Green_Frog

I am trying to find out what it is I need to do to covert my 3x8 to a 2x8 on my specialized pitch. Any help or direction would be greatly appreciated. Thanks.

dabac

Stop shifting to the Granny gear. Done.

Really, unless your crankset is worn to the point of needing replacing anyhow, going from 3x to 2x is a considerable cost/effort with very little gain.
Apart from being able to say "I run 2x".

To make it work like it'd been built as 2x you need a new crankset, maybe a new BB, possibly a wider range cassette, and a new shifter.

Nao_lin

i mean i can see a few minor reasons to do this. I had an older bike where the front derailleur was broken and having issues shifting in and out of the granny gear and since i didn't use it and I didn't feel like putting any money into the bike i just re-adjusted the front derailleur so i couldn't even shift into the granny gear and just removed the chain ring.

This was even more important since my GF at the time used the bike and even though I told her to stay away from the granny gear she would just shift into it by mistake and just removing the option helped her stop having the mechanical issues.

But if your doing this on a bike without mechanical issues, apart from the very tiny weight removal there isn't much point.

O.. so to answer your question, you just have to remove the chainring and re-adjust your front derailleur. I was able to remove the chain-ring without having to remove the cranks so it took me literally like 5 minutes. You can look up videos on you tube on how to adjust a front derailleur if you don't know how.

fietsbob

Consider a 2 speed internally geared crank (patterson metro, the gear shift is instant at any speed)
its 28t (for high ground clearance), has a 1.6X overdrive.. to act like a 45t as the chainring turns faster than the crank arm.
https://www.pattersonbike.com/
Sram has a couple others (Not latest gear!! featured), with 24 t chainring, for like a '38.5 t' high gear.. https://www.sram.com/truvativ/produc...3exddd64cpjyng
they come with the BB as part of the Mech, with a cable operated shift lever on the HB.

No FD no shifting delay even if stopped.

MRT2

My son installed a chainguard on his mountain bike. Now instead of a 3 X 9, he has a 2 X 9.

Canker

The only thing you might need is some spacers/washer for the chainring bolts.

Kapusta

Are you looking to just drop the big or small ring, or go with entirely new ring sizes?

A lot of people have done a conversion because they don't really need their big ring, so they just run the small and middle ring. In fact, before 2x10 came out, 9 MTB 2X cranks were mostly just 3X cranks with the big ring replaced with a bash ring.

If that's what you want to do, you can replace the big ring with a bash ring. BBG makes good ones that are very cheap (like ~$20 shipped): https://www.bbgbashguard.com/

Then turn in the high-limit screw on the front derailleur to keep it from shifting into the big ring position.

Then you shorten the chain using the middle ring as the new "big" ring for sizing the chain length. This step is REALLY important because this is (IMO) one of the real benefits to running a 2x drive-train: A shorter chain which means less chain flopping around and much fewer dropped chains.

I have done this on all my 8 and 9 speed mountain bikes since 2001. I just don't need the big ring on trails. The only place I spin out is either on pavement or really fast, wide open fire roads. It is easier to keep a 2x setup shifting well. I have changed the 32t middle ring to a 34t or 36t on some setups, but even the 32t with an 11t small cog in the back seems to do fine for me. On my current 2x9 I went with a 24t small ring and 36t middle ring.

Green_Frog

Thanks for all the input. I will put your advice to the test, and see what works best. Thanks again and I appreciate the advice.

MRT2

Here is an even cheaper option. This is the one I got for my son. Got it for maybe $10 on one of those 25% or 30% off sales.

Bike Chainrings for improved gear shifting | Bike Nashbar

My son only uses his mountain bike for single track anyway, as around town he rides a vintage road bike.

MisterK

I personally run 1x8 on my commuter/grinder.
If i needed any wider ratio maybe id consider 1x9.
Front derailleurs ugh......

Kapusta

Doubt it is cheaper when you include shipping.

BBG comes with a lifetime warranty. Pretty much any size or tooth count you want. Made in the US. One man operation.

Nashbar sucks. I do buy stuff from them, but there needs to be a REALLY good reason for me to do it.

bikeme

Some newer front shifters have a 2x or 3x switch so you don't have to by a new 2x shifter.

Kapusta

If he is doing a 2x conversion using his 3x crank, then any 3x shifter will work. You simply don't use one of the shifts.