Noob question about converting single speed gear ratio
#1
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Noob question about converting single speed gear ratio
Two months ago I got a new kilo WT after receiving suggestions from some of you on this bike. It's great so far, although the stock 48x16 gear ratio is a bit hard, especially on the few steep sections of my commute. I was thinking of converting it to something like 48x18, which people seem to suggest and which seems to be about my ideal gear ratio for the commute (as determined by comparing with my road bike).
My noob question is, how do I switch out the gear? Can I just buy a freewheel like this and swap it out with my old one?
Will I need to get a new chain too? Will I need any special tools? I've done cassette changes, chain changes, etc. on my road bike before, but never really did any work on my single speeds and want to make sure I'm not overlooking something stupid.
My noob question is, how do I switch out the gear? Can I just buy a freewheel like this and swap it out with my old one?
Will I need to get a new chain too? Will I need any special tools? I've done cassette changes, chain changes, etc. on my road bike before, but never really did any work on my single speeds and want to make sure I'm not overlooking something stupid.
#2
Old fart



Joined: Nov 2004
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From: Appleton WI
Bikes: Several, mostly not name brands.
That freewheel should be ok. Depending on how much room you have to move your wheel forward in the dropout slots, you may need to buy a new (longer) chain. If your chain does not use a master link, you may need to buy a chain tool. You will also need to buy the proper tool to remove your current freewheel, and possibly a different one to remove your new freewheel, should that become necessary.
#3
Grumpy Old Bugga
Joined: Oct 2006
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From: Adelaide, AUSTRALIA
Bikes: Hillbrick, Malvern Star Oppy S2, Europa (R.I.P.)
You're on the right track. Just change the rear freewheel and the one you've linked to gets lots of good mentions on here.
The chain question is a bit more problematic. I doubt you've worn it out in that time so the only issue is length. Because you're going to a larger rear cog, you will have to move the rear wheel further forward. If there's not enough room in the dropouts, you'll need a longer chain, but only by one link. The chances are though, you'll be right with what you've go so try that first.
You'll need a tool to remove the current freewheel. It tightens as you pedal and with the freewheel, you can't turn it backwards to spin it off, hence the tool.
Have a look through Sheldon Brown's single speed pages. They'll explain all.
You're lbs will be able to help.
In fact, I'd go one step further. It's obvious you're new to this so take your bike to your lbs and tell him what you need. Ask him to do the work BUT ask him if you can watch and have him explain what he's doing. Make sure you buy the bits from him - you are learning from him and he deserves some payback for that.
The chain question is a bit more problematic. I doubt you've worn it out in that time so the only issue is length. Because you're going to a larger rear cog, you will have to move the rear wheel further forward. If there's not enough room in the dropouts, you'll need a longer chain, but only by one link. The chances are though, you'll be right with what you've go so try that first.
You'll need a tool to remove the current freewheel. It tightens as you pedal and with the freewheel, you can't turn it backwards to spin it off, hence the tool.
Have a look through Sheldon Brown's single speed pages. They'll explain all.
You're lbs will be able to help.
In fact, I'd go one step further. It's obvious you're new to this so take your bike to your lbs and tell him what you need. Ask him to do the work BUT ask him if you can watch and have him explain what he's doing. Make sure you buy the bits from him - you are learning from him and he deserves some payback for that.
#4
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I just got an 18t white industries freewheel to go with my 48t chain ring. Its perfect for street riding imo. Have an LBS unscrew the freewheel for you. Its really quick and easy. You can also be ghetto and pound away with a flathead and hammer. You dont need a tool to put the new one on. Just hand tighten it and ride away. I also doubt you'll need a new chain.
#5
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Thanks all for your comments.
Below is a picture of how much space I have. Seems like a reasonable amount, eh? Though I'm not sure how much further I expect it to shift forward to accommodate the 18T -- suppose I still need enough free space to give the chain some slack when I want to remove the wheel.

Thanks for all the feedback. Shown below is my freewheel -- does anyone happen to know what tool I would use to get this particular one off?

Thanks. The White Industries freewheels look quite nice -- though I think I'll stick with the cheaper Shimano for now and perhaps upgrade later. Glad to hear that the ratio is working for you on the street.
I found this youtube video (https://www.youtube.com/watch?v=43i73xDBo9k) on removing and reinstalling a freewheel. Looks pretty easy, though he uses some cone wrenches and a vise. Should those be necessary? I have some large wrenches and a chain whip already. If all I need is a freewheel removal tool or so, and follow this guy's instructions, then it seems pretty easy. OTOH, I can also take it to the LBS as some have suggested, but the LBS I prefer is about 30 minutes away so it's a little bit of a pain.
You're on the right track. Just change the rear freewheel and the one you've linked to gets lots of good mentions on here.
The chain question is a bit more problematic. I doubt you've worn it out in that time so the only issue is length. Because you're going to a larger rear cog, you will have to move the rear wheel further forward. If there's not enough room in the dropouts, you'll need a longer chain, but only by one link. The chances are though, you'll be right with what you've go so try that first.
You'll need a tool to remove the current freewheel. It tightens as you pedal and with the freewheel, you can't turn it backwards to spin it off, hence the tool.
Have a look through Sheldon Brown's single speed pages. They'll explain all.
You're lbs will be able to help.
In fact, I'd go one step further. It's obvious you're new to this so take your bike to your lbs and tell him what you need. Ask him to do the work BUT ask him if you can watch and have him explain what he's doing. Make sure you buy the bits from him - you are learning from him and he deserves some payback for that.
The chain question is a bit more problematic. I doubt you've worn it out in that time so the only issue is length. Because you're going to a larger rear cog, you will have to move the rear wheel further forward. If there's not enough room in the dropouts, you'll need a longer chain, but only by one link. The chances are though, you'll be right with what you've go so try that first.
You'll need a tool to remove the current freewheel. It tightens as you pedal and with the freewheel, you can't turn it backwards to spin it off, hence the tool.
Have a look through Sheldon Brown's single speed pages. They'll explain all.
You're lbs will be able to help.
In fact, I'd go one step further. It's obvious you're new to this so take your bike to your lbs and tell him what you need. Ask him to do the work BUT ask him if you can watch and have him explain what he's doing. Make sure you buy the bits from him - you are learning from him and he deserves some payback for that.
I just got an 18t white industries freewheel to go with my 48t chain ring. Its perfect for street riding imo. Have an LBS unscrew the freewheel for you. Its really quick and easy. You can also be ghetto and pound away with a flathead and hammer. You dont need a tool to put the new one on. Just hand tighten it and ride away. I also doubt you'll need a new chain.
I found this youtube video (https://www.youtube.com/watch?v=43i73xDBo9k) on removing and reinstalling a freewheel. Looks pretty easy, though he uses some cone wrenches and a vise. Should those be necessary? I have some large wrenches and a chain whip already. If all I need is a freewheel removal tool or so, and follow this guy's instructions, then it seems pretty easy. OTOH, I can also take it to the LBS as some have suggested, but the LBS I prefer is about 30 minutes away so it's a little bit of a pain.
#6
Old fart



Joined: Nov 2004
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From: Appleton WI
Bikes: Several, mostly not name brands.
Shown below is my freewheel -- does anyone happen to know what tool I would use to get this particular one off?
#7
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Possibly this Shimano 4-prong tool:
#8
Veteran Racer


Joined: Jul 2009
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From: Ciudad de Vacas, Tejas
Bikes: 34 frames + 82 wheels
Nah, he'll be fine. The axle will only move about 1/4 inch forward in the dropout.
#10
Grumpy Old Bugga
Joined: Oct 2006
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From: Adelaide, AUSTRALIA
Bikes: Hillbrick, Malvern Star Oppy S2, Europa (R.I.P.)
Those removal tools aren't expensive and you only need the right sized spanner as well. Well worth having in the tool box.
As TT says, 2 teeth = a quarter inch, you'll be fine (the chain will move 1/8th inch for each tooth).
As TT says, 2 teeth = a quarter inch, you'll be fine (the chain will move 1/8th inch for each tooth).
#11
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I'll update this thread with anything as I try it next week once I get the parts, even if nothing goes wrong just in case it's helpful to other newbies.
Last edited by Gamma Point; 04-12-14 at 08:28 AM.
#12
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Joined: Apr 2014
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From: Los Angeles
Bikes: KHS Gran Sport fixed gear conversion.
I would find it immensely helpful as I am considering the same thing, but in reverse (going from a 16 tooth sprocket to a 15 tooth). A post mortem with pictures would be appreciated!
#13
Grumpy Old Bugga
Joined: Oct 2006
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From: Adelaide, AUSTRALIA
Bikes: Hillbrick, Malvern Star Oppy S2, Europa (R.I.P.)
This is actually the most rational use of a flip flop hub. Stick the 15 on the other side but leave the 16 on so you can change it around while riding or easily change it after a ride. Using both sides this way is a good way of fine tuning what gearing you want because eventually you'll reach a point when you realise you aren't changing the wheel around - that's often a good time to remove the superfluous cog.
#14
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Sure thing bud. I'll try to take pictures of anything that looks like it might be useful, and will summarize how things went. I expect I'll get my freewheel removal tool late this week.
#15
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From: Los Angeles
Bikes: KHS Gran Sport fixed gear conversion.
This is actually the most rational use of a flip flop hub. Stick the 15 on the other side but leave the 16 on so you can change it around while riding or easily change it after a ride. Using both sides this way is a good way of fine tuning what gearing you want because eventually you'll reach a point when you realise you aren't changing the wheel around - that's often a good time to remove the superfluous cog.
This gear ratio is fine for me as far as commuting and generally poking around downtown goes but I would like something a little more intense for fun. I actually have a geared Schwinn which I now never ride since I got the fixie. I never thought I'd like fixed but I LOVE it.
#17
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Alright, I got my Park FR-6 removal tool in the mail today, so I did the switch. It was ridiculously easy, and this guy already has a perfect write-up of the procedure.
But in any case, I promised some description so here it is. I figure I've done a good job in my BF posts to show that I'm completely devoid of any secret bike mechanic skills, so perhaps me saying how easy it was will give the rest of you confidence.
First, I put the removal tool on the freewheel (securing it with the nut):

Then, I just grabbed a big wrench and put it around the tool:

You turn counterclockwise to get it off. It took a decent amount of force (so much that I thought "is this going to come off?", but then I just decided to take it off like a boss).
Here's a picture of the new Shimano 18T next to the bikes direct factory-installed Dicta 16T:

I then just used some bike grease on the threads on the wheel and on the inside of the new freewheel and just screwed it on. It was easy:

And here's the new cog on the bike:

You can compare the above pic with one earlier in this thread to see how much the wheel will move forward upon going from a 16T to a 18T.
I just took the bike out for a test ride around the block and think 18T was the right decision -- much more enjoyable to ride than the 16T, but still plenty of gearing to go fast when needed.
The one downside with getting this Shimano cog is that apparently it takes some special Shimano tool to remove. So now I need to get one of those...
But in any case, I promised some description so here it is. I figure I've done a good job in my BF posts to show that I'm completely devoid of any secret bike mechanic skills, so perhaps me saying how easy it was will give the rest of you confidence.
First, I put the removal tool on the freewheel (securing it with the nut):
Then, I just grabbed a big wrench and put it around the tool:
You turn counterclockwise to get it off. It took a decent amount of force (so much that I thought "is this going to come off?", but then I just decided to take it off like a boss).
Here's a picture of the new Shimano 18T next to the bikes direct factory-installed Dicta 16T:
I then just used some bike grease on the threads on the wheel and on the inside of the new freewheel and just screwed it on. It was easy:
And here's the new cog on the bike:
You can compare the above pic with one earlier in this thread to see how much the wheel will move forward upon going from a 16T to a 18T.
I just took the bike out for a test ride around the block and think 18T was the right decision -- much more enjoyable to ride than the 16T, but still plenty of gearing to go fast when needed.
The one downside with getting this Shimano cog is that apparently it takes some special Shimano tool to remove. So now I need to get one of those...
#19
Grumpy Old Bugga
Joined: Oct 2006
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From: Adelaide, AUSTRALIA
Bikes: Hillbrick, Malvern Star Oppy S2, Europa (R.I.P.)
Dammit, I wanted to charge the local hipsters $100 to do this, now they'll all be doing it themselves. 
Doing your own work leaves a good feeling doesn't it

Doing your own work leaves a good feeling doesn't it





