What do i need to convert my bike from a 7 speed to a 9 speed?

You may have problems with the spacing for the rear wheel. a 7 speed is 126 mm wide and a 9 speed is 130 mm wide. You can widen a steel frame but not an aluminum one so you are pretty much out of luck. Look for 7 speed sti shifters.

The 2300 Pro is the one with 3 tubes of fiberglass covered in carbon fiber if I remember correctly.

1) Since the rear cogset on your bike is most likely a freewheel and not a cassette you will need to either lace the appropriate hub to your existing rim (requires new spokes and of course a new hub) or get a new wheel that will accomodate a 9 speed cassette. The new wheel will be cheaper;

2) You will very likely need to replace your crank. It is likely that the chainrings are too wide to accomodate a 9 speed chain and the spider spacing (the spider is the thing that the chainrings bolt to) may be too wide causing the chain to get stuck between the chainrings;

3) If I recall the rest of the drivetrain on the bike is Suntour (but I may be wrong). If it is Suntour then you'll need new derailleurs front and rear. Even if the derailleurs are NOT Suntour you'll need a front derailleur at the very least since the 7 speed cage width is too great to allow peaceful shifting.

Doing quick math in my head, it may very well be cheaper to just buy a new bike with a Tiagra group on and swap the parts, that is if you are willing to have your existing frame spacing reset... oops... you can't have the frame reset because of the aluminum/carbon construction.

Oh no, I just typed all of this for nothing. Your frame has 120mm or 126mm spacing and 9 speed is 130mm. None of this will work unless you want to risk breaking the frame or possibly setting the bike up for sudden catastrophic failure by "squeezing" the wider wheel into the frame.

Sorry, your idea is a no-go.

The answer is not good:

You will need a new rear wheel (actually just a new hub, but then you;ll need to have a hopp laced to that hub). You then will need to buy a 9 speed cassette, new chain, 9 speed shifter, 9 speed rear derailleur and new cables to get them working.

Your frame *should* be able to handle fit the new hub, if not, you will need to lengthen the frame (not hard).

If you buy any sort of quality (even low-mid quality) components, you are looking at around $150-$200.

Cable: $10

Housing: $5

X.7 Shifter: $30

PG950 Cassette: $22

PC951 Chain: $16

X.5 Rear Derailleur: $35

Wheel: $60

This is from price point (except the wheel). I just estimated the cost of a rear wheel.

This is without shipping and without installation. Add another $50 for installation and probably $25 for shipping

**this is for Mountain bike pricing. Are you going road bike?

an 18 speed klein might have 3 jewelry on the front X 6 coggs on the decrease back wheel. To get a ten speed you will possibly want a street motorcycle crankset (which has 2 jewelry) and a 5 speed cogg set. looking on whether you have a cassette, or a freewheel; you would be able to and would not have the means to place a 5 speed cluster on it, or you would be able to could get yet another rear wheel. you will possibly want 10 speed shifters, a street motorcycle crankset, and a ten speed chain.

You will probably need to change the rear hub so that the 9sp cassette will fit. And to do that your bike shop would need to rebuild your wheel and they can tell you if you need anything else.

go to a bike shop

a lot of money and trouble

what do you expect to gain by this?

wle

a new bike