mbt9000

im converting my boardman hybrid comp into a cyclocross bike and im unsure what shifter and derailleur combo to get, my margin is about 110 pounds, im choosing between these two sets what do you think would be better

(90 pounds for both)
B257 Shimano Tiagra 4500 ST-4500 9 X 2 Nine Speed Double Shifters STI Levers

Shimano Sora 3500 9 Speed Rear Derailleur (medium cage)

or

Campagnolo Xenon 9 speed STI Shifters and Campagnolo Xenon 9 speed rear mech (105 pounds)

which would be a better buy? both are brand new


ive got everything else for the conversion, drop bars, cables, tape etc

just stuck on this haha

mike

alcjphil

What wheels will you be using? Shimano and Campagnolo 9 speed cassette spacing differ enough that neither will work perfectly with shifters and derailleurs from the other brand. If your bike has Shimano components now, either of the Shimano groups will work well. There is little difference between the two, since current 9 speed Sora is very similar in quality to the older 9 speed Tiagra. Unless your bike currently has road style flatbar shifters you may also need a new front derailleur as well

jimc101

If you really want a cross bike, would sell the Boardman, and look at the new 13 range from Halfords, they do a CX bike with discs for £499, which looks pretty unbeatable. or for £599 a Boardman CX bike.

For the idea of converting any flat bar bike to drops, you will never end up with a bike designed to work correctly with drops, STI's are the most expensive part of the bike, and 4500's are going to be hard to find new, probably well used if 2nd hand. The Campag idea won't work well, as, as #alcjphil notes, you need a new rear wheel, as Shimano and Campag at 9 speed have no compatibility.

With the Shimano you have spec'd, why do you need the RD? if no larger cassette!

You haven't mentioned tires either have you budgeted for them, as if going off road, the hybrid ones won't work well.

alcjphil

Just reread your initial message and I realize that you were only talking about one choice for Shimano. You don't need to change the rear derailleur unless you currently have a SRAM rear derailleur. What you may have trouble with is your brakes. If your brake levers are currently the type for v-brakes, you will have to change to road style brake calipers

mbt9000

ahh i see, the mechanic said that id have to change the rear derailleur and get same shifters (campag + campag) for it to work ok, and the disc brakes arnt hydraulic so it would be a case of routing the cable and connecting, but what do you suggest, will the shimano sti shifters and rear derailleur be ok? and get fatter tyres? because the disc brakes shouldnt be an issue

and yes i have a SRAM X5 REAR AND FRONT MECH AND SRAM SHIFTERS

alcjphil

The brakes are not as simple as you seem to think. They are probably designed for V-brake type levers. You will have to replace your brake calipers for ones designed for use with your new drop bar brake levers. The pull ratio is different for road levers
So, you are going to need brifters, front and rear derailleurs, and new brake calipers

mbt9000

bugger it then, seems too much hassle, ill keep the boardman as it is and concentrate on my vintage racer that i restored (my old faithful) giving her some new bar tape and aero brakes, current ones are knackered haha, and a new rear brake, and i even may upgrade to a 6 speed freewheel i have a few laying around gotta love vintage bikes, its from the 70's and the frame is solid and not one spec of rust im lucky lol