Escapades - the bike shop, Goa, Location and other details

Cycling is not only a means to move around but, also a fantastic way to experience a ‘high’, a great way to explore and stay fit, whether on ROAD or on the TRAIL. Do you remember your childhood bicycle escapades?, certainly you do!......, why not relive it !

‘Escapades’ is a small venture, operating from home. The shop intends not only to sell the bikes, but, provide quality service, popularize cycling, conduct workshops on maintenance of the bike, organize biking events……

• Since the shop is part time venture, please call 09823905756 or email -escapbikes@yahoo.in/ajd2k7@yahoo.co.in to ensure the shop is kept open for you : - ))

The bikes presently available at the shop are KHS ALITE 150, ALITE 500 and ALITE 1000. All these are mountain bikes. KHS FLITE 300 and FLITE 500 road bikes are available against order.

KHS bikes website

KHS 150 specifications – price Rs. 16,000
KHS 300 specifications - price Rs. 19,000

KHS 500 specifications – price Rs. 23,000

KHS 1000 specifications – price Rs. 30,000

Escapades Address - H.No.23, Prabhunagar, Rajiv Kala Mandir Road, Behind Sapana Park, Ponda, Goa.

Escapades location map

Photos - KHS ALITE 150 and 500

Some Number Crunching on Gears

27-speed is not equal to 27 gears. How’s that?

I'm using 27-speed only as an example but the principles apply to almost all bikes with front and rear gear sets. If you have read about gear ratios, diligently derived every ratio that your bike offers and imagined using every combo in sequence, the ratios may have come out looking like this (I’m doing it for the first time myself, so please don’t mind the showing-off):

The graph above is simply a visual that represents this table of gear combinations.

Notice how some of the results are very close to each other? Any values lining up almost horizontally on the graph represent similar ratios. So here’s the disturbing fact - not every gear combination actually gives you a unique ratio across the range of 27 combinations.

That, combined with the ‘forbidden’ combinations that result in cross-chaining, effectively kills off many of the theoretical 27 gears possible. Take a look at this table – it suggests a sequence of gear combinations which:

1. Follows a linear sequence of shifts, switching between front and rear shifts.
2. Avoids any serious cross-chaining.
3. Achieves a pretty smooth progression of ratios from the bottom of the range to the top.

And here’s the (ahem, beautiful) chart.

Somehow makes a lot more sense, doesn’t it? And therein lives the mantra of a Good Shift Pattern. If you count the number of shifts it takes to cover this range, it comes to 10 (11 combinations minus 1) according to my chart, but could be 11, max 12, if you insist on a couple of overlaps ;) But there it is - more with less! No overlaps, no cross-chaining and a progressive rise of ratios across the range. You're getting the whole meal of 27 gears with just 10 shifts. The table and chart above translates to a shift pattern shown in the figure below:

If you read the shifts along the rear cogs - it reads 2, 4, 2 shifts. This pattern could very well change to 3, 2, 3 as long as you don't hear any cross-chain rattle. The thing to remember is to time your front derailleur shifts in accordance with the rear sequence.

Side note: Why is the 2^nd chainring combined with 5 cogs and the others only with 3 each? That's because from the 2^nd chainwheel’s chain-line the chain can be pushed either 2 cogs in or 2 cogs out at the rear (middle fig. below) . But from the 1^st chainring you should only go 2 cogs out (left fig.). From the 3^rd chainring you should only go 2 cogs in (right fig.). You could shift 3 cogs but that might risk cross-chaining or ratio overlaps, neither of which will get you top marks in bicycle heaven. Click on the figure below for a better view.

Hope that helped. I'm no engineer, but I love this stuff. If you want to talk more about this crazy topic do leave comments, suggestions, corrections etc. Hope that this write-up has shifted your view on gear shifting, for the better.

Gear up! And clench some teeth ...cuz this goes deep

• If you’re riding anything over a 6-speed bicycle this write-up might be for you.
• If you have heard about cross-chaining but aren’t sure what it means then it is essential you read this.
• If you happily believe that your bike gives you 27 gears because the label tells you so, or because you did the math up to multiplying, say, 3 (chain rings) times 9 (rear cogs) equals 27, then this will be a humbling but enlightening few words of gyaan (Coming soon in the next post)
  

Not to be disappointed with that last one – 3 times 9 will always equal 27, but the idea of this post is to tell you that more can, and should, be had with less. More (range of gear ratios) can be had with less (number of shifts) AND again, that more (performance life of components) can be had with less (wear, damage and breakage). On that uplifting note, let’s get into this Zen like business of getting more from less!

Let me start by elaborating on the 3 points right there on top.

What’s with over 6-speed that makes this article useful?

Most bikes up to 6-speed will have all cogs at the rear freewheel / cassette and one chain ring up front. The entire gear range can be used by shifting the sole rear derailleur. Cross-chaining has an almost negligible presence in this scenario.

Anything over a 6-speed bike, and we have a new set of variables – the front crankset of 2 to 3 chain-rings plus the front derailleur. This is where cross-chaining can rear its rattling head and put your bike’s health in the red.

What is cross-chaining and why you shouldn’t cross paths with it.

Two terms needs to be mentioned before cross chaining:

Chain-line: the angle of a bicycle chain relative to the centre-line of the bike's frame.http://en.wikipedia.org/wiki/Chainline

Centre-line (of the frame): an imaginary vertical plane that runs down the centre of the bicycle frame. It is essentially the plane of symmetry of the frame.

The happiest situation is with a chain that’s perfectly parallel to the centre-line of the frame, equidistant at the bottom bracket and rear hub. This will be found on all well-built single-speed bikes. That’s probably one of the reasons why purists love their single-speeds so much ;)

On a geared bike, selecting gears involves moving the chain closer to or further away from the centre-line at either end. This causes the chain to not remain parallel to the centre-line to varying degrees. Push this to the extremes and you have cross-chaining. For example, selecting 3^rd gear (outermost) on the crankset and 1^st (innermost) at the freewheel OR 1^st (innermost) on the crankset and 9^th (outermost) on the freewheel.

In general, cross-chaining is a consequence of selecting gear combinations that bend the chain considerably out of ‘chain line’. Chains for geared bicycles are engineered to flex a certain amount for smooth shifting and will tolerate operation out of chain-line without much complaint. So how will you know when you are cross chaining? You will know the symptoms when the chain starts telling you about it, literally.

Video about cross chaining

The usual symptom is a rattling sound from the chain, caused by the chain rubbing against the derailleur body. In addition, a rattle could also come from the chain rubbing against the side of the next larger cog. You hear any of these rattles, you know you’ve gone over to the dark side. Don’t stay there too long! Those light rattles will slowly but surely eat away at your chain, derailleurs and cogs. Prolonged riding under cross chaining will weaken your chain, deform your derailleurs, and grind away the cog’s teeth, even knocking them off after some time. No dentist around to fix those broken teeth.

The drive-train of a geared bicycle is a complex and expensive system, and one which has a lot of demands placed on its performance. Cross-chaining is one of its worst enemies – don’t bring it with you when you ride!

Next post - Good shifting pattern (coming shortly since I'm crunching some numbers and figuring out some MS Excel tricks)

Cycling Gyan, Nugget 1

Understanding the cycle gears:

What is the use of gears ?

The gears are provided to decrease the pedaling effort and increase your efficiency.

CHAIN RING(S) – the toothed metal ring driven by pedal crank.

REAR COGS – toothed rings fitted to the rear wheel

CRANK SET – the chainring(s) and pedal crank together is referred to as CRANKSET

FREEWHEEL – the REAR COG assembly is referred to as FREEWHEEL

GEAR RATIO

• The effort required to pedal depends on the relative sizes of CHAIN RING and REAR COG.
• The GEAR RATIO is Number of teeth on chain ring divided by Number of teeth on rear cog 
•  Bigger the gear ratio harder it is to pedal

Most modern bikes come fitted with 2 or 3 chain rings and 6/7/8/9/10 rear cogs. The chain can be shifted to any chain ring and any cog, resulting in different gear ratios.

To make this clearer let us take an example; a typical mountain bike comes fitted with 3 chain rings with 42, 32 and 22 teeth chain rings and rear cogs with 14,17,19,21,23,25,27,29, 34 teeth (9 rear cogs, also called 9 speed)

FRONT GEAR NUMBERING

REAR GEAR NUMBERING

LARGEST GEAR RATIO

When you select FRONT GEAR as 3 and REAR GEAR as 7 you are selecting the largest chain ring (42 teeth in this case) and SMALLEST rear cog (14 teeth in this case) 

The selected gear ratio would be = 42/14 = 3, this is the largest gear ratio and hardest to pedal

SMALLEST GEAR RATIO

FRONT 1and REAR 1 would give the lowest ratio of 22/34 =  0.647, this is the smallest gear ratio and easiest to pedal. 

All the other combinations would give gear ratios between 3 and 0.647 

Selecting the appropriate gear

• Always ride in a gear that does not stress out the knee joints, start with the lowest possible gear and gradually shift to higher gear as you pick up the speed, keeping the pedaling rate more or less the same.
• In LOWER GEARS pedaling is easy, but Pedaling RPM (Revolutions Per Minute ) is high
• In LOWER GEARS your bike travels less distance per pedal revolution as compared to higher gear.
• In HIGHER GEARS pedaling is hard (if speed is low) and RPM is low
• In HIGHER GEARS your bike travels more distance per pedal revolution as compared to lower gear.
• On climbs in general use LOWER GEARING (pedaling should be easy, RPM high)

Coming up ! Nugget 2 - Proper Usage of Gears

Whe

The Bike Tune Up Workshop At Escapades

Ready for the TUNE UP

The one day Bike Tune Up Workshop at Escapades was a success, infact it turned into a BIKE OVERHAULING for Manoj. Manoj pedaled all the way from Corlim to Ponda covering a 20+ Kms one way. The workshop began at 10am with Donald, Jagdish, Raju, Hazrath, Anil and Me.

Fortunately (should I say unfortunately?) Donald’s bike had a flat in front tube, it was a first hands on experience for Donald in patching up the leak on the tube. 

Donald fixing a puncture

After the demo by me on Tuning of Deraillers (Front and Rear on Donald’s bike) it was Manoj’s turn to put his bike on the workstand. Manoj eagerly set to work on his bike and managed to get grease on his hands, shorts, t-shirt and where not.

Rear derailler clean up

With all the mechanics around we stripped the bike naked; wheels, deraillers, bottom bracket, fork and all. After cleaning thoroughly, the bike was assembled chiefly by Manoj with helping hand from Raju.

Rear Cogs Clean Up

 Within the span of 3 working hours, we managed to tune up one bike and overhaul another.

After the lunch, Manoj test rode the KHS ALITE 1000 trail bike and then rolled off on his TREK 4300 all smooth and shiny!

Smooth and Shiny....ready to Roll

Manoj Test Riding the KHS ALITE 1000

Escapades plans to bring many more workshops on BIKES and BIKING!