Front Derailleur Bracket

I had this page taken down for a copyright infringement that I can't so far find out why so I've taken any brand names off and links to shops in the hope that sorts it.

Having had some issues with the front hanger, I ordered two replacement brackets. One which turned out to be curved and not adaptable at all as the whole geometry was wrong. The second was much better

Here are the side by side pics, new one on the left existing china one on the right

Now when I ordered, I could see the base plate that bolts to the frame looked much thicker, I expected the bracket to set the derailleur too far out, but quite the opposite, it sets it closer to the frame as the slot is not as far out, so the offset is less. Fortunately, there is enough tolerance in the mech to cope. I've installed everything and now changing the front when on the largest cog at the back is 10 times smoother, all changing is better, the new bracket has a much narrower slot which leaves much more material to do the job.

The new bracket is much deeper than the china one, and it just fits in the recess in the frame. All in all a much better product. I have done another 14 mile TT and several solo rides and it's performing perfectly.

Living with a Chinarello

Hi,

Thought I'd update a bit now the weather has improved and I've been out on the bike and ridden my first TT.

First few test runs were fine, then the front derailleur started catching on the chain ring  Had to ride on the big cog till I got home and found that the front bracket had rotated slightly, enough to be a problem. So I undid and tried to tighten it more to find the hex hole in the bolt starting to round.

I backed off and ordered some more higher grade Stainless bolts. The ones installed are longer than a bottle cage bolt so I had ordered 16mm long M5's in A4 grade stainless (marine grade)

first bolt went in fine, second one got stiff as I screwed it in. After trying a few more bolts with the same problem, I thought OK a bit of resin, so used a bit of force, not much, and the whole insert started spinning. WTF! Not happy! Why two separate inserts and not one? Why can an insert spin so easily. My look 481 has a spinning insert on one bottle cage, come on RnD peeps, inserts with a non circular outer please or double inserts connected at the back, with actual metal!

So, I had to cut a groove in the insert so I could hold it and withdraw the bolt. I've cut grooves in the side and re-applied resin to stop it spinning. I tried re-threading the insert but it's aluminium and I'm scared of it just messing up, So I have cut the new bolt to same length as the old one and it's fine with a good 5mm's worth of thread gripping. I can torque it up adequately and carbon assembly grease is very useful to stop things slipping.

So one drama sorted, re-installed and got a similar thing, slight rotation but this time between setting and tightening the hanger bolt. I checked the bolts, used some carbon assembly paste behind the bracket to stop any movement but it's still doing it.

I've discovered the problem. The Bracket is made from aluminium and after the slot is cut in it for mounting the hanger, there's just not enough material left, there may be a bit of over torque on my part but the bracket is just deforming as I tighten it. I've had it in the shed and hammered it back into shape, re-installed using assembly compound to prevent slippage at lower torque and it's fine but I've also ordered a new bracket.

This one looks like it's made from steel, granted I'll need to flatten the frame side but that's no problem. If this one doesn't fit due to me having to flatten it, then there's this one too which is aluminium. Both are less than £10 so it's no big deal and have a substantial amount more material on the outside of the slot.

Other than this small teething problem, the rest of the bike is performing very well. My first TT was a hilly 14 mile, I hoped for sub 50 and got sub 43. I've only been riding 6 months so averaging 20mph was my goal and managed it. Doing the same one again this weekend with some position adjustment after seeing pics and realising that I need to make a few adjustments. This is my first venture into tri-bars too. So far so good.

Some more outside pics

Frame Measurements

People have asked about actual frame dimensions so here they are as stated by Great Keen and my measurements for a size 53cm frame

Size 530/530
L1 534.1/530 It's a tear shaped seat post so I'm measuring to it's overall centre
AR 406/406
S 582/582
E 72/72
F 43/Can't measure accurately
G 977.1/980
T 270/270
A 125/125

So it's spot on really, to measure top tube I measured the height of the top of the head from the floor and went up to the same height on the seat post so it should be right, 4mm is nothing really.