Full 9270 groupset for a new bike - anything I may have not considered?

daniel_b

Evening all,

as some of you may know, I bought a new 2021 Scott Addict RC30 last year from Hargroves cycles - it comes with Ultegra R8000, but I have yet to ride it, as my CR1 is still going strong, and my brother, who I was going to gift the CR1 to, is not currently in a position to accept it.

I have bought new wheels (Spokesman handbuilt), and integrated bars/stem, XCR rotors, Look titanium pedals for it, which await fitting.

I'd always bought the bike with the idea of making it (within reason) as light as possible, as the CR1 is a whisker over 7kg, I was hoping to get to early 7s or even lower.

The main thing left to change is the groupset - and as luck would have it, my C2W limit has just gone up to £4000, AND my LBS has ordered some of these groupsets in, AND accepts the vouchers - which is a mahoosive win, as it will save me in the region of £1400.

I'm planning to go for a 52/36, with an 11-34 at the rear, and 172.5 cranks.

Having seen the Shane Miller review of this latest power chainset still not reading accurately, I'm going to avoid that, and probably look (partly for lightness) to go for a 4iiii crank as and when they become available.

My other part of the plan, as the RC30 is unridden, will be to sell on the R8000 groupset, as it will basically be new, and would assume I'll be able to get something in the region of £700-800 for it, does that sound about right?

I'll also spec a press fit bottom bracket, as that is what the frame takes, but I just wanted to check I wasn't missing anything obvious?

I have considered SRAM, but I've had a mechanical groupset, and haven't been massively impressed by it, where as I have generally had positive experiences with Shimano.

I also appreciate DA is a massive extravagance, and probably the only reason I am doing so is that the Foil I bought at 33% off happened to come with it, and it is a groupset that I don't honestly think I would have appreciated until I experienced it first hand.

I'm aware the latest Ultegra is probably 99% as good as DA, and probably only a handful of grams heavier.

Additionally, this Addict will be a bike I will potentially never sell, it's the colour I want, a frame shape and design I love, and with the carbon bars/stem, new super light wheels, and this groupset, it will be 'my' superbike.
Chances are I'll probably get the frame clear wrapped as well, as it has some matt parts on it which can mark up easier that is ideal.

Anyway, I digress - is there anything I have missed, or overlooked with regards to the groupset for the Addict RC?

trevor.hall12

My only suggestion would be whatever pressfit BB is in there go with the wheels manufacturing version if they do one ,you'll also get the option of ceramic or normal bearings too .
It's a little bit more money but they are fantastic and there will be 0 creaking issues.

MattFalle

Remember to think about freehub choice as well for if it ever needs replacing.

Munsford0

trevor.hall12 said:

My only suggestion would be whatever pressfit BB is in there go with the wheels manufacturing version if they do one ,you'll also get the option of ceramic or normal bearings too .
It's a little bit more money but they are fantastic and there will be 0 creaking issues.

Well the press-fit Shimano BB that came factory fitted in my CR1-SL frame is still going strong. Never a sound from it and still very smooth. So I'd leave well alone and just swap the chainset.

MattFalle

Munsford0 said:

trevor.hall12 said:

My only suggestion would be whatever pressfit BB is in there go with the wheels manufacturing version if they do one ,you'll also get the option of ceramic or normal bearings too .
It's a little bit more money but they are fantastic and there will be 0 creaking issues.

Well the press-fit Shimano BB that came factory fitted in my CR1-SL frame is still going strong. Never a sound from it and still very smooth. So I'd leave well alone and just swap the chainset.

Same for my S3. Can see no need to change.

trevor.hall12

He said it was pressfit and he needed one my suggestion was go with WMFG for the quality ,it seemed to me there was no BB to remove only to buy one

Munsford0

He says it's an unridden bike with Ultegra groupset. So it has a Shimano pressfit BB already installed. I didn't understand the reference to speccing a pressfit BB either.

You wouldn't knock out the BB to sell with the rest of the groupset; they are not reusable items - bashing them out frequently damages them.

daniel_b

Thanks for all the useful replies all - much appreciated.

I happen to have fitted a ceramic push fit bb to my CR1 SL, from a forum member on here whose bike was knackered in an accident I seem to remember.

I bought it as I was getting some squeaks, and whilst it has reduced the squeaks, some still remain.

Yes the bike will have the original BB fitted, but as the full groupset comes with a BB (And rotors I now gather) I'll be looking at both of those parts as spares for the stock cupboard.

If the stock BB gives me no issues, I won't look to change it anytime soon, if it does though I will likely take the opportunity to move to a ceramic version.

MattFalle said:

Remember to think about freehub choice as well for if it ever needs replacing.

I have to be honest, this did not occur to me when I had them built, I just told him what it was for, what kind of weight I was after, and apart from upgrading to tune hubs, left the rest to him.
I may drop him a line to check - as I understand it, the 12spd cassettes do not require a new freehub, or anymore space than 11spd, so that part should not cause any headaches.

Further investigations on the 4iiii power meter front, seems to suggest I can now send my crank away in the UK, and get the Precision 3 power meter part fitted by them, for £299 - which seems reasonable, as the Dura Ace off the shelf version will be around £500 I think.

My LBS have put an entire groupset away from me, I have paid a deposit, and just need to wait until December now when I can rustle up a new voucher.

trevor.hall12

Munsford0 said:

He says it's an unridden bike with Ultegra groupset. So it has a Shimano pressfit BB already installed. I didn't understand the reference to speccing a pressfit BB either.

You wouldn't knock out the BB to sell with the rest of the groupset; they are not reusable items - bashing them out frequently damages them.

You can pretty much take out most pressfit BBs with the tools that are available now as long as its nit had loctite used .
No violence extractors are great

Bikeauthority.cc

I know this isn't really what you are asking about but just thought I'd add this. I'd highly recommend looking in to other PM options. I appreciate the cost and weight are attractive but crank arm based PMs should be considered the bottom of the heirarchy when it comes to accuracy, consistency and reliability.

Give some consideration to either pedals of a spider based system like quarq or preferably Power2max.

redvision

Bikeauthority.cc said:

I know this isn't really what you are asking about but just thought I'd add this. I'd highly recommend looking in to other PM options. I appreciate the cost and weight are attractive but crank arm based PMs should be considered the bottom of the heirarchy when it comes to accuracy, consistency and reliability.

Give some consideration to either pedals of a spider based system like quarq or preferably Power2max.

What a load of crap! Most crank arm pm's are just as reliable and accurate* as others.

*only time they fall short is if you have a leg imbalance, but then most have a feature in the app to account for this

daniel_b

From what I have read up on, in terms of reviews across the years, I realise that some crank arm pms have reliability issues, water ingress problems etc, or erratic readings.

The 4iiii doesn't appear to fall into that category, although I have noticed some suspect reviews of the 3.0 which is a shame, but am hoping they will remedy these issues with firmware updates - I'll certainly be checking before commiting.

I know my power is generally pretty even, sometimes 48/52 when I am more tired, and I have a set of Assiomas (Similar quality of review to the 4iiii imho) so could easily run them in parallel, and then adjust the 4iiii (That's good to hear there is an adjustment within the app) until it is as close as I can get.

Not sure if I would need a second head unit to take the 2nd set of pm readings though, would need to look into that - I have an older one I can use anyhow if that is the case.

JimD666

Why not just swap the Assiomas between bikes? Kind of thought that was the point of pedal based PM's.

trevor.hall12

I've used 4iii Left sides for years ,other than change the battery now and again and calibrating once a month they have been rock solid and consistent with readings .
Had on ultegra and Dura ace groupsets

daniel_b

JimD666 said:

Why not just swap the Assiomas between bikes? Kind of thought that was the point of pedal based PM's.

Definitely a possibility, but if at all possible, I'd rather just be able to choose a bike on the day and go.

The assiomas are destined for an aero bike which is currently running some unreliable Vector 2 pedals, but I could use them to test the accuracy of the 4iiii, assuming the pedals themselves are accurate of course!

But no, I take your point - that is the benefit of pedal pms, especially when they don't have a finicky setup process, requiring torque meters, or certain angles etc etc.

If I were to go abroad and hire a bike, I would take those pedals with me I'm sure.

MattFalle

As an aside, i know you didn't get on with Mech SRAM but have you tried electronic? different kettle of cats.

lighter, less faffy and prettier....

MattFalle

daniel_b said:

JimD666 said:

Why not just swap the Assiomas between bikes? Kind of thought that was the point of pedal based PM's.

Definitely a possibility, but if at all possible, I'd rather just be able to choose a bike on the day and go.

The assiomas are destined for an aero bike which is currently running some unreliable Vector 2 pedals, but I could use them to test the accuracy of the 4iiii, assuming the pedals themselves are accurate of course!

But no, I take your point - that is the benefit of pedal pms, especially when they don't have a finicky setup process, requiring torque meters, or certain angles etc etc.

If I were to go abroad and hire a bike, I would take those pedals with me I'm sure.

no to 2nd head unit - all you're doing is putting weight on that you're trying to take off.

super_davo

MattFalle said:

As an aside, i know you didn't get on with Mech SRAM but have you tried electronic? different kettle of cats.

lighter, less faffy and prettier....

MattFalle said:

As an aside, i know you didn't get on with Mech SRAM but have you tried electronic? different kettle of cats.

lighter, less faffy and prettier....

11 speed was lighter - definitely not the case with 12 though. Heaviest electronic groupset by miles. Some nice touches like the front shifting presses & true wirelessness, but latest Shimano closes that gap.

MattFalle

I stand corrected re 12 speed weight - grazie.

Shame really. is it because they have dropped a year behind product cycles or another reason?

MattFalle

Sorry - am confused.

Are weights not as per attached? 2507 Shimano 2056 Red?

MattFalle

Sorry - 2439 for Shimano as attached, but still heavier thn SRAM

super_davo

About 100 grams in it in favour of Dura ace according to this article:

https://www.cyclingweekly.com/news/product-news/sram-etap-vs-di2-which-is-better-211408

Difference is much bigger at Force / Ultegra and Rival / 105 level. Red only saves you about 150 grams Vs Ultegra for example.

11 speed Red is going to become highly prized for hill climbers as everything since had got very portly.

MattFalle

First gen 10 speed Red is the way to go tbh - lightest, fully rebuidable, utterly no difference in riding exp between 10 & 11....

MattFalle

super_davo said:

About 100 grams in it in favour of Dura ace according to this article:

https://www.cyclingweekly.com/news/product-news/sram-etap-vs-di2-which-is-better-211408

Difference is much bigger at Force / Ultegra and Rival / 105 level. Red only saves you about 150 grams Vs Ultegra for example.

11 speed Red is going to become highly prized for hill climbers as everything since had got very portly.

overall though, 100g isn't really a deal breaker when you've saddled your bike with heavy junk like discs, electronic this, battery that.....

daniel_b

MattFalle said:

no to 2nd head unit - all you're doing is putting weight on that you're trying to take off.

I think maybe I didn't explain myself clearly, I was just saying that if the Assiomas are decreed as a very accurate power meter, I could carry out some rides with both them and the 4iiii crank, compare and contrast, and then another poster suggested there might be an option in the associated app to effectively cancel out the difference, presumably by altering the power shown from 100% either upwards or downwards.

MattFalle said:

As an aside, i know you didn't get on with Mech SRAM but have you tried electronic? different kettle of cats.

lighter, less faffy and prettier....

You have a good memory, and yes mech SRAM I have not gelled with, and I did seriously consider SRAM Etap, but as I REALLY want to use my C2W voucher, and finding anywhere that has stock AND will accept the voucher is some kind of miracle - especially as it's about 1.5 miles from my house.

So I will stick with the Shimano offering, also partly due to the increased calliper space for the rotor - not a fan of rubbing discs.

That's interesting on the weight point, as posted above by @super_davo , I hadn't even looked into the weights, and had in fact assumed SRAM would be lighter.

Additionally, from a quick skim of that article, I'd need to be changing my freehub.

MattFalle

groovy cannelloni 👍👍👍👍

re weights - i'm as confused as anything as we've all now quoted 3 different weights from 3 sources for the same groupset, and i can't work SRAM's website to find them on there.

dannbodge

JimD666 said:

Why not just swap the Assiomas between bikes? Kind of thought that was the point of pedal based PM's.

That's what I do.
Literally 30 seconds to do, then zero them using my wahoo before riding.

As for the "rubbing" discs, it's literally blown out of proportion.

Mine have a tiny rub (DA 9170) when you move the wheel by hand slowly, but by the time you're moving the road/wind/traffic noise means you never actually hear it and you certainly don't feel it.

I love my DA DI2 groupset. Not sure I'd go for a 34 on the back though, unless you're going up ventoux every day.

I'd look at changing the cassette for an Ultegra, unless Shimano have managed to stop the DA cassettes creaking.

daniel_b

I only opted for the 34, as I do indeed want to take it to the mountains at some point and repeatedly, and thought with the extra cog it's no more gappy that an 11-32.
11-32 was not an option either.

I probably need to check what I have on my CR1 actually, as if that is a 28 (Again paired with 52/36) I'll change this to the 11-30 option.

I also had read about the DA cassettes being a mare, and so on the Foil, sold it and the chain, and went the Ultegra route instead.
It wasn't just the reputation that made me change, I think it also came with an 11-32, and on that bike I wanted an 11-28.

I think I may as well give the cassette a chance on this groupset, and if it gives me issues I can sell on and move to Ultegra once more.

Shorter cranks - discuss.

I used to ride 175s, then on all subsequent bikes, and as it happens any cranksets I have bought, I have gone for 172.5.

I'm not thinking of anything like a 165, but would a 170 be worth thinking about?

I have what I believe to be a long inseam - 34" \ 86.4cm, and am 5ft 10 \ 178cm tall.

daniel_b

Oh and as for the use the Assiomas on the lightweight climbing bike angle permanently, I could do, but I'm striving for lightness (but still modern kit) and the pedals I have bought, plus the weight of the 4iiii will be circa ~108g lighter.

Bikeauthority.cc

For clarity I'm not saying that 4iii ( or any other crank based PM) can't be accurate some of the time but there is a lot of "evidence" of variability over time which negates testing them at first install. Issues such as watt variation based on battery voltage and non rotational forces skewing readings suggest this style of product is not the best.

Personally, and there is a good argument that I'm a bit too anal about accuracy, repeatibility etc, I'd want a product I can confidently fit and mostly forget and the "evidence" suggests crank based PMs are not that product.

As for shorter cranks, I don't think you would see much benefit or notice the difference going 2.5mm shorter. Theory and studies show shorter cranks can have an effect but the effects are generally subtle and only detected because a researcher is specifically looking for them.

What is your goal/expectation by making this change?

yellowv2

FWIW I think you'll find most bike fitters are now suggesting shorter cranks? Am correct in saying you had a bike fit a couple of years ago with the same person I had a fit with?
I can tell you he would definitely recommend the shorter cranks, I am also 5'10 although have an inch shorter inside leg.