Sunday, July 19, 2015

Upgrading the road bike into a Hill Climber

Wheels of Happiness

Rizal Philippines   July 18, 2015

The challenges of the Mt Province, Sagada and Banawe climb made me rethink and retooling myself to handle such difficult climb and I started reading researching about hill climbers bike. So the alternatives are:

1. Shift to an MTB, comes with a triplet and maybe an 11 to 36 gear (Shimano SLX or XT) This will be set you back by P20t.

2.  Buy a new crank with low gear preferably a triplet (I bought a Deore tirplet before 44 32, 22) precisely to hone up my climbing skills at Mahabang Parang (going to Antipolo)  I had one this all ready.  I spent P650 for a Shimano MTB bottom bracket outfitted to my Sars Bike. The mechanic mentioned he could not make the 44 work.  Fortunately for me I did. However, only two chainrings work because the STI for the rear has only 3 stops. (However I learned that the Sora had 3 stops

3. Buy the 105 ten speed 11 32 with long cage RD (this will se me back by P3,800.  2t for the RD and  P1.8 t for the gears.




Let us try to examine the advantages/disadvantages.

1.  Using the current triplet with 44 and 32 operational

   I am using a Shimano 105 with 10 speed casette, 12-13-14-15- 16 - 17- 19 - 21 -23 - 25 - 28.
   The gear inches for 44:    99 - 91 - 85 - 81 -74 - 70 - 62 -57 - 52 -47 - 40
    The gear inches for 32    72 - 66 - 61 - 54 - 50-  45 - 41 - 38 -34 - 30

    Let us compare this with   low gear of conventional gears:

    Say 28 gears

    39   x 28   -  37.6
    36   x 28   -   34.7
    34   x 28   -   32.7


I have two extra gear inches by using the 32 chain ring

Compare with 53 x 39 with  with 28 largest chain ring:

53      119 110 95 84 75 68 62 55 53

39        89 81 75 70 62 55 50 45  40

With 50 x 34

50      112 103 96 90 84 79  71 64 58 54

34       76 70 65 61 57 54 48  43  39 32.

With this, you can see that all the high gear and low gear of 53 x 39 chain ring can be had in  the 44. The lowest gear inches of 39 is the lowest in 44 gear at 28.

Using the  11 x 32 gear

44   37

32   27

22   19


53   41

39    33


50  54

34   27

It thus makes sense for me to have the triplet operational using the 12  to 28 shimano sprocket.  The advantagew would be mere 3 gear inches at most



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