Lower gear for a compact?

[Tim O]

Hi to all. Just returned to cycling after many years' lay off. Used to race (road, track mountain). I'm not familiar with the latest gear. Bought a Specialized Secteur (which I love - very comfortable for older bones). Yes, I know, I should have gone for the triple but I thought I'd try the compact and I'm stuck with it now!

The set-up is Tiagra 10 speed. The cassette is 12 - 30. The Isle of Wight is lumpy. I'm unfit. I like to spin. The question: Is it possible to put a mountain bike cassette on? I've seen one in my LBS which has a range of 11 - 36. I'm not going to race, so don't need close ratios. Apart from changing the cassette, is there anything else that would need to be changed (possibly chain length etc)? Many thanks if anyone has the answer!

 

[PpPete]

Unlikely to be able to use a 11-36 cassette
The 12-30 is probably the maximum rated "by the book" but you should be able to use a 11-32 without too much diffculty if your chain length is right.
Have a look at the front end too. If it's a 50/36 you can change the inner ring to a 34.

 

[Nearly there]

Just using the gears right makes a massive difference i'd work on ya fitness so what If you have to push your bike uphill sometimes

 

[Tim O]

Thank you PpPete. That's what I thought.
And your post, Nearly There, makes a lot of sense. It's freed me from my embarrassment at the thought of pushing it up a hill...

 

[TheDoctor]

It's not being a wuss to get off and walk.
It's cross-training. Fact

If you do decide to go for a larger cassette, you may need an MTB rear mech. Just don't get a 10 speed Dynasys one, as the cable pull is different. Get as good a 9 speed one as you can, and that should work fine.

 

[wheres_my_beard]

Dump all the gears, and go singlespeed, that'll get you fit. It will also make you more attractive to everyone around you too.

I have a compact, but prefer staying in the big ring on undulating hills, which is easier than with a triple in terms of chain line, but I'm not much of a spinner. But then I live in Norfolk, so you can ignore my advice if you like.

 

[Tim O]

Just in case anyone is interested for the future, I've got an update. Went into my LBS to get something and told the owner about my thoughts on lower gearing. He said to come in the next day and he would fit an 11 - 36 MTB Shimano cassette. If it worked, I could buy it. If it didn't, no charge to me. He said he'd done it for a customer who wanted to tour the Alps and it had worked. I reckon that's damn good service. The following day, I went back, changed the standard cassette and took it for a test drive. Worked perfectly. Now done a couple of hundred miles and it continues to work well: no hesitation in going up to the lowest cog. So, if anyone needs a lower gear on a (Tiagra) compact as equipped on the Secteur - it is worth putting on an MTB cassette. It'll certainly aid touring. Hope that helps.

 

[youngoldbloke]

Just in case anyone is interested for the future, I've got an update. Went into my LBS to get something and told the owner about my thoughts on lower gearing. He said to come in the next day and he would fit an 11 - 36 MTB Shimano cassette. If it worked, I could buy it. If it didn't, no charge to me. He said he'd done it for a customer who wanted to tour the Alps and it had worked. I reckon that's damn good service. The following day, I went back, changed the standard cassette and took it for a test drive. Worked perfectly. Now done a couple of hundred miles and it continues to work well: no hesitation in going up to the lowest cog. So, if anyone needs a lower gear on a (Tiagra) compact as equipped on the Secteur - it is worth putting on an MTB cassette. It'll certainly aid touring. Hope that helps.

That is useful information.

 

[TheDoctor]

Wow!! I'm surprised that worked, but well done for updating us.
And well played on the LBS for trying it.
It gives me hope that a 12-30 cassette might work on my Sora compact chainset / 105 everything else lashup.