Rapide CLX I wheels. They're stonkingly fast, super wide and stable in crosswinds. They haven't been trouble-free though, and thanks to a rock strike on the front wheel I will now only use them with tyres at least 28mm wide.

2023 Specialized Sl7 tarmac jamie custom build roval

Review: Vittoria Corsa Fold G2.0 tyre

As these are the first generation of Rapide wheels they are NOT rated by Specialized for tubeless use (although I have seen people doing it) I use Silca Competition Latex tubes which come with these funky 'Speed shields' as shown below. Are they more aero? Apparently, but that's near impossible for us to test. What I can say is that they do stop any unwanted valve stem rattle which is very welcome.

As you may have heard me hark on about, I'm a big fan of the Vittoria Corsa Graphene 2.0 tyres. They grip like nobody's business and thanks to a high TPI count are about as supple as clincher tyres come. The 2.0 version also seems to have fixed the tread peeling problem that I repeatedly suffered with the previous generation. 

2023 Specialized Sl7 tarmac jamie custom build tyres

The main bulk of the groupset is Shimano Ultegra R8070 Di2, well the shifters and mechs are anyway. I've had these for some time so they've seen a bit of a battering, however this 11-speed groupset still performs perfectly despite missing out on that extra cog of the latest generation of groupsets. 

I haven't done the maths of how many grams I could save by switching components out to Dura-Ace, but I reckon as the components with the greatest difference such as cranks and brake callipers are aftermarket anyway we're talking in the region of about 150g, not worth it if you ask me!

2023 Specialized Sl7 tarmac jamie custom build cranks

> 12 reasons why you should buy, and use, a power meter

Some of those aftermarket parts include the drivetrain, the crankset is a 170mm Quarq carbon DFOUR DUB affair with 52/36T Dura-Ace chainrings and a YBN SL110 chain, because best bikes should always have a bit of bling and YBN chains always appear to perform well in independent wear testing.

One thing to note is that where the Quarq power spider (which remains in my eyes the benchmark for power meters) attaches to the crank arms using Sram's eight-bolt system there is a tendency for creaking. It took me a long time to diagnose this and was only solved with a healthy dose of Loctite. Let's hope I don't need to get it off on a hurry!

2023 Specialized Sl7 tarmac jamie custom build cranks Quarq

I've also switched out the jockey wheels to the uprated Dura-Ace ones. These run on actual bearings rather than bushings like Ultegra.

My pedal choice also remains in the Shimano corner. I was a long-time user of Look but despite the excellent aesthetic and performance when new, I've been turned to the SPD-SL system for the prolonged lifespan, in my opinion. For training, I tend to opt for the cheaper Ultegra pedals but for racing go Dura-Ace, not for the weight advantage or extra set of needle bearings but the reduced stack height reducing the chance of pedal strikes.

Just like on my Allez Sprint build I've switched out the temperamental Ultegra brake callipers for Magura MT8SL FM callipers. These are lighter, look better and perform admirably with the Magura hoses, Shimano shifters and Magura Royal Blood mineral oil.

2023 Specialized Sl7 tarmac jamie custom build brakes

> Check out more Staff Bikes here

What have I missed? The brake rotors are Shimano MT900 160/140mm for maximum wheel compatibility from neutral service and the saddle is subject to change. Currently on the bike is a Fizik Adaptive R3, but I've recently been using a Bjorn Setka, reportedly the world's lightest 3D saddle. The full review of that will be coming very soon.

In its current set-up the bike weighs in at a fairly competitive 6.92kg. There's a few titanium screws to help it down to that weight but which parts should I switch out? I'm always looking for new and lesser-known parts to try out so let me know down in the comments section below...

2023 Specialized Sl7 tarmac jamie custom build lights

Spec Sheet:

  • Frame: 54cm Specialized S-Works Tarmac Sl7 (Fluid/Satin Black)
  • Wheels: Roval Rapide CLX I
  • Tyres: Vittoria Corsa G2.0 28mm
  • Inner tubes: Silca Competition Latex w/ speed shields
  • Bars: Roval Rapide 40cm
  • Stem: 130mm/-12 degree Specialized Tarmac Sl7
  • Brake Callipers: Magura MT8 SL FM
  • Brake hoses: Magura
  • Groupset (minus crankset): Shimano Ultegra Di2 R8070
  • Pulley wheels: Shimano Dura-Ace R9100
  • Cranks: Quarq DFour DUB 170mm
  • Bottom bracket: CeramicSpeed Coated DUB BSA 68mm
  • Chainrings: Shimano Dura-Ace R9100 52/36T
  • Pedals: Shimano Dura-Ace R9100
  • Saddle: Fizik Antares Adaptive Versus Evo R3
  • Chain: YBN SLA110
  • Disc Rotors: 160/140mm Shimano XTR M900
  • Bottle cages: Elite Leggero

Alternative component recommendations very welcome down in the comments section below! Which changes should I make first...?

Jamie has been riding bikes since a tender age but really caught the bug for racing and reviewing whilst studying towards a master's in Mechanical engineering at Swansea University. Having graduated, he decided he really quite liked working with bikes and is now a full-time addition to the team. When not writing about tech news or working on the Youtube channel, you can still find him racing local crits trying to cling on to his cat 2 licence...and missing every break going...

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Cyclespeed Tours | 1 year ago


a) Galfer disc rotors, same size, 160/140 so no issues changing wheels. About 90 and 75g.

b) AX Lightness or similar saddle, 75g

c) Extralite wheels, these are excellent and can be under 1kg.

With these and other tweaks my Factor Ostro (very similar to the SL7, I have a video comparing the two) is under 6kg.

Flavor | 1 year ago
1 like

how about a custom made to weight and style seatpost?

Cheers, awsome Ride!

Ans swap over the oil slick Sigeyi hanger from the Allez


Jamie Williams replied to Flavor | 1 year ago

The darimo seatpost had certainly crossed my mind... They're lovely pieces of kit but not the cheapest way of shedding some grams! A second sigeyi hangar is on order!

GT | 1 year ago
1 like

Most pics have one bottle cage ( looks like Leggero) but then one has one on the seat tube that looks like Custom Race. 

Jamie Williams replied to GT | 1 year ago

Well spotted! It is indeed the leggero, that one is my favourite bottle cage yet and then the custom race comes out in emergencies. Need to order up another leggero now there's some stock

cpark | 1 year ago
1 like

Maybe the handlebar?
I had a size 56 Sworks Tarmac that came with a 42cm bar and while the width at the drop was perfect, I felt the width at the hood was too wide.  
I switch it out for an Enve SES aerobar that I have been using for awhile and I felt right at home.   
Due to so many variables with the bar (reach, drop, and flare or no-flare), I think the bar selection needs a special attention.  
By the way, I used to work at one of the largest Sworks shops in the area, and I noticed that about 1/2 of the Swroks tarmac riders were on a flared bar. 

I also needed a -12 degree 120mm stem and I appreciated their semi-internal routing.  
Also, maybe add a chain catcher?  Dropping chain is less likely with Di2 but it can happen....
The bike does look outstanding!👍

Jamie Williams replied to cpark | 1 year ago

I certainly have considered using a flared bar as liked the set on my gravel bike, however, I've got on well with the shape of the drops on the rapide bars and I love the tidiness of the cable integration which puts me off the full brake bleed and rehose if I swap!!! 

lesterama | 1 year ago
1 like

Bike looks great. If I were in your position I would be thinking about whether to swap the frame for the next size up: marginally less aggressive, more predictable handling and hopefully fewer crashes as a result.

If it were my bike, I'd keep that bling chain and swap everything else (sorry!) for my C59 with full Etap. Not that the SL7 doesn't tempt me, I just love the look and ride quality.

Jamie Williams replied to lesterama | 1 year ago

Aha not keeping a lot then!!! But cheers for the comment, maybe I'll join the dark side of sram eTap when the new rumoured stuff launches  3

Cyclespeed Tours replied to lesterama | 1 year ago

Never heard anyone say, "bigger frame = less crashes" before.....?!

Secret_squirrel | 1 year ago

First I've ever heard of Ultegra calipers being temperamental.  Whats the issue?

Jamie Williams replied to Secret_squirrel | 1 year ago

I'm referring to the R8000 callipers which I found rubbed a fair bit after descents (This was addressed with greater clearance on the later R8100 generation), the pad retention pins get stuck for a past time although this can be solved with a Shimano XT bolt (or split pin) but the nail in the coffin for mine were hairline cracks in the ceramic pistons causing a small but very annoying leak of oil on to the pads

Fluffed replied to Jamie Williams | 1 year ago
1 like

I have that vintage brake on mine, the pad clearances are TINY. Any heat into the rotor will result in them pinging for a minute or two.

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