Month: May 2021

MTB Repairs: Adjusting Your Rear Derraileur

I have a Shimano SLX M7000 rear deraileur that I have been battling with.

I found an excellent video from parktool on rear deraileur adjustment that I use as the basis of my repairs.

Always make sure derailler is straight and secure on the bike - otherwise the below will not bare any fruit. This needs to be repaired first.

Step 1: Setting the H-limit screw

This is setting the limit on the smallest sprocket on the rear cassette.

  1. Shift into smallest sprocket - all the clicks
  2. Wind barrel adjuster in towards the shifter - clockwise facing the shifter from the cable
  3. Switch off clustch
  4. Jockey wheels must be lined up veritcally under the sprocket - holding the lower cage down gives a good position sitting at the back of the bike
Limit set incorrectly not aligned correctly
After h-limit screw has been set and sprocket aligned

Step 2: Set the L-limit screw

  1. Shift into highest sprocket (easiest gear)
  2. Wind barrel adjuster in towards the shifter - clockwise facing the shifter from the cable
  3. Switch off clustch
  4. Jockey wheels must be lined up veritcally under the sprocket - holding the lower cage down gives a good position sitting at the back of the bike

    • then do the biggest sprocket
    • then do b-tension screw
    • 11 speed - 46T - 8 or 9 mm
  5. correct cable tension
    • pull it to be taught
    • hold derailler cage to reisist it moving
  6. index the gears

    • start in the smallest

    • put it up then go back down

    • do for the first 3

    • if there is too much tension it will go up 2 or 3 gears - not just the one

    • use barrel adjuster a quarter at a time

    • move barrell adjsuter anti-clockwise facing the shifter from the cable

    • barrel adjuster - clockwise adds slack (moving shifting positions outward) - anti-clockwise - tightens

Cool things to see and do on a bitcoin node

Here is a list of cool things you can see, do and find out on a bitcoin node. Specifically for full nodes running in CLI or daemon mode - not GUI client.

Get Block Count

Get the total number of blocks in your version of the blockchain - the one on your local node. If it is up to date then this will be the number of blocks in total verified on the bitcoin blockchain.

bitcoin-cli getblockcount

Get the total amount of bitcoin that has been mined

To check the total amount of bitcoin that has been mined execute:

ubuntu@btc:~$ bitcoin-cli gettxoutsetinfo
  "height": 713513,
  "bestblock": "00000000000000000000e786c548255af5b4509c16d909b03c65568dc4ab998a",
  "transactions": 46621408,
  "txouts": 77012436,
  "bogosize": 5761235215,
  "hash_serialized_2": "4edfcd9e471794a587ac32dd26d2285829b89d0999ab4740391593bc7358a63c",
  "disk_size": 4705170290,
  "total_amount": 18896756.29158394

The "total_amount": 18896756.29158394 is the total from the max of 21000000

Get the time (in UTC not blockheight) a block was mined

Get the hash, get the block verbosely and convert the unix epoch time into human readable. Use the mediantime.

Mediantime is the median time of the past 11 block timestamps

bitcoin-cli getblockhash 100000
bitcoin-cli getblock 000000000003ba27aa200b1cecaad478d2b00432346c3f1f3986da1afd33e506 2
date -d @1293622620
Wed 29 Dec 2010 11:37:00 AM UTC

Some dates:

  • block 100,000: Wed 29 Dec 2010 11:37:00 AM UTC
  • block 200,000: Sat 22 Sep 2012 09:57:08 AM UTC
  • block 300,000: Sat 10 May 2014 05:54:38 AM UTC
  • block 400,000: Thu 25 Feb 2016 03:52:57 PM UTC
  • block 500,000: Mon 18 Dec 2017 06:14:46 PM UTC
  • block 600,000: Fri 18 Oct 2019 11:09:37 PM UTC
  • current blockcount 695599: Fri 13 Aug 2021 06:00:35 PM UTC

The number of blocks per gregorean year:

365 days * 24 hours * 6 blocks an hour

Get the Genesis Block

Get the block hash at height 0:

ubuntu@btc:~$ bitcoin-cli getblockhash 0

Verbosely get the block by the hash:

ubuntu@btc:~$ bitcoin-cli getblock 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f 2
  "hash": "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f",
  "confirmations": 695440,
  "strippedsize": 285,
  "size": 285,
  "weight": 1140,
  "height": 0,
  "version": 1,
  "versionHex": "00000001",
  "merkleroot": "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b",
  "tx": [
      "txid": "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b",
      "hash": "4a5e1e4baab89f3a32518a88c31bc87f618f76673e2cc77ab2127b7afdeda33b",
      "version": 1,
      "size": 204,
      "vsize": 204,
      "weight": 816,
      "locktime": 0,
      "vin": [
          "coinbase": "04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73",
          "sequence": 4294967295
      "vout": [
          "value": 50.00000000,
          "n": 0,
          "scriptPubKey": {
            "asm": "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f OP_CHECKSIG",
            "hex": "4104678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5fac",
            "type": "pubkey"
      "hex": "01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff4d04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73ffffffff0100f2052a01000000434104678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5fac00000000"
  "time": 1231006505,
  "mediantime": 1231006505,
  "nonce": 2083236893,
  "bits": "1d00ffff",
  "difficulty": 1,
  "chainwork": "0000000000000000000000000000000000000000000000000000000100010001",
  "nTx": 1,
  "nextblockhash": "00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048"

Decode the hex field - with the iconic Chancellor on brink evidence

ubuntu@btc:~$ echo “01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff4d04ffff001d0104455468652054696d65732030332f4a616e2f32303039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f6e64206261696c6f757420666f722062616e6b73ffffffff0100f2052a01000000434104678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5fac00000000” | xxd -r -p
????M??EThe Times 03/Jan/2009 Chancellor on brink of second bailout for banks?????*CAg????UH'g?q0?\֨(?9 ?yb??a޶I???L?8??U???\8M??

Get Info

There are a few ways to get information

bitcoin-cli help | grep info
gettxoutsetinfo ( "hash_type" )
getmemoryinfo ( "mode" )
getaddednodeinfo ( "node" )
getdescriptorinfo "descriptor"
getindexinfo ( "index_name" )
getaddressinfo "address"

Fruit Juices to Avoid in South Africa

Some juices contain terrible substances and fake sugar. Others are 100% pure fruit juice and are good for the body.
Let us separate the bad juices from the good.

Avoid these Fruit Juices

The first thing that should stop you buying is that it does not say 100% pure fruit juice. If it does not say that the juice should be avoided. Below are the brands to avoid.

  • Fruitree (Pioneer Foods Group) - Acesulfame K, Sodium saccharin, Sodium Cyclamate and flavouring.

Do not ever purchase or drink Pioneer Foods Group "Fruitree" fruit juice product. It is very dangerous with short term and long term health affects.

Bad Ingredients

  • Acesulfame K - headaches, depression, nausea, mental confusion, liver effects, kidney effects, visual disturbances, and cancer in humans
  • Sucralose - bloating, nausea, wheezing, itchy, runny now, anxiety
  • Aspartame - headaches, dizziness, depression, increased hunger, depressoin
  • Sodium saccharin - bladder cancer, headaches, breathing difficulties, itching, diarrhea
  • Sodium Cyclamate - cancer causing - banned in the USA
  • Neotame

These are fake sugar. They have the taste but none of the natural sugar needed to give energy to the body. Hence the heart rate is increased however there is no fuel backing it. You will be in danger of over exertion.


Notice how the 40% wording does not stand out - it is not clear at all


Good Fruit Juices

  • Pure Refresh - Acidity regulator and flavouring