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Monday, May 17, 2021

Upgrades of two MTBs complete - mostly Do It Yourself

Wheels of Happiness

Rizal Philippines
5.15.2021










This post has completed all the planned upgrades of his MTB - mostly done cheap and at hisi own effort.  This reflects the higher level of technical skill, and the longings of a bike rider to be better everyday - indeed fulfilling one of our mandates as a creature and as a creature.

The upgrades where:
1.  Bigger cogs from 11-36 to 11 - 42.;   for added lower gears in ascent/climbs
2.  Bigger front disc rotor from 160 to 180 mm for greater braking power
3.  Two by set up from 3 by using Deckas chain ring.

The upgrades were a result of seeing a barrage of ads at a social media and e commerce platform; tantalizing you with their cheap price and availability and how these stuff will make you look better.

1.  Cogs -  I bought the S brand from an on line seller a biker too;  He told me his experience that the installation is straightforward - remove the old cog using the cog removal tool, install and presto.  No need for goat link or additional chain link (for as long as you have long cage RD).  No need to adjust the rd settings.   It cost me P1,000 each.   I bought two.   True enough the installation was simple and straightforward.  No need to go to mechanic if you have crank removal tool.

The move gives you added 6 teeth (from 36) and other power when in difficutl climbs (say Mahabang Parang or quarry road)  and gets your bike ready for one by.

2.  Brakes - for extra braking power.  I was first tempted to buy quad piston brakes which cost P3k for a W brand and no less than P12K for an S brand.  But other riders said that gains can be minimal because only 30% of brake pad area is increased;  the brake pad is costly;  uses a lot of oil, is difficult to bleed.  The cost differential is about 500%

And so this post opted for the increase of braking area from 160 to 180 mm.   The cost is very minimal.  One floating disc 180 mm 3Pro is only P400.00 plus the adapter priced at P143 each.  

The process is again simple and straightforward.  Remove the old disk using a Torx tool (number T25)  This is where my tool box of 46 pieces came in handy.  The torx screws could not be removed with handheld tool.   They were tough screws to remove.    Then replace the disk rotor after carefully cleaning the disc hole of oil and grime.   The fiddly thing is the adjustment of spacers   And centering the brakes.   

3.   Two by set up.    This post ordered Deckas chain ring with wide narrow teeth; 34 t  I will do the two by because it has wider range (since you retain the 24 granny gear) and literature at the net says it is the best set up and is longer lasting 

  As for the gears, at 34 t front chain ring and 10 cogs at the rear, you achieve a high end gear inches of 34/10 =  3.4 x 29 =  98.6  nearly same ratio of a road bike with 50 x 12. = 41.66 x 27  =   112.   I would have achieved this with 36 front chain ring   3.6 x 29 = 104.4 (No wonder  29ers even with one by are fast).  

For the low end using a granny (24t)  I would achieve  24/42 = .57 x 29 (a super low2 gear).  Even at 34, the low end ratio would be .809  (less than one)

There is dearth of literature on 2by set up;   even mechanics and other rabid MTB could not say much on the 2bys system (we are just following the RB set up)  But I am confident of the fact that when
I have to have a much lower gear (lower than one offered by one by) I could always count on a granny
chain ring.  I have seen many elderly who went on an outwardly looking one by but had a reserve 24 chain rin,  

The process is more complicated.  

      1.  Remove the crank set from the BB.  Remove the pedal for ease of work
      2.  Remove the chain ring.  It is more difficult for the xt because the old model crank requires
           that you counter the counter sink nut with a stopper (they say you can use a screwdriver but
           it keeps on slipping) And you need a T30 torx (glad I had the toolbox with torx set).  Initially
           this post thought this required at  T25 or T27.  But the T30 is perfect.

     3.  Next step is to determine the the placement of the Deckas 34 T.   Initially I thought this would 
           be outside of the spider.  But this would be far away from the 3rd gear (the 24t) and this would
           position the chain ring at the former location of 42t.  Initiallly this post thought that the  XT 
           will not accept the Deckas.  

           But installing this behind the spider would be perfect fit:    It would be in the 2nd position of 
           the FD shifting;  and near the 24t (the #1)

     4.  And so this post thought so  But he protrusion of the crank bolt caused the chain to jump 4x
          every revolution  Rather than filing or sanding the protrusion, the post reversed the installation
          of the crank bolt  - with the flatter head on the inside and the protrusion on the outside.  Not 
          good looking but its the cheapest solution.   

    5.  And then adjusting the FD.

        1.  Screw in the high limit screw (at the outside) all the way in so that you cant shift to #3, and
              have the chain fall off.

       2.  Loosen the low screw so that the chain will fall off to Number 1. (the grannie).  You have to
            to make the adjustment, because the chain ring Deckas being wide narrow will not cause chain
            fall off on the lower gear.   The adjustment will bring the chain guide to the farthest end and the
            therefore the shift to take place.  

All in all the upgrade cost me (for the two MTB)
  
     1.  Cogs S brand   11 - 42   @ P1,000  x 2                                            2,000.00
     2   Deckas    round, 34t  @ 290 x 2                                                          580.00
     3.  3 Pro 180 mm rotor    @ 440 x 2                                                         880.00
     4.  Adapter     143 x 2                                                                                286.00
     5.  Tool box 46 pcs                                                                                    280.00

                                                                  Total                                           4,026.00
     
One kapdyak  I know spent P4,000 on the Sunrace cogset alone   My cost covered 3 upgrades:

    1.  Cogset
    2.  Braking system
    3.  Two by set up

My cost is a mere 1/4 of a quad piston, or 1/5   SRAM or Shimanao upgrade kit.  (about P20K)

The results on my riding?

     I could not tell much now. 

    1.  For the 11 - 42 - effortless riding;
    2.  For the braking system - I am still bedding them in.
    3.  For the two by set u -  lighter by a few hundred grams.  Great cosmetic.
         Unless I hit the trail, I would not be able to appreciate the benefits of a two or one by system

         Again, my upgrading is a result of:
   1. Desire to being better, or desire for having a better set up;
   2.  Being competitive with other fellow bikers.
   3.  Being a sucker for ads (being  marketing man)

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