1GG !

GSAstuto

Maximum Pace
Oct 11, 2009
945
242
103
tokyo
www.roadfixie.com
#1
It's that time of the year again (1st week after Thanksgiving) when real racers put away their roadbikes and swap in their Mulettos. I kicked off this season's FG ride with Patrick around Odarumi / WADA. Since it seems more of you have single speed / fixed bikes to train and ride - NOW is THE TIME!

As somewhat usual I'll be doing the Palace loop thing. This is a good place to start. On the weekends I usually like to get a nice LSD with a climb or 2 thrown in. My favorite FG routes are:

1) Tokyo -> Arakawa -> Tokyo (flat and good for just getting cadence work or hiki)

2) Takao San-Guchi -> Wada West side (Rinko option).

3) Yabitsu Canyon - Up and back on the river side.

4) Anything in the Greenline - A bit longer ride out and back.

Pretty much game for anything here - and of course, Santa suits wear is mandatory during the 12 days of Christmas, with auxiliary accordion on 23rd - 25th.
 

mxs

Speeding Up
May 14, 2010
65
13
28
Tokyo, Japan
#2
GSA, what is your typical gearing choice and do you take advantage of having a double sided rear hub? I am in the process of rebuilding my single speed Pista into a fixed training bike and and wondering what size rear cog to go with. I used to ride 48-17 free gear and was thinking of doing either a 17 or 18 fixed cog.
 
Jun 9, 2011
241
1
36
tokyo
#3
i am so down for riding with a group of mostly fixed/single speed folks. it won't be as satisfying getting up or down a big hill faster than folks on geared bikes, but i figure i'll probably be able to make up for that with volume.

as to gearing, i ride fixed with at 41 in front and flip flop 13/17 in the back. I'd like to use a 19t hill cog but 17t is the biggest i can go and still use a 13 with my current rear dropout.
 

GSAstuto

Maximum Pace
Oct 11, 2009
945
242
103
tokyo
www.roadfixie.com
#8
Actually for winter fun training I prefer not to flip flop and just run a lighter gear all the time. So - like a 44 /19. For longer rides that I want to save some transit time then I'll resort to a flip flop and use like a 44 / 13 or 15 and 44 / 19 or 21. For climbing - my best performance is around 60-70rpm and for transits it's 90 - 120rpm , so I just base my choices around that. It helps to have super long dropouts as well (ala Kalavinka).
 

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#9
Your gearing info is interesting to me running the numbers in > Sheldon Brown's Gain Ratio Calculator < I get some interesting numbers

I'm running the old MTB single speed, 26" wheels, 175mm cranks and a 38-14 gear set, I get 4.8 as a gain ratio.

Running your numbers, assuming 700C x 23 wheels, 170mm cranks you get these gain ratios....

44-13= 6.6
44-19= 4.5
44-21= 4.1
41-17= 4.7
41-13= 6.2

The 4.8 gain ratio I'm getting seems to be in the ball park.

Last night on my little buz around the hood on fairly flat ground, spinning as fast as I could I hit at top speed of 34.4 Km/h, not like I can do that all day long, or even for more than a short burst, but it was interesting.

So these Single Speed/Fixie ridew would be WATT as well as WTTT (Walk To The Top) rides :D

Cheers!
 

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#12
if you want to plan you gearing on paper, the Rabbit calculator is where it's at. speed at cadence is one of the more useful calculations, especially for fixed gear.
That is much easier to use, very cool link, thanks!

I see that on my bike a 48/19 and a 38/15 are the same, what is the advantage of running the larger chainring and sprockets? Less wear on the chain as it does not have to turn such a tight corner?

Just curious is all, as I have both sets, but I'd have to add a link or two back to my chain some how.... :warau:
 

joewein

Maximum Pace
Oct 25, 2011
2,445
917
133
Setagaya, Tokyo
joewein.net
#13
what is the advantage of running the larger chainring and sprockets? Less wear on the chain as it does not have to turn such a tight corner?
It's not just the angle around the tight corner. The leverage of larger chainrings and sprockets means less force pulling on the chain and its rivets, which should be good to keep down wear that causes so called "chain stretch".
 

GSAstuto

Maximum Pace
Oct 11, 2009
945
242
103
tokyo
www.roadfixie.com
#14
This is a religious question. One side says BIG BIG and the other says SMALL SMALL. If you think about it from a torque over time perspective - a larger ring on the front pulls more chain per rotation. Mashers or low RPM power horses will probably feel more comfortable with larger front rings, and those hamster types will probably feel more comfortable with smaller.

Given the average rider tends to develop most of their power around 65 - 75 rpm - you should try to gear accordingly using the largest rings possible (my preference).

Also- try to choose combinations that will vary the skid patches - and also correspondingly chain wear.

And, yes, running the chain across a larger radius reduces the wear and friction, plus it also reduces the stress per link.

Downhill and MTB'ers , plus BMX'ers will choose smaller sprockets so they can get more ground clearance, strength and to some extent better sprinting response. But as I am not a BMX / MTB'er , I'd have to defer to those in the crowd to further explain this.

That is much easier to use, very cool link, thanks!

I see that on my bike a 48/19 and a 38/15 are the same, what is the advantage of running the larger chainring and sprockets? Less wear on the chain as it does not have to turn such a tight corner?

Just curious is all, as I have both sets, but I'd have to add a link or two back to my chain some how.... :warau:
 
Jun 9, 2011
241
1
36
tokyo
#15
smaller chain rings look cooler. I have something like a 26/8 on my 26" park bike. for ss or fixed more skid patched also translates in to more even drive train wear. the 41t chainring on my fixed gear is a prime number meaning I don't need to worry about skid patches. I get Xt patches for even rear cogs and 2Xt patches for odd because I can lock my rear wheel ambidextrously.
 

bird

Speeding Up
Nov 30, 2010
322
18
38
Kawasaki
#16
As I've just recently started riding fixed gear, I guess all the information and discussion here will give me a lot to think about/try around.
The Rabbit calculator is really handy, thanks Patrick!

Currently my setup is optimized for urban commuting with 49/18t. I haven't been to a REAL hill with this so far, but now I can guesstimate that my cadence would go down to 30 rpm on a 10+% climb... as long as I don't injure my knees, that is.

As for choosing between BIG/BIG and SMALL/SMALL, I guess SMALL/SMALL might be better if you use flip-flop hub and want to maximize the gear ratio difference. For example, if your dropout allows up to 4t differences, 12t/16t combination gives greater difference in ratio than 18t/22t.
 

GSAstuto

Maximum Pace
Oct 11, 2009
945
242
103
tokyo
www.roadfixie.com
#17
That's why i like the 42 or 44 front ring. Good compromise between torque efficiency and flip flop spread. I find that with smaller ring, when I get into steeper hills I.e. lower cadence I cannot climb as smooth of efficient I need to keep the cadence higher to get the power out of the ring. As example, though, when I did hillclimb in competition I used smallest ring possible on my crank which was 38. I would prefer even smaller, it did not have BMX style crank to use it. The difference being in a sprint event where you know the expected terrain, you can tune more to the best gear choice. And high cadence is necessary to achieve highest VAM. At least you need to be spinning more tha 50 or your power output wil just suffer (and you, too)

I know this sounds like I a contradicting myself, but it's the difference between riding in a competitive event, agnostic training and general road riding on varying terrain.
 

Quicksilver

Maximum Pace
Jan 9, 2011
117
32
48
Tokyo
#18
Really interesting to see what gears you are riding. Quite heavy gears for around town! I have rather odd setup at the moment (probably as a result of having weak legs and will power but wanting to ride in the hills anyway:warau:). I put on the White Industries double-double which has a crank with 38 and 35 and freewheel with 16 and 19. You can only run big-little combinations but as the total number of teeth is the same you can change from one to the other with the wheel in the same place on the dropouts so no need to adjust the brakes. However around town or for going out to the hills I use a 14 tooth fixed with the freewheel as a flip-flop. (This by the way more or less uses up the length of my dropouts but will take me anywhere except up Azami Line). I generally prefer the 35 as it is quicker to get up to a comfortable cadence and OK for little hills. I really like the idea of the low all rounder 44x19 which looks close to the 38x16 but cant imagine using this on longer 10% climbs. Do I just need to train harder? ;)
 

FarEast

Maximum Pace
May 25, 2009
5,528
538
193
Yokohama
#19
Actually if this is off season training then you should be focusing on pedalling economy and looking for incredibly high cadences, around 130-140rpm averages.
 

GSAstuto

Maximum Pace
Oct 11, 2009
945
242
103
tokyo
www.roadfixie.com
#20
Exactly. For winter training for road racers this is exactly what the fixed gear training cycles were for. 6 weeks. No more than 50% effort building to 100% effort for sprint training at high , controlled cadence. Generally as the race season progress (or back in the big gear days) , the riders would push increasingly heavier gear and slow their cadence down as physical fatigue and general conditioning would led itself towards that. The winter fixedgear 'Muletto sessions' gave you a chance to 'reboot' your pedaling style and cadence memory. It also works slightly different set of muscles (my legs are killing me now)and thus activates muscle growth to round out your conditioning.

I will drop down into my 42 /19 gearing for most rides in the next few weeks. I get alot of razzing cause my speed is low - but the point is , I'm not going for speed, just working on cadence memory and pedaling. Of course hitting the weekend fun ride is ALSO in my schedule because I am not racing and really not training all that seriously. Otherwise - every minute on the road would be applied to a fairly tight schedule of specific exercises.

I'm just hoping a few of you newer FG owners, and older ones, too, will enjoy the camaraderie and pacing of a few FG rides. It can get pretty monotonous when you're dragging a tire down the Arakawa alone in the rain.

Actually if this is off season training then you should be focusing on pedalling economy and looking for incredibly high cadences, around 130-140rpm averages.