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About three months ago I bought a second hand bike for £70; to be honest it is reasonably good. Current setup for gears is a 2 x 18 (38-48 front, 13-28 rear).

As far as I can tell it's not a branded Shimano system, just some generic Shimano 8 speed (the shifters say ST-2200 and the RD looks like the RD-2200).

I want to upgrade the bike as I keep having to re-index the RD, and I think it's just worn and sluggish. Also I want a cassette with a larger low gear (maybe a 30) as I have a big hill by my house and I struggle to get up it.

I was thinking as Wiggle has a sale I would upgrade to Shimano CS-HG41 8-Speed Cassette 11-30T and Shimano Sora R3000 9 Speed Rear Mech. I was thinking of possibly changing the 38 chainring to a 36 or even a 34.

I ride 8miles to work and back 4 times a week (64miles a week) with a backpack for food and clothes, and as I said the bike isn't too bad, I just want the hills to be a bit easier.

Would the above new setup be ok, or is there a better way of me achieving this?

I have added a link to a bike calculator for my hopeful setup.

http://www.gear-calculator.com/?GR=DERS&KB=38,48&RZ=13,14,16,19,20,22,24,28&UF=2150&TF=80&SL=2.5&UN=MPH&DV=teeth&GR2=DERS&KB2=36,48&RZ2=11,13,15,17,20,23,26,30&UF2=2150

Thanks for any responses.


I had a look and the smallest cog does have another set of holes about 65mm in diamater. Also the holes on the current smalles chainring are 125mm.

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    You wont notice much difference going from a 28t to 30t cassette, it is only half a gear different. Instead I would look at options to replace your inner chainring with a 32 or 34 ring (if you can get one that fits) – Andy P Aug 7 '18 at 12:20
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2200 is the Shimano Claris line from 2009, so not 'unbranded', but at the bottom end of Shimano hierarchy.

Firstly, the derailleur itself is probably not causing shifting issues. Replacing the shift housing and cable will very likely fix the shifting and keep the indexing properly adjusted. Check chain and cassette wear as well.

A 9 speed Sora derailleur with a 8 speed cassette and Claris 8 speed shifter should in fact work. The reason is that all Shimano road rear derailleurs and shifters at 10 speed and below generally use the same cable pull ratios. You can also consider the Claris RD-R2000, which will work a little better than the RD-2200.

The RD-R3000 and RD-R2000 will work with a cassette with a large sprocket up to 34 teeth.

The 48/38 crankset is a bit weird. Fitting a smaller ring depends on the bolt circle diameter (BCD) of the crank. What has probably happened is that a previous owner has fitted a smaller big ring to a 130mm BCD crank which limits the small ring size to (usually) 39 teeth. If the BCD is 110mm, you'll be able to go to a 34 tooth small ring at least.

Remember that if you do change the cassette you'll need to replace the chain as well.

Edited to add: There is another route to a drivetrain with a spread of ratios - buy a different used bike that has what you want (and re-sell the current bike). This is my standard advice in these situations as upgrades can easily cost a significant fraction of the original cost of the bike, and entail headaches and frustration.

  • 48/38 could be a CX specific crankset, although they are more commonly 46/36. It could also be a 48/38/28 with the inner ring removed. – Andy P Aug 7 '18 at 12:23
  • Think there is also one caveat on the pull ratios. I believe Tiagra 10 speed is not compatible with other setups. – Andy P Aug 7 '18 at 12:26
  • Yes that is true, it uses 11 speed pull ratio. – Argenti Apparatus Aug 7 '18 at 12:28
  • I had a look and the smallest cog does have another set of holes about 65-70mm in diamater. Also the holes on the current smalles chainring are 125-130mm (so I am assuming 130mm) – Nat Aug 7 '18 at 13:01
  • @Nat, not sure what you mean about the smallest cog. Looks like I was correct about the 130mm BCD crankset. Old cheap bikes typically have a 130mm crank. You can get a used 110mm crank reasonably cheaply (but it'll cost a significant fraction of what you paid for the bike). I snagged a brand new but with cosmetic issue non-series Shimano crank 50/34 crank for $45 US off Ebay a while ago – Argenti Apparatus Aug 7 '18 at 14:16
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Also I want a cassette with a larger low gear (maybe a 30) as I have a big hill by my house and I struggle to get up it.

So get new tires and if money does not matter, get new wheels. these are updates, which you will feel the most.

in case you have a suspension fork, get a rigid fork. this will save weight and you get the hill up a lot more easier.

The first update you should invest is definitely a new pair of tires!

  1. Tires
  2. a new chain + new cassette
  3. rigid fork if you have suspension
  4. shifting components
  5. wheels (big difference, but likely expensive)
  • At that point, one may as well just sell the current bike and get a new (used) bike. – RoboKaren Aug 29 '18 at 16:33
  • yes, but the first two points are low-budget and have a great effort. well pumped up new tires, new chain + new cassette and your bike will feel new, so these investments are definitely worth it. – bucky Aug 30 '18 at 8:07

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