105 Di2 and Dura-Ace Parts Swap

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photocycler
Posts: 117
Joined: Fri Feb 01, 2013 6:19 pm
Location: Portland, Oregon

by photocycler

I'm considering buying the Tarmac SL7 Comp - Shimano 105 Di2 and want to swap some of the items like hoods/brakes and cranks for dura-ace. From what I see I can swap any Di2 part and there are not different cables or different seat post battery? Is that accurate or am I missing something?

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208
Posts: 341
Joined: Wed Apr 26, 2023 6:57 pm

by 208

photocycler wrote:
Mon Apr 08, 2024 4:50 pm
I'm considering buying the Tarmac SL7 Comp - Shimano 105 Di2 and want to swap some of the items like hoods/brakes and cranks for dura-ace. From what I see I can swap any Di2 part and there are not different cables or different seat post battery? Is that accurate or am I missing something?
Pretty sure they're all interchangeable if all 12sp, they use the same battery.

I'm running all 12sp stuff: ultegra hoods, 105 fd, ultegra rd, grx calipers, 105 crankset, diy satellite shifters, ultegra cassette, rear da da rotor, front ultegra rotor lol

OtterSpace
Posts: 397
Joined: Sun Mar 08, 2020 6:28 am
Location: California Silicon Valley

by OtterSpace

All 12s Shimano Di2 road stuff is cross compatible. Except for very rare edge cases 11s stuff is not compatible with 12s.

The hoods inner molding might be a bit different for 105 due to not having top bottons that the higher stuff has even though the outer shape is the same.

In terms of value and performace for Shimano Di2 12s:
Shifters: 105 if you dont care about servo wave top bottons or satellite shifters, Ultegra if you do. Dura-Ace shifter clamps is an ok $/g upgrade. Dura-Ace is very expensive $/g.
Calipers: 105 or Dura-Ace. 105 is the same weight as Ultegra. Dura-Ace is very nearly the lightest caliper and 1 part.
Rotors: Galfer if you can. Ultegra level if sticking Shimano. Dura-Ace level is the same weight as Ulegra level but easier to clean the glossy inner finish. 105 level have no special features so I'd look elsewhere.
Crankset: All are heavier now due to recall mittigations. Ditch the crankarms if you can but the rings are the best shifting you will get on Shimano drivetrain. You can pair Shimano chainrings with carbon crankarms such as Red D1 with adapter spiders. Ultegra chainrings are like 5g heavier than Dura-Ace and both are hollow but I've never seen photos of them failing. 105 chainrings are solid and heavier.
FD: Ultegra. 105 is previous gen tech rebadged and Ultegra isnt much more expensive and is good $/g over 105. Dura-Ace is horrible $/g. If I had a 105 bike this is the first non wear part I'd upgrade.
RD: All have their place. Use a direct mount hanger if you can. 105 is great and has the longest cage. Ultegra is decent $/g upgrade at current market rates. Dura-Ace drops more weight but is fairly expensive still but better value $/g than shifters or FD. Some people sell their Dura-Ace cages after sidegrading to OSPW and you can use those cages on other Shimano RD for a decent $/g upgrade if you are not using a 11-36 cassette.
Chain: Dura-Ace level. Better longevity and decent $/g. If your bike comes with Ultegra level wear through it but if you have 105 level I'd just bin it.
Cassette: All have their place. 105 is the only Shimano option if you need 11-36 but you are losing HG+. Ultegra is a good balance and gets you HG+. Dura-Ace cassettes offer the best $/g in all Dura-Ace level components upgrades so should be the first Dura-Ace upgrade to consider after the chain.
Battery: There is currently only one battery compatible with 12s. Due to shifter design it must be wired to rim brake shifters and due to 105 design it cannot be wired to the 105 shifters except for performing firware updates.

208
Posts: 341
Joined: Wed Apr 26, 2023 6:57 pm

by 208

Just wanna add that the rd motor is all the same across 105 ultegra da.

OtterSpace
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Location: California Silicon Valley

by OtterSpace

208 wrote:
Mon Apr 08, 2024 10:24 pm
Just wanna add that the rd motor is all the same across 105 ultegra da.
Yes performance wise the RD is the same for all 12s Shimano road options except for cage length which is a very minor optimization. Also the RD is the most likely item to be damaged cosmetically in a minor crash which is something to consider as a positive for 105 as it is the cheapest to replace and loses the least value when sold with crash damage.

K4m1k4z3
Posts: 368
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by K4m1k4z3

OtterSpace wrote:
Mon Apr 08, 2024 9:53 pm
All 12s Shimano Di2 road stuff is cross compatible. Except for very rare edge cases 11s stuff is not compatible with 12s.
RD: All have their place. Use a direct mount hanger if you can. 105 is great and has the longest cage. Ultegra is decent $/g upgrade at current market rates. Dura-Ace drops more weight but is fairly expensive still but better value $/g than shifters or FD. Some people sell their Dura-Ace cages after sidegrading to OSPW and you can use those cages on other Shimano RD for a decent $/g upgrade if you are not using a 11-36 cassette.
That's well summarized, however I have to ask if a Dura-Ace RD-R9250 cage is indeed a straight and simple swap with, say, an Ultegra RD-R8150. The cages seem a bit different - especially the main bolts. Can anyone confirm? I assume one would also use the Dura-Ace SPRING? (Since it has a different SKU from the Ultegra one.)

ULTEGRA: https://dassets.shimano.com/content/dam ... 0-4864.pdf
DURA-ACE: https://dassets.shimano.com/content/dam ... 0-4812.pdf
Attachments
Cage Ultegra.png
Cage Ultegra.png (38.19 KiB) Viewed 2152 times
Cage Dura-Ace.png
Cage Dura-Ace.png (47.39 KiB) Viewed 2152 times
'24 S-Works Tarmac SL8 RTP|Ultegra R8100|Alpinist CL / Custom Rapide CLX 2x60
'19 Diverge E5 Comp
'18 Epic HT Comp Carbon WMN
'18 TCR Adv Pro 1 Disc

OtterSpace
Posts: 397
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Location: California Silicon Valley

by OtterSpace

K4m1k4z3 wrote:
Tue Apr 09, 2024 7:40 am
That's well summarized, however I have to ask if a Dura-Ace RD-R9250 cage is indeed a straight and simple swap with, say, an Ultegra RD-R8150. The cages seem a bit different - especially the main bolts. Can anyone confirm? I assume one would also use the Dura-Ace SPRING? (Since it has a different SKU from the Ultegra one.)

ULTEGRA: https://dassets.shimano.com/content/dam ... 0-4864.pdf
DURA-ACE: https://dassets.shimano.com/content/dam ... 0-4812.pdf
Interesting catch on the spring. I saw someone else here made the swap so I never bothered looking at the service manuals myself. When OSPW users sell on their stock cage they keep the Dura-Ace spring and the P-seal ring and sell just the cage.

I made the exact swap you are asking about 5 months ago using the Dura-Ace cage assembly and the Ultegra P-Spring and P-seel ring on my RD-R8150.

Overall I'd rate the swap over as a good optimization change that is very simple to install but I wouldnt pay more than $125 pre tax for the Dura-Ace cage & jockey wheels. Also you almost certainly get better $/g going from 105 to Ultegra vs adding this to 105 so I don't think it makes much sense to do on 105 other than better color matching.
cage update.png
cage update.png (465.45 KiB) Viewed 2035 times
My order for reference on pricing. I don't see any up now but set an eBay filter for it to email you at a price you find acceptable:
order.png
Another thing to be aware of is that on a Dura-Ace RD supposedly the system will lock out small small on at least 50/34 11-34 as that drop is not supported by Shimano's teeth drop spec. If you run the Dura-Ace cage on Ultegra or 105 the system wont know to lock out this combo. Small small is way less usefull than big big but sometimes I've forgotten to move the big ring back over and am momentarily in that combo and havent run into issues but I'm on 50/34 11-30 on that bike.

Lastly I've heard the spacing, bolts, and washer assembly is different for the jockey wheels so I don't think you can easily do just a jockey wheel swap between the assemblies but I haven't bothered trying that isolated swap.

BikeTyson
Posts: 704
Joined: Fri Oct 15, 2021 3:16 pm

by BikeTyson

Just as an addition to the above post, I did the same DA cage onto an Ultegra RD. Simple swap, been running great for over 1,000 miles. I didn't change any springs. My thought is that the spring is more important to match to the RD not the cage. So I kept the Ultegra spring.

The important thing. The 105 cage is not swappable. The Ultagra and DA are interchangeable (just be careful about the cage length and chain length). But the 105 uses a different pin(?) that is smaller in diameter. The cylindrical silver part on the cage that fits into the RD (not the screw). 105 has a smaller diameter then DA/Ultegra.

johnpuga1982
Posts: 155
Joined: Mon Aug 14, 2023 10:49 pm
Location: New York City

by johnpuga1982

I purchased a Cannondale SuperSix Evo with 105 Di2 and I switched everything to Dura-Ace Di2 with no problems. I started with the front derailleur, then the rear derailleur, then the crank, and then finished with the leavers and brakes when I installed a one piece handlebar. The only "issue" I ran into was having to setup the bike as a new bike in the E-Tube app when changing over parts. The parts didn't talk to each other until I delete everything and started all over. I had to do this with each part. So I did it three times. Battery and brake lines are the the same.

If you replace your handlebar, you may need to purchase replacement Olives and Barbs for the leavers.

Also, call me crazy, but I think 105 Di2 is better than Ultegra Di2. If you upgrade your chain, rear cassette, brake rotors, and brake pads to the Dura-Ace versions you'll be pretty happy. I did this before I even thought of going full Dura-Ace. Fairly cheap upgrades.

TheBelgian
Posts: 180
Joined: Wed Apr 26, 2023 9:09 am

by TheBelgian

Why did you switch everything to DA? I have 105 Di2 on all my bikes here, and only replaced the shifters with Ultegra because of the remote shifter buttons (and now I am also hooked on the extra buttons to change screens on my Garmin)

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howaboutme
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Location: Northern VA

by howaboutme

Double post. Sorry, please delete
Last edited by howaboutme on Fri Apr 19, 2024 6:06 pm, edited 1 time in total.

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howaboutme
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by howaboutme

TheBelgian wrote:
Fri Apr 19, 2024 5:20 pm
Why did you switch everything to DA? I have 105 Di2 on all my bikes here, and only replaced the shifters with Ultegra because of the remote shifter buttons (and now I am also hooked on the extra buttons to change screens on my Garmin)
You didn't switch to Ultegra brakes? Do the Ultegra shifters play well w/ the 105 brakes?

toxin
Posts: 937
Joined: Tue Apr 18, 2023 5:56 pm

by toxin

they are the same

Eterna7m
Posts: 425
Joined: Thu Jan 07, 2021 11:25 pm

by Eterna7m

johnpuga1982 wrote:
Thu Apr 18, 2024 5:59 pm
I purchased a Cannondale SuperSix Evo with 105 Di2 and I switched everything to Dura-Ace Di2 with no problems. I started with the front derailleur, then the rear derailleur, then the crank, and then finished with the leavers and brakes when I installed a one piece handlebar. The only "issue" I ran into was having to setup the bike as a new bike in the E-Tube app when changing over parts. The parts didn't talk to each other until I delete everything and started all over. I had to do this with each part. So I did it three times. Battery and brake lines are the the same.

If you replace your handlebar, you may need to purchase replacement Olives and Barbs for the leavers.

Also, call me crazy, but I think 105 Di2 is better than Ultegra Di2. If you upgrade your chain, rear cassette, brake rotors, and brake pads to the Dura-Ace versions you'll be pretty happy. I did this before I even thought of going full Dura-Ace. Fairly cheap upgrades.
On my propel my set up is Ultegra shifters and derailleurs, dura ace cassette, chain, chainrings and w/ calipers and rotors.
IME switching from this to my other fully 105 di2 specced bike the only thing I notice and miss are probably the hood top switches.
Besides looks I think the only thing I really "need" are Ultegra STIs and maybe FD.

by Weenie


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TheBelgian
Posts: 180
Joined: Wed Apr 26, 2023 9:09 am

by TheBelgian

howaboutme wrote:
Fri Apr 19, 2024 6:04 pm
TheBelgian wrote:
Fri Apr 19, 2024 5:20 pm
Why did you switch everything to DA? I have 105 Di2 on all my bikes here, and only replaced the shifters with Ultegra because of the remote shifter buttons (and now I am also hooked on the extra buttons to change screens on my Garmin)
You didn't switch to Ultegra brakes? Do the Ultegra shifters play well w/ the 105 brakes?
No I didn't. I don't notice any difference in braking tbh.

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