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Post deleted by ginofairplay
Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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I put on a MTN bike derailleur on my 10 speed bikes and it works fine. I did this back in 2009 when it was hard to find a 11-34 so I bought an off brand cassette made for tandems but changed to Shimano when they came out with 11-34. I put on a new chain as well. My bike shifts just like it did with the derailleur it came with the bike.

I remember vaguely that I had to make sure the pull ratios were the same.

I did this to two bikes both 10 speeds one from 2005 and another from 2010. It helped me keep my power in check when climbing in doing IMC. I used to swap back and forth rear derailleurs but after awhile I just kept with the MTN because easier gears where nice for hills.

PM if you want me to look more carefully or take photos.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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ginofairplay wrote:
Hello,
I am wanting to put better climbing gears on my road bike. I realize there's compact cranksets, but I prefer having a standard chain ring. That being said I'm looking to put a long cage mountain bike rear derailleur and a 11-34 rear cassette.

I was at a local bike shop talking to them about doing this. They told me I can't buy a 10 speed rear derailleur,needs to be a 9 speed with a 11-34 rear cassette. I said you sure the bike it's going on is a 10 speed bike, not 9.

Does this sound right?

Also if changing rear derailleur to mountain bike will it change the shifting , meaning on a 105 shifter the inner switch which normally would shift down to a hard pedaling gear will it be now opposite?

Thank you for your time

Your bike shop is right. With introducing 10 speed Shimano has changed pull ratio and their RD and MTN group are not interchangeable anymore.
You have to understand that shifting is actually happening in the shifters not in derailleur that is why pull ratio is important.
So yeah, you have to use 9spd RD on road 10spd group, which have almost the same ratio. Users report working with M772 XT RD or M591 deore (I have the last combination and it works ok).
You also have to be careful if you have new Tiagra shifters (4700). In that case this combination will not work together since Shimano has changed pull ratio for Tiagra (it similar to 11spd).

I don't understand the last part of your question.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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ginofairplay wrote:
Hello,
I am wanting to put better climbing gears on my road bike. I realize there's compact cranksets, but I prefer having a standard chain ring. That being said I'm looking to put a long cage mountain bike rear derailleur and a 11-34 rear cassette.

I was at a local bike shop talking to them about doing this. They told me I can't buy a 10 speed rear derailleur,needs to be a 9 speed with a 11-34 rear cassette. I said you sure the bike it's going on is a 10 speed bike, not 9.

Does this sound right?

Also if changing rear derailleur to mountain bike will it change the shifting , meaning on a 105 shifter the inner switch which normally would shift down to a hard pedaling gear will it be now opposite?

Thank you for your time

SRAM or Shimano?

For Shimano they are correct if you are running an MTB cassette.
Things changed with cross-compatibility between Road and MTB when when 10 speed arrived.
Apparently 10 sp MTB cassettes are 1mm wider than their road counterpart, so it will be close but not good (friction losses).

Hence I was also advised to use a 9speed MTB rear mech and MTB cassette with 10 speed road shifters.
.
And since the 9 speed mech. was cheaper and the setup worked flawless, I didn't dig any deeper.
...
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Re: A question about putting MTN bike derailleur and cassette on road bike [matotato] [ In reply to ]
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Thanks for confirming what the ship said was indeed accurate. As for the 2nd part of it. Will both shifter operate the same when shifting? Many year ago I did this only to find that the shifter were basically backward the long arm on the shifter instead of pushing it inwards to ask for the gear to up to an easier gear it would go down. I hope I did a better job of expelling this time around.

Gene
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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I get what you’re saying on your second part - you’re talking about the old “rapid rise” rear derailleurs. In short yes, you’ll be fine and everything will shift normally. Rapid rise derailleurs have luckily died the death they deserve.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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Just FYI, the new 11 speed R8000 group from shimano will handle an 11-34.

In fact it will also do a 40 tooth cassette

https://www.youtube.com/watch?v=roUXWvAN-9k
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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I'm curious about the choice to avoid the compact crankset. Depending on your current crankset, it might just be chainrings, but in reality, you can score a nice-enough compact for less than the cost, including hassle, of switching out all that rear stuff. Would slide right in, adjust the FD height and limits, and good to go.

But mostly I'm curious. If you want a better climbing gear, what's the downside to a compact? "I don't want one" is an acceptable answer I suppose!

Matt
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Re: A question about putting MTN bike derailleur and cassette on road bike [Emma'sDad] [ In reply to ]
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Hey Matt,
I'm getting up there in age and just moved and everywhere I will ride is hill after hill. I have thought about compact but for these reasons I want to stay with a standard cranks. I will have to purchase crankset, a rear derailleur that will accomadate a 11-32 cassette, a chain ,basically 4 pieces. With going in the direction I asked about it's 3 pieces I will be buying. I do also want the 53 chainring for flats verses the 50.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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Have you analyzed the difference in speed from 53 crank to 50? Say top line rpm is 110. Suggest using the Sheldon brown calculator.
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Re: A question about putting MTN bike derailleur and cassette on road bike [fat] [ In reply to ]
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Yes I have. I would be replacing crank, chain, cassette, derailleur. Keeping my standard crank 3 pieces
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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I think a compact crank might work, or even a mid compact 52-36.

Look into this to potentially use your existing rear derailleur and a bigger casette.
https://www.wolftoothcomponents.com/...in/products/roadlink

Or this will let you use your shifters with a MTB rear derailleur.
https://www.wolftoothcomponents.com/...rain/products/tanpan
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Re: A question about putting MTN bike derailleur and cassette on road bike [Rumpled] [ In reply to ]
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Thanks. I want as close to a triple crank set up as possible. My current short cage 105 will only accept max 28 tooth correct? If this indeed correct 28/36 is not quite what I'm looking for. My plan is to stay with my current crank 53/39 and put a long cage rear derailleur and put a 11-34 cassette and have.a
34-39 set up, almost a triple.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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What cassette do you have now?

What rear d do you have now?
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Re: A question about putting MTN bike derailleur and cassette on road bike [fat] [ In reply to ]
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a 105 rear derailleur. a rear 11-28 cassette.
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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Your current rear derailleur will run a 30T along with the wider range full compact chainset.

You will loose half a gear on the top end but gain a 34 X 30 climbing gear on the bottom which is just lower than the 34 you seek.
The compact will allow tighter gear spacing by running 12-30T cassette.

Here is a good visual for you.

http://www.gear-calculator.com/...6,30,34&UF2=2135
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Re: A question about putting MTN bike derailleur and cassette on road bike [lyrrad] [ In reply to ]
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Okay so my Shimano 105 10 speed rear derailleur will allow for 12-30 cassette?
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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The short cage 105 derailleur can accommodate a 30T and if you have the med/long cage you can go bigger.

I'm currently running an 11-32 (http://www.wiggle.co.uk/...cassette-11-3211-34/) with a 105 10 spd rear mech. With a mid-compact chain setup you need the terrain to start getting extreme before you need to go bigger.
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Re: A question about putting MTN bike derailleur and cassette on road bike [scott8888] [ In reply to ]
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Thanks. I will still need to purchase a compact crank. I appreciate all the ST assistance. I need to determine which is the most cost effective way of doing this
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Re: A question about putting MTN bike derailleur and cassette on road bike [ginofairplay] [ In reply to ]
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No, you won't have to buy a new compact crank. If you look for a medium or long cage derailleur (http://www.wiggle.co.uk/...-rear-derailleur-gs/) you can keep your current standard crankset and go as big as 36 in the rear.

Oui, mais pas de femme toute de suite (yes, but I am not ready for a woman straight away) -Stephen Roche's reply when asked whether he was okay after collapsing at the finish in the La Plagne stage of the 1987 Tour
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Re: A question about putting MTN bike derailleur and cassette on road bike [Vincible] [ In reply to ]
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Running a 32,34 or 36 in the back will give you large jumps in the gears.
If you are needing that low of a gear to get up the hills then coasting is faster going down than pedaling, spin it up and roll.
You don't need that top gear.
At 105 level, cranks are cheap, especially secondhand.

You will need a much longer chain if you wish to run a long cage derailleur as well as a larger tooth cluster.
You will need to watch the total capacity of the derailleurs.
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Re: A question about putting MTN bike derailleur and cassette on road bike [lyrrad] [ In reply to ]
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Agree. 30T rear on current setup, compact cheap crank, and done. 34-30 is pretty low. I can see lower, but I'd try it first.
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