ThermionicScott 

I wonder if it would be possible, if you got your hands on the special bolts and trimmed down the crank spiders a little:

Marcus_Ti

Probably...but Praxis did some very precision sneakiness to pull off 32T on 110T BCD.

And I'm curious how long term those rings perform, given any chainring wear at all with those bolt heads so close to the chain

ArDachaidh

Thanks for the suggestions and links - interesting. I still think I'll try the IRD cassette first and then think about a new crank if that's still not low enough, probably the Sugino as it will fit the existing BB. Also the 50T outer is way too high for me (70 years) except downhill. I'll really only be riding on tarmac with this bike, though well compacted gravel might be possible occasionally.

Here's how I see the low gear options: 50/34 11-32 Ultegra = 28.63; 50/34 12-36 IRD = 25.39; 46/30 11-32 = 25.39; 46/30 12-36 = 22.42. The capacity of the Ultegra is 37T and the rear derailleur recommended limit is 32T, but 36 is said to work. I've read some have used a 40T cog with a Roadlink, as mentioned in the review above.

Cyclist0108

@ArDachaidh I'm using a 46/30T now with an 11-36T SRAM cassette on one of my wheelsets (the other has 11-32T Shimano) and the Ultegra derailleurs cope fine.

Cyclist0108

I probably should have got that rather than WI.

ArDachaidh

Thanks for that, WG. Looks like my 12-36 should be ok when it arrives. Can't understand why Shimano don't offer some other options like 46/30.

BluesDawg

Even pro racers feel the limitations of the current offerings from the major companies (who sponsor them).
Jay Petervary

DougG

On an older bike, I had a gearing setup that really was beyond the derailleur capacity when I switched the inner ring on my triple crankset from a 30 to a 24-tooth. But really the only time this was an issue for the derailleur would have been with max slack when I was in the small ring and the smaller rings on the cassette, which there is no need to ever use (should go to a bigger ring) and besides is severe cross-chaining. The only time I dropped down (carefully!) to the small ring was on a steep climb where I was already on one of the larger sprockets, and I'd shift the front back up as soon as pedaling became easier at the top.

Shifting in front did have to be done carefully due to the big 24-to-39 tooth gap, but I think I only dropped the chain once or twice.

Velo Fellow

I'm using a 44/28 White Industries crank and rings with a Shimano 12-27 cassette. This gives me a 28-98 gear inch range. I spin out around 28 mph which, for 70 y.o. me, is just fine. (After a pelvis breaking wheel-touch crash a few years ago I began to sense my own fragility and mortality and began descending more cautiously.)

cccorlew

I just finished updating my 2010 Roubaix Expert to eTap and a new Praxix 48-32. I blog about it here.
Curtis Corlew in Bicycle Land: SRAM eTap, Praxis 48-32 cranks and the perfect bike ?a review

I also FINALLY got the 46-30 FSA Mega Exo crankset for my commuter. It's installed and I promise to post photos or at least a blog entry soon. First impressions: Great gear ratio for my commuter bike.

DougG

I certainly like my 46/30 setup even though I was unable this season to ride it in the conditions that I bought it for (have just been in the flatlands this summer). I'll be interested in hearing about your experience.

nicous

Hello,
I have just bought the FSA Modular 46/30 to replace a Tiagra 4600 50/34, with a BB to replace a BB86.
All is installed now but I cannot properly setup the front derailleur which stay too high.

Front derailleur is a braze-on Tiagra 4600 which is described to handle Top Gear Teeth: 50-56T
Will a Dura Ace 9100 more suitable as described to handle Top Gear Teeth: 46-55T, or is this purely marketing ?
For those who have already got it installed, can you please tell me what is your front derailleur ?

Bike is a Scott Contessa Solace 35 from 2015. I have already changed the Rear Derailleur and Right Shifter to Tiagra 4700 to handle a 34T cassette.

Many thanks

DougG

My front derailleur is standard 105 5800, which is the same one offered for "standard" chainrings from 50-55 teeth. Shimano doesn't say anything about smaller rings since they don't (yet) make them for the 105 lineup, but it's not an issue. There are mainly two things to watch for:

1. The difference in teeth should be 16 plus or minus a couple, which is the case for 50/34 or 46/30, etc.
2. The derailleur should be mounted at the specified clearance from the rail to the top of the teeth of the larger ring, which I believe is about 1mm.

I can't tell from your photo, but it's possible that since your bike was designed for a 50/34 minimum crankset, your braze-on mount is not positioned to set the derailleur low enough. In the photo it looks like you have it at the bottom of the slot, so if the clearance is still too large then there might be a problem (my bike was designed for a 48/32 or 46/30 crank, so I didn't have that problem).


That said, are you actually having problems shifting the front? Front derailleurs aren't as "precise" as rear derailleurs and it seems to me that just "close" might be close enough.

Bnystrom

Since I reported that I had ordered a couple of FSA SL-K Adventure cranks, they arrived and were sent back because they were 48/32, not 46/30. Universal made a mistake on their site which led to the problem, but to their credit, they immediately took the cranks back and refunded my money. They corrected their site as well. No harm, no foul.

I now have two cranks on the way from Performance, which with a "15% off everything" sale were under $300 each. I should have them installed by this weekend and will report back after we give them a workout.

The Di2 will take some tweaking to get the optimum shift points. I'll start with the 50/34 chainring setting that has the same 16 tooth difference as the 46/30, the work from there.

Bob Ross

Are these also FSA SL-K?

Bnystrom

Yes. They started getting them a couple of weeks ago, as best I can tell. Their site alternately said "only 1 left" and "backordered" whenever I checked over the course of 3 days, but at the sale price, I figured I'd just put them on backorder last Thursday night and wait. Lo and behold, they shipped them on Monday. I've been tracking them on the UPS site and they'll be here on Thursday.

My only regret is that I missed out on 20% off sale by one day. Oh well...

dim

you are 70 years old, you have a weak pevis and your average speed is 28 mph (45.0616 km/hr)? .... are you on drugs?.... I want some

Bnystrom

What he means is that he spins out his top gear at 28mph, but he didn't specify on what kind of terrain. The logical assumption would be that this is on downhills, at which point he coasts if the bike goes any faster, or brakes to keep his speed down.

A broken pelvis doesn't mean that it's weak, it just means that he was in a bad crash. I've known several people who broke their pelvis in bike accidents at a relatively young age. Personally, I broke a hip in a low-speed crash at age 41. It's not about having weak bones, it's all a matter of what you hit and how you hit it. Sometimes low-speed impacts where you hit the ground with a thud are more damaging than higher speed impacts where you tumble or slide.

Schadenfreuder

Been looking for a 46/30 solution for my Cannondale Slate 105.
FSA's modular SL-K looks to fit the bill especially as the slate has a BB30a asymmetrical bottom bracket.

However, on looking more closely it appears FSA use the same spline profile as Cannondale (BB30 open standard?) for their modular BB386EVO cranks....
Got me thinking: would it be possible to fit the SL-K 46 and 30 chain rings to a Cannondale Slate Si crank????
I can get these from Germany or Italy for about 150Euro (+ chain ring bolts price TBA)

I was tempted to wait for Cannondale to release a 46/30 Spidering: rumour had it there might be one before 2018.
But after an email conversation with a guy from Cannondale they say they currently have no intention of releasing a sub-compact Spidering... at all!

Thoughts fellas?

DougG

I don't have the specs in front of me, but I seriously doubt that the bolt circle diameter and bolt spacing pattern would match. My FSA 46/30 crank is very unconventional in design.

Schadenfreuder

FSA SL-K use a direct mount spidering type arrangement of their own with a smaller inner chaining bolted directly to the larger outer.

Sorry I should've put these photos on my original post...

Thought with FSA and Cannondale using the same (Cannondale's open source BB30) splines it might be a short cut to getting 46/30 (or 48/32 if you like) for those running Cannondale Si cranks.
It looks like Cannondale have no intention of an in house sub-compact crankset in the near term apparently

xraydog

I recently put a FSA 46-30 crankset with carbon fiber crank arms on my 2017 Sequoia Elite. Lovin' every minute with this new setup. I live in the mountains of Northcentral PA so there are very few flat roads. The extra low gearing is nice to have when your climbing hills all day. No more grinding. I have spun out the lowest gearing going down a steep hill, but then again that was at 40+mph. I don't do that often, I spend much more time climbing than I do at 40+mph.

Schadenfreuder

Hi - nice one!

Promise I won't hi-jack the thread

If your's is the FSA SL-K (same as my previous post) you might be able to help me - could you please measure the crank end of the crank legs, so I'll know if my Cannondale Si's will fit the chain ring... as on the attached pics

This is what I love about the cycling community!!!

Cheers and thanks

Bnystrom

Both cranks arrived yesterday and I've installed them on both of our 'cross/gravel bikes. My girlfriend's went smoothly, but I had and odd issue with mine.

When I tightened the right arm (the spindle is mounted to the left arm at the factory), it didn't want to get very tight. I would crank it down, then a few seconds later, I could tighten it more. Very odd! This pattern repeated for several rounds until it finally seemed to be fully tightened. I also noticed that the chainrings were wobbling slightly at first, then less as I tightened the crank. This turned out the be a dead giveaway as to what the problem was.

I pulled right arm off again and used a Q-tip to spread the grease around in the splined cavity. I noticed a couple of large flakes (~4-5mm) of something that looked like clear plastic in the grease. Apparently, there was something in the crank arm cavity before I started assembling it. Whatever it was compressed slowly as I tightened the crank, producing the odd symptoms that I saw. After removing the junk and reassembling the crank, everything tightened normally and the chainrings are running true.

On my girlfriend's bike, I installed the right arm, pulled it off, checked inside the cavity and spread the grease around more, then reassembled it without any issues.

So, before you install these suckers, spread the grease around in the right arm cavity while checking for foreign material, spread the excess on the spindle and crank it down. It seems to seat best if you repeat the process.

I'll be heading out for the local trails shortly and will report back afterward.

Cyclist0108

Sounds like you just ruined the interface with the mechanical doping motor cam.