Convert 2 x 10 to 1 x10?
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Convert 2 x 10 to 1 x10?
After seeing the recent links to the sunrace and shimano wide ratio 10 sp casettes it's got me thinking about doing a conversion to 1 x 10.
I was thinking about going with s 11-42 shimano. My bike currently has a Shimano RD-M615 rear mech which I assume propably wasn't deisgned for for 42t cog but will it work? Had a bit of a look round but can't find any info to say one way or the other.
I was thinking about going with s 11-42 shimano. My bike currently has a Shimano RD-M615 rear mech which I assume propably wasn't deisgned for for 42t cog but will it work? Had a bit of a look round but can't find any info to say one way or the other.
- whitestone
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Re: Convert 2 x 10 to 1 x10?
Two of the Q&A on chainreaction says the medium cage version is fine for 11-42T.
Better weight than wisdom, a traveller cannot carry
- fatbikephil
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Re: Convert 2 x 10 to 1 x10?
It will work OKish if you wind the B-tension screw all the way in. For better results either get a Wolf tooth goatlink or better yet a one-up rad cage conversion.
Its also possible to drill and tap a new jockey wheel mount hole in the cage if you have the means.
Its also possible to drill and tap a new jockey wheel mount hole in the cage if you have the means.
Re: Convert 2 x 10 to 1 x10?
You can also get longer b screws. Google is your friend.
Re: Convert 2 x 10 to 1 x10?
Honest question - why convert?
I have only one 1x11 bike - and I hate it. The gears - not the bike! I LIKE being able to drop a bunch of gear ratios in a single change, and vice versa. I have 2x10, 3x9 and 1x11 - and of them the 1 by is my least favourite.If it had the mounting bits for a front mech I would convert to 2x10 which for me is the sweet spot.
What do people like about 1by systems?
I have only one 1x11 bike - and I hate it. The gears - not the bike! I LIKE being able to drop a bunch of gear ratios in a single change, and vice versa. I have 2x10, 3x9 and 1x11 - and of them the 1 by is my least favourite.If it had the mounting bits for a front mech I would convert to 2x10 which for me is the sweet spot.
What do people like about 1by systems?
- In Reverse
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Re: Convert 2 x 10 to 1 x10?
I've converted a couple of old bikes without putting a great deal of science into it - bought the front ring, played about with the rear mech and it was fine in both cases. Both Shimano, one XLS and one XT but I wouldn't think the Deore will fare any worse. Worst case you'll need to put a drive-side BB spacer in to sort the chainline.
What's to like about 1x? Plenty for me. The biggest thing is stronger legs - you're forced into a narrower range of gears, which usually means a slightly lower bottom end, which means stronger legs. Riding 1x all the time will give you stronger legs.
That then makes a massive difference across the rest of the gear ratios. These days having more than one ring up front is only a Rizla thickness away from having an e-bike.
Then throw in all the advantages of having less stuff on the bike - the saved weight of shifter/mech/etc; one less cable to snap/seize; one less derailleur to freeze in winter; more room on the handlebars (maybe squeeze in a controller for a wi-fi stove?).
Then there's fact that people will see you riding past on your 1x r!g and they'll just know that your seed is more virile.
1x
Based on my experiences none of that is necessary other than the B-tension screw bit. I've been able to change onto and off of the big cog just fine on a Sunrace 11-42 cassette without buying any extra bits for the bike.htrider wrote:It will work OKish if you wind the B-tension screw all the way in. For better results either get a Wolf tooth goatlink or better yet a one-up rad cage conversion.
Its also possible to drill and tap a new jockey wheel mount hole in the cage if you have the means.
With shimano shifters you can switch up to between 2 and 4 cogs in a single push, so on a wide-ratio cassette that negates the need for moving up or down a big ring at the front. You can convert from 1x to 2x without "mounting bits" if you're a swinger too.Clanton wrote:Honest question - why convert?
I have only one 1x11 bike - and I hate it. The gears - not the bike! I LIKE being able to drop a bunch of gear ratios in a single change, and vice versa. I have 2x10, 3x9 and 1x11 - and of them the 1 by is my least favourite.If it had the mounting bits for a front mech I would convert to 2x10 which for me is the sweet spot.
What do people like about 1by systems?

What's to like about 1x? Plenty for me. The biggest thing is stronger legs - you're forced into a narrower range of gears, which usually means a slightly lower bottom end, which means stronger legs. Riding 1x all the time will give you stronger legs.


Then throw in all the advantages of having less stuff on the bike - the saved weight of shifter/mech/etc; one less cable to snap/seize; one less derailleur to freeze in winter; more room on the handlebars (maybe squeeze in a controller for a wi-fi stove?).
Then there's fact that people will see you riding past on your 1x r!g and they'll just know that your seed is more virile.

1x

- whitestone
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Re: Convert 2 x 10 to 1 x10?
I'm in virtually the opposite situation. My only bike (out of five) with more than one chainring is my road bike. Well there's the singlespeed but that's a statistical outlierClanton wrote:Honest question - why convert?
I have only one 1x11 bike - and I hate it. The gears - not the bike! I LIKE being able to drop a bunch of gear ratios in a single change, and vice versa. I have 2x10, 3x9 and 1x11 - and of them the 1 by is my least favourite.If it had the mounting bits for a front mech I would convert to 2x10 which for me is the sweet spot.
What do people like about 1by systems?

In a way 1x is a sort of a singlespeed cop-out but you do get used to pedalling at a wider range of cadences. The "move across multiple ratios" argument isn't one that I find a problem. Looking at a gear calculator for a 2x system switching chainrings is roughly the equivalent of 3 ratios. Modern gear shifters are capable of doing a double shift with one press so you are almost there. Generally though looking ahead on the trail and getting ready for what's ahead is always the best option.
Front mechs are put through much greater stresses when switching rings purely because of the difference in size.
Despite being a 1x fan I don't agree with bike frames that don't allow you to fit a front mech. Choice isn't a choice when it's forced on you.
Personally I'd stick with what you like.
Better weight than wisdom, a traveller cannot carry
Re: Convert 2 x 10 to 1 x10?
It sounds like you've started down the path to true enlightenmentIn Reverse wrote: What's to like about 1x? Plenty for me. The biggest thing is stronger legs - you're forced into a narrower range of gears, which usually means a slightly lower bottom end, which means stronger legs. Riding 1x all the time will give you stronger legs.....
Then there's fact that people will see you riding past on your 1x r!g and they'll just know that your seed is more virile.![]()
1x


Adventure without risk is Disneyland - Bikemonger
Re: Convert 2 x 10 to 1 x10?
Some "interesting" replies. So much more to consider than I'd initially realised; the effect on my virility definitely wasn't on my radar
Grrrrrr!!!! Just lost the rest of my reply. Been typing for an age, not happy! Grrrrr!!!!
Will come back to this once I've calmed down. Grrrrr!

So, by winding in the longer b screw it pushes the mech back enough so the top jockey wheel clears the larger sprockets?Justchris wrote:You can also get longer b screws.
Google is evil; DDG is my friendJustchris wrote:Google is your friend.
Grrrrrr!!!! Just lost the rest of my reply. Been typing for an age, not happy! Grrrrr!!!!
Will come back to this once I've calmed down. Grrrrr!
Re: Convert 2 x 10 to 1 x10?
You can also put the b-screw in from the wrong side rather than getting a longer one
- whitestone
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Re: Convert 2 x 10 to 1 x10?
Yes. That's the whole job of the B-screw: to set the distance between upper jockey wheel and the sprockets. As Moder-dye notes you can put the screw in the opposite way round to push things further away but it's more awkward to adjust. The upper jockey wheel is also known as the guide pulley since it is what guides the chain from one sprocket to another when you change gear - it wants to be close enough to do its job but not too close to foul the sprockets.So, by winding in the longer b screw it pushes the mech back enough so the top jockey wheel clears the larger sprockets?
Better weight than wisdom, a traveller cannot carry
Re: Convert 2 x 10 to 1 x10?
What makes frames unsuitable for a front mech? Chainline? Bought a new frame and bit miffed that manufacturer specifies unsuitable for a front mech, might try it non the less and see.
- Bearlegged
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Re: Convert 2 x 10 to 1 x10?
I think the limiting factors will be chainring clearance around the chainstay, and tyre clearance around the front mech and/or chain.
Re: Convert 2 x 10 to 1 x10?
On Shimano rear mechs, if you take out the b screw, there is some times a plastic spacer underneath that can be removed so that you can increase the effective length of the b screw.
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Re: Convert 2 x 10 to 1 x10?
I used one of these Sunrace extenders (cheap) instead of a Goat link (pricey) when I needed to get a shimano mech to work with a bigger cassette:
https://www.merlincycles.com/sunrace-re ... forwardcss

Has worked well for me. Adjustment with the B screw wasn't enough to clear the largest cassette ring (might have been 9spd RM and 10 speed cassette).
I vaguely recall something about B screws, reduced chain wrap etc and it not being a good thing. Have no idea if this is true or just armchair commentary.
https://www.merlincycles.com/sunrace-re ... forwardcss

Has worked well for me. Adjustment with the B screw wasn't enough to clear the largest cassette ring (might have been 9spd RM and 10 speed cassette).
I vaguely recall something about B screws, reduced chain wrap etc and it not being a good thing. Have no idea if this is true or just armchair commentary.