MTB to Rd STI's

[Hector]

I want to convert my handle bars from MTB (straight) to the Road bike handle bars - drops. Question is, will the cables fit onto the STI's for the road or do I have to replace the gear and break cables to fit the STI's (Sora 9 speed)?

[Flowta]

If the cables are long enough, not necessarily.

 

Only problem you could have is if the brakes are V-brakes, ie. not designed for road bike calipers.

 

[AndreZA]

no, cables need to be longer so you'll need new housing and cables. I'm not sure but I think you might need different brake cables aswell. The heads on MTB cables are different then road. But I can be wrong.

[javadude]

You will probably have to change the fron derailleur as well. I dont think an MTB FD is compatible with road STI's. 

[Johan Bornman]

Mampara is right, the cable heads on the brake cables are different. However, there is no wisdom in building over with vrot cables. Just replace them at the same time, then you don't have to work against the length constraint either.

 

Further, you will face brake travel problems. V-brakes require far more travel than calliper brakes and you will have to install travelators onto the V-brake levers to increase the travel ratio. Tandems use these and they are available.

 

The derailers will be compatible but your stem may not.

 

 

 

 

 

[Hector]

Thanks everyone for the advice. Will let you know once it is done what worked andwhat had to be changed.

[levett]

The derailers will be compatible but your stem may not.

Johan - I've certainly not tried this but (as we discussed) I've built that fab carbon frame into a 10-speed road bike with straight bars.

 

With this, you need Shimano 10-speed trigger shifters and a 'special' 10-speed triple (mine's a triple) front derailleur (FD-R773 I think) - apparently standard road front derailleurs don't work (the double chainring front derailleur is FD-R770 I think).

 

Would that indicate that the road trigger shifters are a different ratio (front derailleur)? And is that MTB ratio? or is it a 'special' ratio for the 10-speed trigger shifters?

 

Maybe it's just that the 10-speed shifters for straight bars are different and MTB trigger shifters are the same as STI's - if so, sorry for causing the confusion.

 

Cheers,

 

Dave.

[javadude]

 

 

With this' date=' you need Shimano 10-speed trigger shifters and a 'special' 10-speed triple (mine's a triple) front derailleur (FD-R773 I think) - apparently standard road front derailleurs don't work (the double chainring front derailleur is FD-R770 I think).

 

[/quote']

 

This is kind of what I was referring to. I was also keen on the road flat bar route at one stage and all the forums I read told me that regular drop STI's and flat bar STI's require totally different front derailleurs. The same was said of the Campagnolo flat bar shifters as well.

 

[Johan Bornman]

With this' date=' you need Shimano 10-speed trigger shifters and a 'special' 10-speed triple (mine's a triple) front derailleur (FD-R773 I think) - apparently standard road front derailleurs don't work (the double chainring front derailleur is FD-R770 I think).

 

Would that indicate that the road trigger shifters are a different ratio (front derailleur)? And is that MTB ratio? or is it a 'special' ratio for the 10-speed trigger shifters?

 

[/quote']

 

Thanks for pointing this out to me Dave. I think I was in Campagnolo mode when I suggested they would be compatible. At some stage I'll have a look at the reason for incompatibility. I can't even speculate why.... On Campag the left shifter and derailer are on a continuous friction system and the shifter doesnt care if you fit a triple or double chainring. It also has seamless trim. The Shimano system is more pre-determined where it goes to and what can be trimmed. Maybe this has something to do with it.

 

If it is a double-to-triple incompatiblity it may have to do with the sweep of the derailer. Perhaps the double can  be modified a bit to give it some more travel should you want to go from double to triple using the same derailer.

 

Also, "incompatible" doesn 't necessary mean it wont work. Shimano has lots of incompatible stuff which if you are prepared to compromise or put up with little quirks, actually work.

 

Next time I speak to a Shimano staffer I'll ask about this. It would be interesting to understand.

 

 

 

[levett]

Johan,

 

Next time I'm down (to get me new Carbon Cruiser checked out), I'll bring a 'spare' Road/Flat Bar derailleur for you to have a study at!

 

You may be right with the 'Compatibility' issue - apparently an Ultegra 6703 Front Derailleur is only compatible with 6700 STI's (but a 6600 Derailleur is compatible with 6700 STI's )

 

Cheers,

 

Dave.

[Hector]

Stuff it - after reading all the above, I am now scared to try this out. All I want to do is get a better riding position on my MTB for road training. I live in the Transkei and train on a Merida TFS500 because the roads are so bad, full of glass and pot holes. I put on slicks, changed the front rings to 28/38/48 a 11/21 cluster and a Polar CS600 power meter. The only thing is, one can not get down low enough with the striaght bars when wanting to do some pace work. i have got all the part now, so I will try it out any way.

[levett]

I read a review and the guy said he used his 105 Front derailleur with the 'trigger shifters' with no problem so, like Johan says, Shimano say things are incompatible but, in practice, they work fine.

[Woofie]

What about putting some tri bars onto your mtb.

 

After all, you are not mtbing anymore on it, so its not like you are scared of falling and trashing them.

 

 

 

I have been thinking of doing this.

 

 

 

I commute to work on my roadie, but because of the road condition at places I want to get off the road.

 

So I have put slicks on my mtb and it is ready to be used for that.

 

I think I will look into the tri bars thing as there is some pretty long stretches where getting lower down will definitely help big time.