Front derailleur (lack of)

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Rob87
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Front derailleur (lack of)

Post by Rob87 »

Eyup all.
Got my first road bike atlast, a specialized allez sport however it has no front Derailleur, for what i paid thats fine.
So then, it has on the frame what apoears to be an inch of semi circle (whey a bit of pipe cut lenghways if we're honest).
Noe then i can fix my own motorbikes so this is all new to me, can i buy any derailleur and put it on or are they model specific? The front has two rings of teeth and the rear 8 (meaning s 16 speed i think!).
Also are they a ball ache to fit as i need a new cable for it aswell (no idea how to fit that either).

Many thanks people.
niknakmb
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Re: Front derailleur (lack of)

Post by niknakmb »

Any pictures ?
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Hemipode
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Re: Front derailleur (lack of)

Post by Hemipode »

You'll need a derailleur that is braze on mount not a clamp one.
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meic
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Re: Front derailleur (lack of)

Post by meic »

You need a "braze on" derailleur for a "double".

Then you need to know which make of "gear lever" you have, if it is road or MTB style and whether the cable goes under the bottom bracket or along the top tube. The guides should be on the frame, even if the cable isnt.

Then how many teeth on each of the front rings for the best fitting derailleur.

It is most likely Shimano and road with the cable underneath "bottom pull", so this would be the sort of thing
http://www.ribblecycles.co.uk/shimano-s ... #pid=34518
The braze on option. It is 9 speed and 8 speed would be better but a bit harder to find.

Not recommending this one, especially as it doesnt mention ring sizes but it gives the idea.
You should be able to get better Tiagra or 105 and possibly old 8 speed and cheaper than that.
Yma o Hyd
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gaz
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Re: Front derailleur (lack of)

Post by gaz »

Rob87 wrote:Also are they a ball ache to fit as i need a new cable for it aswell (no idea how to fit that either).

Do you know what type of shifters you have? The front mech will need to be compatible. Assuming they are Shimano STI road units fitting outer and inner cable can be fiddly but it is a DIY job so long as you have suitable cable cutters.

Fitting the mech to the braze-on is simple enough. If there is a quick link to separate the chain use it to thread the chain through the cage plates.

Generic maintenance instructions should help setting it up once it has been fitted.
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Rob87
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Re: Front derailleur (lack of)

Post by Rob87 »

Didnt expect a reaponce so quick!
I think the teeth are 32 and 58 upfront. Shall get photos on here tomorow. Excited to get out. Can i still ride it using only 8 gears??
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meic
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Re: Front derailleur (lack of)

Post by meic »

Can i still ride it using only 8 gears??

Yes or 16 if you lift the chain off by hand. While stopped and not pedaling if you wish to keep your fingers.

I doubt it is 58 that is a bit on the large side.
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eileithyia
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Re: Front derailleur (lack of)

Post by eileithyia »

meic wrote:
Can i still ride it using only 8 gears??

Yes or 16 if you lift the chain off by hand. While stopped and not pedaling if you wish to keep your fingers.

I doubt it is 58 that is a bit on the large side.


+1 for the 58t, very unlikely, I have a 56t top ring on my race bike and the jump between a 32 to a 58 would be nigh on impossible without the chain fouling up in the the gear mech.
I stand and rejoice everytime I see a woman ride by on a wheel the picture of free, untrammeled womanhood. HG Wells
ChrisF
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Re: Front derailleur (lack of)

Post by ChrisF »

eileithyia wrote:+1 for the 58t, very unlikely, I have a 56t top ring on my race bike and the jump between a 32 to a 58 would be nigh on impossible without the chain fouling up in the the gear mech.

That's possibly why there's no front mech on this bike? Someone trying to be clever, fitted wide-range rings but it never worked so they took off the mech.
Chris F, Cornwall
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andrew_s
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Re: Front derailleur (lack of)

Post by andrew_s »

The slot in the braze on would be unlikely to be long enough to allow the front mech to be positioned high enough for 58T.
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gaz
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Re: Front derailleur (lack of)

Post by gaz »

meic wrote:I doubt it is 58 that is a bit on the large side.

Every subsequent post has agreed (unsurprisingly). Can I be the first to add that the inner ring is going to be bigger than 32.

50/34 and 53/39 are fairly common set ups.
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eileithyia
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Re: Front derailleur (lack of)

Post by eileithyia »

ChrisF wrote:
eileithyia wrote:+1 for the 58t, very unlikely, I have a 56t top ring on my race bike and the jump between a 32 to a 58 would be nigh on impossible without the chain fouling up in the the gear mech.

That's possibly why there's no front mech on this bike? Someone trying to be clever, fitted wide-range rings but it never worked so they took off the mech.



Yes indeed, hadn't though of it from that angle, though why anyone would want a 58 for a bike to ride around on is beyond me. :lol:
I stand and rejoice everytime I see a woman ride by on a wheel the picture of free, untrammeled womanhood. HG Wells
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