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-   -   Front derailleur hanger Trek OCLV - compact (https://www.bikeforums.net/bicycle-mechanics/863843-front-derailleur-hanger-trek-oclv-compact.html)

dbg 12-22-12 08:55 AM

Front derailleur hanger Trek OCLV - compact
 
Swapped to a compact crank on my '04 5900 Superlight and realized the existing hanger doesn't allow it to drop quite enough for the smaller big ring. The hanger is removable. I can only find a vague reference to an "OCLV front hanger - compact" on a UK web site. But it says "special order only".

Does anybody know of a place to order one of these?

well biked 12-22-12 09:10 AM

Have you checked with a Trek dealer?

dbg 12-22-12 09:16 AM


Originally Posted by well biked (Post 15077594)
Have you checked with a Trek dealer?

You're right. And I'm feeling a little silly for asking before checking with Trek dealer. Moderator should feel free to remove this posting.

pmt 12-22-12 04:28 PM

Normally we just file down the slot in the hanger a bit and then it works fine.

ultraman6970 12-22-12 06:52 PM

+1, some bikes were designed before the compact times and are off a few mm, thats what a good file or a dremel work perfect for stuff like this.


Originally Posted by pmt (Post 15078582)
Normally we just file down the slot in the hanger a bit and then it works fine.


HillRider 12-22-12 07:04 PM

The radial difference between a 52T or 53T and a 50T chainring is about 4 to 6 mm and that's a lot to file off.

DieselDan 12-22-12 08:20 PM

Could you remove the hanger and use a clamp adapter?

LarDasse74 12-22-12 08:49 PM


Originally Posted by HillRider (Post 15078955)
The radial difference between a 52T or 53T and a 50T chainring is about 4 to 6 mm and that's a lot to file off.

You would only have to file that off i the derailleur was in the absolute lowest position with the larger ring installed. Most people would have to file off much less. Still a fair amount of effort compared to installing a different hanger.

HillRider 12-22-12 09:25 PM


Originally Posted by LarDasse74 (Post 15079238)
You would only have to file that off i the derailleur was in the absolute lowest position with the larger ring installed. Most people would have to file off much less. Still a fair amount of effort compared to installing a different hanger.

Yeah, I calculated the worst possible case. You would think the manufacturers would have recognized the existance of compact cranks several years ago and constructed their braze-on tabs accordingly. Maybe compacts weren't a consideration in '04 when the OP's bike was manufactured.

As to a clamp-on adapter, I expect this frame doesn't have a round enough seat tube to use one or Trek wouldn't have bothered with the tab.

jimc101 12-23-12 12:51 AM


Originally Posted by HillRider (Post 15079317)
You would think the manufacturers would have recognized the existance of compact cranks several years ago and constructed their braze-on tabs accordingly. Maybe compacts weren't a consideration in '04 when the OP's bike was manufactured.

Maybe it was more that Trek didn't consider that the customers who were going to buy a 5900 would want a compact?

Compact is current now, not sure about 2004, got my first compact back around 2008 so they were around then, but now that Shimano has 52/36 cranks coming out (thinking they will filter from Dura Ace, probably with the next gen of Ultegra) , I've got a feeling that compact maybe disappearing again; given that a manufacture can make one crank/BCD for their complete range with this vs 2 needed for compact and standard, and the ever widening ratio cassettes now available.

LarDasse74 12-23-12 12:09 PM


Originally Posted by jimc101 (Post 15079735)
...but now that Shimano has 52/36 cranks coming out (thinking they will filter from Dura Ace, probably with the next gen of Ultegra) , I've got a feeling that compact maybe disappearing again; given that a manufacture can make one crank/BCD for their complete range with this vs 2 needed for compact and standard, and the ever widening ratio cassettes now available.

I am not familiar with the strategy Shimano uses for the new DA crank, but it is unlikely the rest of the cycling world will follow. A normal compact 110mm bolt circle crank can already be used with a 52 tooth ring if you wish, and Shimano has a history of weird chainring configurations that disappear after a year or 2.

jimc101 12-23-12 01:28 PM


Originally Posted by LarDasse74 (Post 15080704)
I am not familiar with the strategy Shimano uses for the new DA crank, but it is unlikely the rest of the cycling world will follow. A normal compact 110mm bolt circle crank can already be used with a 52 tooth ring if you wish, and Shimano has a history of weird chainring configurations that disappear after a year or 2.

The change for 9000 is one BCD for the entire lineup of crank options, would expect this to filter to lower groupsets purely as it's going to cost less to make 1 SKU rather then 2.

Who is the rest of the cycling world though!, the big players are Shimano, FSA and SRAM, as I said, it's only my feeling of what will happen, but Shimano hasn't made too many mistakes recently, since Bio-pace (a product before it's time), the MTB DCL's didn't take off, but struggling to think of what else has flopped for them, suggestions...

LarDasse74 12-23-12 01:41 PM


Originally Posted by jimc101 (Post 15080873)
The change for 9000 is one BCD for the entire lineup of crank options, would expect this to filter to lower groupsets purely as it's going to cost less to make 1 SKU rather then 2.

Who is the rest of the cycling world though!, the big players are Shimano, FSA and SRAM, as I said, it's only my feeling of what will happen, but Shimano hasn't made too many mistakes recently, since Bio-pace (a product before it's time), the MTB DCL's didn't take off, but struggling to think of what else has flopped for them, suggestions...

Low-normal derailleurs (rapid rise)
Numerous chainring bolt patterns, including the last generation DA triple, mid/late nineties STX, Alivio...
SPD Road pedals
Aluminum tall-flange cassette bodies
'remote'(bar end) mtb shifters
... there are more, I am sure.


Yes all the products that were practical and successful stuck around, but the products that disappear are seldom seen even when in production. Shimano's success comes from equal parts successful innovation, and quick removal from the catalogue of unsuccessful ones.

Trakhak 12-23-12 02:16 PM


Originally Posted by LarDasse74 (Post 15080899)
Low-normal derailleurs (rapid rise)
Numerous chainring bolt patterns, including the last generation DA triple, mid/late nineties STX, Alivio...
SPD Road pedals
Aluminum tall-flange cassette bodies
'remote'(bar end) mtb shifters
... there are more, I am sure.


Yes all the products that were practical and successful stuck around, but the products that disappear are seldom seen even when in production. Shimano's success comes from equal parts successful innovation, and quick removal from the catalogue of unsuccessful ones.

Not to promote further thread derailment, but Shimano had a few duds before even before Biopace, e.g., Positron, Positron II, Direction 6, Pitch 10. Anybody remember any others?

jimc101 12-23-12 08:20 PM


Originally Posted by Trakhak (Post 15080971)
Not to promote further thread derailment

Isn't what BF is all about!

For the bar end shifters, they were a great idea, just never got past XTR, then came riser bars, and that killed them, as you don't use bar ends with risers. More a case of evolution of cycling than Shimano getting it totally wrong.

good call on the others though.

Al1943 12-23-12 10:03 PM

I used a Dremel to grind down the slot on my wife's OCLV front derailleur hanger to accommodate a 49-39-28 crankset.
The seat tube on the 5000 series OCLV's is round. My C-50 Colnago has the same type of "braze-on" FD hanger as the Treks.
I've always assumed that clamp-on FD's were not preferred on CF tubes due to potential damage.

pmt 12-25-12 01:38 PM

Really, it's only about two minutes with a round file and it's done. Don't overthink it.

Al1943 12-25-12 09:08 PM


Originally Posted by pmt (Post 15086543)
Really, it's only about two minutes with a round file and it's done. Don't overthink it.

That depends on the size of the rings to be used.


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