Upgrading 8 speed CAAD8 to 11 speed
 

Hello all,

Was searching online for some crank and fd compatibility doubts I had and got directed here from BikeGremlin's very informative page.

I ride a 2014 CAAD8 8 Claris (2400). I want to upgrade it with some old 105 11 speed parts I've gotten my hands on.

I have both shifters, both derailleurs. I will buy a new 11 speed cassette and chain. I do not know if the 105 calipers are part of the package yet (it's still in transit). If they aren't, I plan to keep my current Tektros.

The biggest missing piece of the puzzle is the 11 speed crankset. It was supposed to be part of the package but at the 11th hour I'm told that it's actually a non series Shimano triple and not a 105 series double.

So what are my options? Can I use the current 8 speed FSA Vero crankset with 50/34 rings?

Will the 11 speed shifter, fd and chain work well with it and shift properly without the risk of the chain either jamming or falling off the rings (in between the 2 rings from what I read ...)?

Or would I potentially be forced to stick to the Claris 2400 left 2x shifter and fd already there on my bike, to ensure continuance of front shifting on the existing crank and chainrings? But here I've read that a 8 speed fd cage would be too wide to shift a narrow 11 speed chain properly (or at all), even after adjusting the stop screws.

Would truly appreciate the help of the experts here or those who've gone down a similar path.

P.S. Since this is my first post and thread, a bit about myself.

I'm a 51 year old cyclist, and race in the Master's category, both road races and crits. This is my race bike and I train on it as well, both on road as well as on my indoor trainer (Kinetic). Alloy but I love the geometry and the classic flat top tube look, and up until now have resisted moving to 25c from my 23c tyres. The internal width of the rims on my stock Maddux wheels is anyways just around 14-14.5 mm ... not even 15.

I just realised that I did not add that I would even have to get a compatible 32 hole rear hub that would be able to take the 11 speed cassette, since my current Formula stock hub freehub body cannot accommodate a 11 speed cassette.

I have a spare trainer-only 8 speed wheel for my indoor trainer, shod with a trainer tyre, that I will most probably have to convert to a 11 speed compatible hub with a 11 speed cassette as well, though I've been told that I could likely use it as is and simply not shift the extra 3 clicks consciously, if the indexing would allow. Sounds tempting because anyways on the trainer I am usually only using one gear for the rest intervals, and another for the On power intervals.

9-10-11-12 have the same width so you should be able to swap the claris twin ring for a Sora or find chainrings and swap them. you can also run a sora FD with 105 shifter (I do the opposite) and the front FD system are similar

Thank you Fentuz.

By width do you mean width of the chainring teeth or the gap between the big and little ring?

I've read here and elsewhere that the rollers of all chains of all speeds are the same width, only the thickness of the side plates gets less as the speeds go up, to make the chains narrower for the narrower gaps between the cogs of the cassette at the rear.

So while you "can" use a 11 speed chain on say a 8 speed chainring, while shifting down from the big to little ring, since the gap is designed for a wider chain, sometimes the narrower 11 speed "might" fall in between the two rings.

Also that a 11 speed shifter will only work with a 11 speed front derailleur. As per the Shimano compatibility chart.

To clarify. I have a 8 speed FSA Vero crank and chainrings.

I already have a 11 speed shifter and front derailleur.

So 2 questions:

1) Will a 11 speed chain work on the existing 8 speed crankset and chainrings.

2) Will the 11 speed groupset (5800) front shifter and front derailleur work well for moving this 11 speed chain between the two 8 speed chainrings on the 8 speed crankset.

And added point I did not mention on my earlier introductory posts:

I also have with me an older generation 9 speed Tiagra 4500 (external cables coming out from the sides of the hoods) front shifter, front derailleur and Hollowtech II crankset with 9 speed rings with me in spare, if that might help.

Thanks a ton once again!

no, it will not; the 11s chain is 5.6m wide so it will not fit on 8s cog designed for 7.1mm. Basically, the teeth are to thick to go into the chain gap.

this outer width affect the cassette shifting.

the chainring themselves are affected by the inner width; 2.18mm for 9 to 12 speed and 2.38 for 8 and below.
the chainring shift is controlled by the spacing on the crankset which is the same for 9 to 12 hence you can use whatever chainring and using 9/10/11 front derailleur. Some 11 and 12 may be narrower and rubbing but there is a trim trigger.


FYI, i was talking to the local bike shop about shimano groupset and the owner mentioned that he has been downgrading customer bikes from tiagra 2x10 to sora 2x9 with sunrace wide range cassette because it is cheaper, requires less maintenance and last longer.



https://bike.bikegremlin.com/1220/1-...compatibility/

Thank you so much. That makes it amply clear now.

So to make my 11 speed upgrade work, with what I have, I must replace my 8 speed FSA Vero crankset with 8 speed FSA chainrings with the spare Shimano Tiagra 4500 9 speed Hollowtech II crankset with 9 speed chainrings that I have with me.

Along with that I will also -

1) Replace 8 speed Claris 2400 shifters with the 11 speed 105 5800 shifters
2) Replace the Claris 2400 fd and rd (ss) with the 105 5800 fd and rd
3) Replace the 8 speed chain and cassette with new 11 speed chain and cassette

I absolutely appreciate the economic upside of shifting from a 10 or 11 speed system to a 9 or 8 speed system in terms of cost of replaceables like chain and cassette. Also the 8 speed chains and cassettes and chainrings last a lot longer too. So double benefit. And (as in my setup) with a 50/34 compact and a 11-32 cassette you get essentially the same gear range too. Just bigger jumps. Not an issue at all for recreational riding or touring or bikepacking.

I'm just thinking that with most of the bunch on 11 speed systems in our races, and only a very few of us with 8, 9, or 10 speed, maybe the slightly slicker/faster shifting 105, with some weight gains, and smaller jumps, will make it's advantages felt over longer races.

Thanks a lot once again!

And don’t forget the 11s chain too

and the 11s 11-32 should gapped like a 9s 11-25 +28 +32. Nice close ratio spacing


note that sram pc1110 is a cheap chain that works well and last for some time.
i tried kmc x11 and did 1000miles… noisy

with my 11s 9-46T, I run a eagle 12s chain which I change every 2000miles

Yes, a new 11s chain and cassette.

I plan on getting both from my local Decathlon to keep the costs down (less than half that of 11s Shimano, SRAM being a lot more for the cassette, near same for the chain). The chain is essentially a KMC (my last KMC Z8.1 8s chain with a mix of wet line and later hot wax lasted me 10,000 km so the 11s numbers really scare me) and I think the cassette is either a Sunrace or a MicroShift but comes in only one combination, 11-28.

Both chain and cassette from Decathlon come to approximately 3000 rupees (that's about 30 pounds).

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So….how did it turn out for you?
 

I read the entire thread,….
get to the end….
and now I need to know…
The Rest of the Story.


ebonho - was it worth it?

Executive summary:

• F & R control levers
• F & R derailleurs
• Crankset or narrow 11-speed chainrings (maybe)
• Chain
• Cassette
• Rear wheel

Those who like a challenge can find a 11-speed replacement cassette body, re-space the rear axle, and re-dish the rim.