STI's with MTB mech for cyclocross conversion

The secret rider

Hi I have an old Carerra subway I am looking to convert to a drop bar cyclocross type bike to allow commuting and single track rides etc.

I've already gone 1 x on the rear but am now looking to change to drop bars.

I'm after some help in finding out which STi's would work with the fitted rear mech. SRAM X4 it's 7 speed.

I ideally don't want to change much if I can help it but as shimano STi's are more available second hand am I best finding a 7 speed shimano MTB mech and using shimano STi's ?

Doesn't need to be anything special just that it works.

Any help appreciated on the best way to go about this.

Pictures for reference.

Alex99

The secret rider wrote:

Hi I have an old Carerra subway I am looking to convert to a drop bar cyclocross type bike to allow commuting and single track rides etc.

I've already gone 1 x on the rear but am now looking to change to drop bars.

I'm after some help in finding out which STi's would work with the fitted rear mech. SRAM X4 it's 7 speed.

I ideally don't want to change much if I can help it but as shimano STi's are more available second hand am I best finding a 7 speed shimano MTB mech and using shimano STi's ?

Any help appreciated on the best way to go about this.

Pictures for reference.

Shimano MTB rear mech, 7-9 speed are all compatible AFAIK - ie they have the same pull ratio. If you get a 9 speed road shimano sti, you'll need a shimano rear mech, and SRAM or shimano 9s cassette. Can't help you with mixing SRAM rear mech and shimano STI lever. Do some googling! Not sure you'll keep your 7s rear with road STI shifter... but would you want to with 1x7?

trek_dan

SRAM MTB and road stuff has the same pull ratio. But think you'll be really hard pushed to find SRAM 7 speed road shifters, in fact not even sure they actually exist. I think 9 speed may be the minimum.
Why not use Tektro singlespeed levers and a bar end touring shifter if you want to make things easy and inexpensive?

Matthewfalle

Why not chuck me some pennies for 7 speed Sora rear mech and shifters that work perfectly but are sitting in the big box of unused bits - I can then reinvest that money in a Principia frame that I don't really need but really want.

Brand new cassette and cables are also available if needed.

Alex99

I'm sure you would pick up a 9s right hand side STI lever dirt cheap on ebay or even new. I'd convert to 1x9 as you're going to have to get at least one new shifter. Second hand shimano rear mech will be very cheap, new cassette, also cheap.

The secret rider

Thanks for all the replies so far and so fast it really is much appreciated.

I know 1 x 7 is less than ideal but this bike cost me nothing and i had the chainring laying around so, so far the conversion / transformation to a cc bike has been cheap which is exactly whats needed. I dont really have much money to spend on it and only want the bike to commute on and use as a tool for training when the weather is too bad for the road bike as it stands the bike weights around 12.3kg so its not exactly light as it is !

My understanding is that the wheels need to stay at 7 speed so that is why i am sticking with 7 speed as i cant afford new wheels nor do i think the use warrants it - although i don't doubt it would be nice to have more gears.

I was asking about using the original rear mech to avoid buying a new one but perhaps as mentioned above i could get one used with some shifters and fit that.

I know you can pick up cx bikes for £300/£400 used but sadly i dont have that just now so was planning on so second hard bars and stem, some cheap cx tyres, and sort the shifting issue out then getting out there?

Do people think that would work.

Ill drop you a PM about the Sora now although not sure its compatible with the range of this cassette ?

Happy to take any suggestions - i know it wont be ideal but if we can make it work it'd be cool

Alex99

The secret rider wrote:

Thanks for all the replies so far and so fast it really is much appreciated.

I know 1 x 7 is less than ideal but this bike cost me nothing and i had the chainring laying around so, so far the conversion / transformation to a cc bike has been cheap which is exactly whats needed. I dont really have much money to spend on it and only want the bike to commute on and use as a tool for training when the weather is too bad for the road bike as it stands the bike weights around 12.3kg so its not exactly light as it is !

My understanding is that the wheels need to stay at 7 speed so that is why i am sticking with 7 speed as i cant afford new wheels nor do i think the use warrants it - although i don't doubt it would be nice to have more gears.

I was asking about using the original rear mech to avoid buying a new one but perhaps as mentioned above i could get one used with some shifters and fit that.

I know you can pick up cx bikes for £300/£400 used but sadly i dont have that just now so was planning on so second hard bars and stem, some cheap cx tyres, and sort the shifting issue out then getting out there?

Do people think that would work.

Ill drop you a PM about the Sora now although not sure its compatible with the range of this cassette ?

Happy to take any suggestions - i know it wont be ideal but if we can make it work it'd be cool

Just wonder if you can find a way to get your existing SRAM shifter onto a drop bar? Not ideal, but you might find a usable solution. I know the bar diameter is different between flats and drops, but some creative jigging might get you somewhere.

The secret rider

This is also something to consider although the more i think about it the more i wonder if single speed is more suited to the bike for ease

Alex99

The secret rider wrote:

This is also something to consider although the more i think about it the more i wonder if single speed is more suited to the bike for ease

Depends on where you live and what the terrain is like. But if you want a multipurpose bike like you said (commuting and singletrack / cross), then I'd wonder whether single speed would work well. But, if your communte is short, flat and you're happy to potter along, single speed might be OK.

If you're thinking of single speed, then it sounds like top speed isn't your main goal. Why are you going for drop bars?

cyberknight

What about the issue of the different cable pull of road brake levers compared to mtb , i have a subway and im looking to do the same thing but unless i change the brakes to road version eg road i would not be able to use brifters .
I am considering using tektro brake levers for v brakes that will work with a mechanical disc and bar end shifters .
I would also need to change the front mech to a road version as road and MTB have different cable pull.

Obviously you wouldn't have the front mech issue.

To got whole hog to change to stis i would need..
avid bb5 road , around £26 each
8 x 3 speed shifters
road front mech

peterbob

Are you aware the frame will be considerably longer on a flat bar bike. drop frames are shorter because drop bars themselves add reach, the handles are in front of the the stem. It could end up far too stretched out. I considered this once to make a hybrid bike into an all weather racer with guard clearance and discs, but the frames too long.