Compact Chainrings Can Affect The Shifting Performace. Comparison With Standard Crankset.

Visit my cool blog: sickbiker.com/
HUGE bikes and components SALE: tidd.ly/a60a97ae

[@paulmcknight4137]

Very interesting. I'm still on friction shifters and 2 x 6, but years ago read Eddy was "fond" of riding 53-44 "for climbing." So I toughened up and tried it. 44 is a bit tall for climbing with 22 low cog, but found myself in LA, with a replica of the last bike Eddy rode, an SL DeRosa, same weight, same gearing, so thought I'd try it on Mt. Wilson, a 22 miles climb around 5000 ft., gentle until 5 miles from the top and then a pretty serious 6 mph slog. The one thing I noticed practicing in the 44 before LA: shifting was instant. The chain dropped so easily across the 9 tooth difference, it would have been golden in a race, just enough difference to pick up the cadence but not blow up The rear derailleur pulleys didn't have much chain to slack off or pick up. The chain never over shifted or went slack enough to skip off the cogs. The key to climbing in 44-22 was determined, even strained, slow twitch muscle cadence, 65-75 rpm, as always, apportioning effort for the long haul, careful to stay below anaerobic threshold and calling in the fast twitch muscle fibers, and risking default. I discovered the 44 was definitely doable until the last 5 miles. The legs needed at least 60 rpm to keep going and I was challenged, keeping a deliberate, even cadence, and concentrating on breathing more than anything else. I made it in two hours, went back the next weekend and did it again. Triumphant descent through La Canada at 24 mph made it all worth it. If I were going to a 50 t. outer chain ring, I would leave the 39 on. Rode a 50-42 one winter and enjoyed the close shifting, a cog less difference than 53-44, but found the change of cadence as well as the 50 inadequate, so went back to 52, the standard 10 tooth difference. Yes, the low range gearing range overlaps the high range gearing much more than 50-34 or 53-36, even 52-39, but the advantage is I can shift up front half the time quicker and the legs pick up the change of cadence without strain, and don't have to also shift the freewheel cog. Many riders are going almost exclusively with the 50 and seldom bothering with the inner ring. Once fit, their legs never need the small ring, like you suggest. The moral of the story: use what gears your legs and the terrain calls for, jettison the gears you never use but have for "insurance," viz anxiety you might hurt too much. Ride for a year and you'll embrace suffering as part of the game and handle it gracefully. Slow twitch is everything. Finally, those big freewheel pie plates, long cage derailleurs, and long chains, add unnecessary weight the bike would climb better without. A reasonably fit 180 pound rider can go up almost any hill in 42-28 or equivalent gear inches, without a problem. Club riders stay in mid cogs or the big ring, to keep up! I see club riders climbing in their 39-17s all the time as I spin past in the trusty 42-28.

[@jeanmorin3247]

The comments made by MBMB BMBM are very pertinent. I would like to add that without a table of the gear ratios (preferably in in English inches system), you cannot have a good view of the advantages and the disadvantages that a 36 will give you over a 34. The regularity of the spread of ratios is as important as the range of ratios.

[@cmfall1986]

While I agree that shifting can be different- I think a well setup derailleur pretty much nullifies this. I've spent years switching between compact and standard cranksets, and while it does take patience and time to get it shifting well- once you do the difference is pretty much not there. I use sram (yaw) front derailleurs and even with a compact, if I have it setup well, shifting is super crisp and the chain (almost) never drops.

[@belgrano777]

I'm sorry, I find your conclusions plain wrong. Firstly, the front derailleur is set too high. Secondly, the limiting screws should not allow the chain to overshoot the 50t ring. Thirdly, you're using different chainrings brands which makes the rings to be out of "phase" and the chain to sit correctly. It also makes their ramps to be missaligned causing poor shifting. Forthly, you tested the shifting with the rings held (loosely) by 2 bolts?? Fifth, the 50t ring SHOULD NOT be flexible - that's why is made out of 7075 Al instead of steel or other softer alloy. And most important - when upshifting on the big ring you should ease the pressure on the pedal. For the record - I use 50/34 Shimano 5700 rings on an old Sugino crank and the chain never drops - unless I press on the pedal when shifting.

[@cannondany]

+MBMB BMBM Thanks a lot for your suggestions! Just before recording this episode I put the front derailleur a bit higher, so that the chain would not overshift. Before that it could either set the limiting screw so that I couldn't shift to a larger ring, or else I'd experience chain drop - I know it's weird. The solution to this problem was to lower the tension of the cable and the front derailleur once more. Now it's working fine. Cheers!

[@yld244]

I think the reason for the chain getting stuck on top of the teeth when changing to the big ring is due to the "phasing" between the two different brands of chainring. You may be half a tooth out when in relation to the bolt circle. So when switching between rings the chain won't sit in the teeth properly

[@kibbee890]

Best solution is to juts go with a triple. Lots of gear range and nice reasonably sized jumps between the chainrings to make shifting crisper.

[@silaseul3186]

i hope this is not a serious comment :P

[@lynskeyti9940]

Yes sir, been missing 30-42-52 for a while

[@TeslaOsiris]

So far my favorite combo for front shifting is a Sram Force 22 front mech paired against Rotor Aero Chainrings. The spring tension is super high on downshifts to the small ring to where it sounds like a gun shot went off, but the shifting is super fast and reliable thanks to the stock chain catcher. The only misshifting I've had was when my chain was too dirty and wouldn't catch up when upshifting to the big ring. It was an isolated incident and hasn't happened since.

[@cannondany]

+TeslaOsiris Yes, I do love front mechs from Sram.

[@123456bmx]

TeslaOsiris this is hilarious,I remember when I first built up my bike and went on a group ride.My frame didn't have a barrel adjuster on the downtube so I just left the cable tension super high.A few people commented that on my ride that my front downshift was so loud.

[@vn3801]

1.00 Compact - small ring is 34T not 36T - prob just a verbal typo

[@TigrrrTamer]

YOU ARE NOT MEASURING IT PROPERLY. Learn to use your Vernier correctly. Use the back end of the Vernier, nestling the back in the valley between the teeth, and the slider bar (inside) to the valley on the smaller chainring. Find 2 valleys that lign up so you do not get a false measurement from a diagonal. I measured a Compact 50/36 and a Standard 53/39, and they are both about 29mm distance. If there is in fact a difference in shifting performance, it is either A) your derailleur is the wrong height (it looks high in the video) or B) the reduced radius of the Compact's large chainring is smaller than what the curvature on the derailleur is designed for, or C) your ramps and cutouts are different and not as good on your Compact as they are on your Standard

[@theylivewesee1674]

It's true I have compact FSA crainrings with Microshift shifters and really doesn't shift that well in larger gear, I always have to hold the shifter and hope it will change gear

[@cannondany]

+Esseker Fit And what do you think about the shifters themselves?

[@theylivewesee1674]

cannondany very crisp and precise also loud for a budget groupset but the upshift from 1st to 2nd cog wheel on crankset is somewhat delayed

[@jubilaru8789]

never thought at that... i have an old carbon race frame that was designed for braze on derailleur and 53 chain ring. using it with a compact made it impossible for me to respect the derailleur - chainring distance recommended by shimano. but that was a good thing , because having it at ~5mm upper, gave me a very fast , precise and predictable shifting (even with friction dura-ace shifters)

[@brucewayne3141]

Downtube shofters are gonna shift no matter how big the gap is. Sti is a different story.

[@recumbentogiro26]

Too much slack in the chain. I think you haven't shortened your chain to match your new gearing. Too much slack causes sloppy shifting

[@andrewclarke9817]

Your chain is way to slack. I noticed that right away! Get rid of 2 or 4 links and you will see shifting improve greatly.

[@41778055]

Do you feel much of a difference on steep hills with the 34-36 change?

[@tomjom4865]

My bike has a 45 single chainring going to a 14-28 rear casset should i change the 45 to a smaller one

[@user-cx2bk6pm2f]

Is it fair to build a mix-matched Frankenstein bike then complain it doesn't work smoothly? If these were full Shimano/SRAM/Campagnolo there would be absolutely no shifting issues.

[@ivanboesky1520]

Your front derailleur is far too high on that FSAa 50/34 compact crankset. It will never shift well with your front derailleur in that position. It has absolutely nothing to do with the crank makes, models or the standard versus compact sizes themselves. To do a proper comparison you at least need to have the front derailleur set up properly. Any decent derailleur should be able to deal easily with a 16 tooth gap between the big and small rings on a compact 50/34 crank. If you took a standard sized Campy 53/39 and set it up properly, and then threw the exact same Campy series crank in a compact 50/34 size on there with the front derailleur sitting that high on the compact the Campy compact of course would shift like crap because the FD set up is a mess.

[@dtshifter]

I have been riding 53/39 for years with a 12-25 cassette. I am looking at a new bike that comes with a 50/34 and an 11-28 cassette. When using the 50t chainring and 11 tooth cassette I will actually have more gear inches than I did with the 53&12. My question is can I put a 39t inner chainring with my 50t and have the teeth and chain line up for a good shift? There is just no mountain high enough around here to ever use that tiny 34t chainring.

[@waynosfotos]

John O'Neill I am looking at doing this too, shimano and campy have multi purpose cranks fitting standard and compact. My bike shop owner runs a 53/42, which gives a very similar tooth step, although he uses the old campy standard spider. I will be asking him next week about this. The main reason I am looking at this is a compact when doing low to mid 30s km per hour you are right over in the small cogs then you jump to the big cog and I feel the jump is just to big between the small and large ring. So I am going to try a 50/39, Why oh why manufacturers don’t make more ring sizes, especially with the one size spider now, sizes like 48/34, 48/36, 46/36 and 46/34. These would be much much better for the casual weekend warriors. Less jump and 50 - 11 is just a massive gear to push for less fit people.

[@Digi20]

Well just because you have a 52-11 does not mean you have to max it out all the time. you get a much better chainline when you are in the third or fourth cog.on the other hand with smaller chainrings we would have finer jumps between gears. i wouldnt mind a 46-38 (or so) myself. i live in the flats, even with a 11-25 cassette, i never need the extreme ranges.

[@avoycendeether8869]

I ran 50/39 chainrings for over 10k miles before they wore out. Using shimano 57xx front derailleur. Moved to 46/38 but had to make compromises since it violates MINIMUM tooth difference spec. Did a vid on that. Anyhow, at 110rpm a 46 chainring on an 11 cog running 700c wheels will send me down the road at >35 miles per hour. I don't find myself on too many rides where I need more speed than that so I have to ask: why carry the extra weight of a bigger chainring? It can be >50 grams. People spend big bucks to drop 50 grams.

[@cannondany]

+Avoyce N Deether Thanks for sharing!

[@michaelcloherty5352]

Why not have a 39 50 with a 42 or more on your cassette with a road link wolf tooth no more chain ring confusion

[@Demon09-_-]

Don't forget the same slightly worse shifting happens on mid compact as it's still 52-36 which =16 just like a compact. But it should not be as notiable as his test

[@michaelhammond4150]

That is WHY i like Di2

[@ayomideabejide1159]

Do you know of any brands that sell bicycles with a standard crankset (53 teeth/39 teeth)?

[@sarabouh3140]

How I can combine triple crankset 52 teeths with 34 and 22 teeths for an mtb how I can know that is compatible.

[@ruelandrewernacio5357]

i use 52/39 is there any big change in comfort and cadnce if i change it on a 36 chainring. coz the diff. is only 3 teeth. what im concern is budget.

[@ruelandrewernacio5357]

I had a 39front - 28rear drive and i suffer and sometimes dismount on my bike on a climb over 800ft elevation and almost 2km dist. maybe i should train hard or maybe i should loose a bit of my weight. im 80kilos.

[@cannondany]

+juan tamad If you like to climb, the 36 or even 34T front chainring will help. 3 teeth make a huge difference.

[@ruelandrewernacio5357]

i see, maybe 36 is ok to me.

[@stuartperry8141]

I feel it is much easier use and to climb with a 39 front chain ring opposed to 34 t front chain ring.

[@ruelandrewernacio5357]

not realy easy but fast i think.

[@fyahwerks]

very good peice of info there danny. a greater chain travel between 50t and 34t. but i like the 50/36 chainset. but 52/36 with a 10 sp tiagra cassette. when the 2016 set is coming out

[@cannondany]

+Brian Carless Yeah, 50/36T works better for me too.

[@fyahwerks]

+cannondany i like the 50/36 combo. but the 52/36 is just the right comba. when i started in cycling the cranks were 52/40 or 52/52. gear clusters were 5sp 6sp. but when shimano sis came around with their seven speed that raise the bar. big fan of your show. Good work.

[@TeslaOsiris]

Have you thought about using a 46/36 cyclocross chainset? Since top end speed isn't a concern?

[@cannondany]

+TeslaOsiris I would probably be a bit to slow on some descents, but it isn't a bad idea. Cheers!

[@stuartperry8141]

What is the difference between 53 teeth and 39 teeth of the standard compared to 50 teeth and 36 teeth of the compact?

[@cannondany]

kzbin.info/www/bejne/nKaclHiqaJmYnNE&lc=z13qepk4ztqrszzyl04cebrxzv33h3d4ig0

[@user-cx2bk6pm2f]

Is he calling the 50/34 a 50/36 deliberately??

[@jajacollins]

Can i combine 46 22 chainring in mtb?

[@leehyson9831]

You are missing a chainring bolt and your f.mech is too high.

[@shadigif8916]

sick sick sick bike!!!

[@shadigif8916]

sick

[@nasharuddinmohamad8632]

How about 50/39?

[@lyanbv]

so what is the conclusion?

[@skymaracle]

lower your front derailleur, spec is 1-3mm you look much higher than that

[@cannondany]

+sky Maracle Thanks, I just put it a bit higher, as it worked to stiff while upshifting. I must say this one is tricky...

[@gtranquilla]

A longer crank arm gives the rider more climbing power regardless of all the other gearing options.

[@TigrrrTamer]

You are comparing the shifting performance of Campagnolo with FSA... of course the Campagnolo will shift better! LOL

[@ivanboesky1520]

TigrrrTamer Campy shifting is garbage. clunk, clunk, clunk, and a silly stupid thumb button. LOL

[@psotnikkk]

jest polski jest angielski kiedy niemiecki ?

[@cannondany]

+psotnikkk Ich weiss nicht ;)