Ultegra 6800 FD vs. 28c tires

[phjosephson]

I have a DeSalvo steel frame with plenty of room in the back for 28s. However, my Ultegra 6800 front derailleur arm swings surprisingly close to the tire (shown are Schwalbe One 25s). I'm worried it won't accommodate a 28 without rub.

Does anyone else have this problem? Am I missing some obvious workaround or mounting trick to free up more space?

http://i.imgur.com/DueP29Hl.jpg
http://i.imgur.com/tz5JDlHl.jpg

[Cicli]

The Parlee band is a bunch thinner. Dont know if it will be enough but it will gain you some.

[phjosephson]

I though about a band change. But with a thinner band, wouldn't the mechanism have to actuate farther (to get the cage to the same spot over the chainring), bringing the arm to roughly the same spot as before?

[Cicli]

Probably. Hmmmmmm.

[thirdgenbird]

Seems to be a common problem with the longer arm. I read a review on a kona honkey tonk that had a similar issue. The frame and brakes cleared a 32 but a 6800 rd hit on anything bigger than a 28.

A thinner clamp won't address the issue. It's a combination of fat tires, short stays and the long fd arm. Kona lengthened their stays last year so it may no longer be an issue on that model.

[phjosephson]

The frame geo on this bike is pretty standard 54cm. This seems like a really silly design oversight on Shimano's part, especially considering how otherwise well thought out the 6800 group is.

Lengthening the stays will be difficult...

[eddief]

makes me wonder if an actual clamp on derailleur would allow for more clearance, but maybe the spacing is the same with either approach?

[ty7180]

I am having the same issue. Started with a braze on fd and shimano clamp. Also tried a clamp on fd that maybe helped a mm but not enough.

[ty7180]

Forgot to mention that my issue is the tire rubbing the cable when I am in the big ring. It is not constant, just when I torque the crank pretty hard.

[phjosephson]

Rubbing the cable as it comes up from under the BB shell? Interesting.

[thirdgenbird]

I hadn't realized how much more vertical campagnolo's long arm front derailleur is when placed on the large ring:

http://cdn.mos.bikeradar.imdserve.com/images/news/2014/12/01/1417458469954-9wm8kk1xk1u4-960-540.jpg

In the small ring, it points out slightly.

[guido]

The CX70 FD subs in easily to the 6800 world and works great with big tires and small chainrings...

[Cicli]

I hadn't realized how much more vertical campagnolo's long arm front derailleur is when placed on the large ring:



In the small ring, it points out slightly.

The answer is simple then. Switch to Campagnolo.

[oldpotatoe]

The CX70 FD subs in easily to the 6800 world and works great with big tires and small chainrings...

Have you actually done this? I haven't but I don't think the CX-70 is compatible with 5800/6800/9000 shifter. Yes for 10s shifter tho.

[guido]

Have you actually done this? I haven't but I don't think the CX-70 is compatible with 5800/6800/9000 shifter. Yes for 10s shifter tho.

Yes I have. It works fine with my 6800 shifter.

[oldpotatoe]

Yes I have. It works fine with my 6800 shifter.

good to know..I hear it works great with sr(p)am shifters too..

[thirdgenbird]

What size chainring will the cx70 work with?

[guido]

What size chainring will the cx70 work with?
I use it with 46-30 with great results...

[phjosephson]

I have standard chainrings, so not sure that would work.

Do the 105 or DA derailleurs have the same length arm? Or is that unique to Ultegra?

[sandyrs]

I have standard chainrings, so not sure that would work.

Do the 105 or DA derailleurs have the same length arm? Or is that unique to Ultegra?

105 and DA are the same geometry. You could try a clamp that, rather than being thinner, puts the derailleur farther forward, toward the front wheel. I had this problem with 5800 and 25's, and a new clamp (campagnolo) solved it.

[thirdgenbird]

I have standard chainrings, so not sure that would work.

Do the 105 or DA derailleurs have the same length arm? Or is that unique to Ultegra?

Standard rings would probably be a stretch.


5800 105 and 9000 dura ace use the same arm. If the cx70 works with both old and new front shifters, it may be worth trying a 6700 fd. You might loose the light feel, but it's worth a shot if you can borrow one.

A new clamp that moves the derailleur forward isnt a bad idea.

[Deucer01]

I've used SRAM Red 10 speed front derailleur with my 5800 shifters with no issues.

[phjosephson]

If the Campy mount sits just a few mm farther forward, that would be the best (simplest/cheapest) fix. I'll have to try it. Is there just one standard Campy hanger or several?

[Ken Robb]

I guess it's too late to lengthen the chainstays. :D

[oldpotatoe]

If the Campy mount sits just a few mm farther forward, that would be the best (simplest/cheapest) fix. I'll have to try it. Is there just one standard Campy hanger or several?

Silver and black, 31.8 and 34.9.

[p nut]

Bumping this thread to see if the OP tried a Campag clamp. I'm having the same issues with a 5800 front derailer. I'm hoping the Campag clamp would solve the issue.

[weisan]

You may not like to hear this, but I have done this in a few occasions. :eek:

https://s-media-cache-ak0.pinimg.com/originals/63/89/8a/63898a873bd9cb42893d9374c7855187.jpg

It's a battle of wills!

:D

[benb]

If that was my custom frame and I specified clearance for 28s and Shimano I'd be mighty annoyed by this.

[zennmotion]

If that was my custom frame and I specified clearance for 28s and Shimano I'd be mighty annoyed by this.

I was minor annoyed to discover this also, 28c was fine but 32 wouldn't work, with frame clearance otherwise fine for 35c or more. I'm using the CX70 FD and switch back and forth between 32X48 and 34 X50 chainrings with no problem. The CX70 FD setup is more finicky compared with a 6800, but the trick is to have a little tension on the cable while the FD over the small ring- if you have one, an old school 4th hand cable pulling tool makes this easy. Fidgety (it took several rides to get it right) but once set it's set. For larger 52/53t rings, I don't see why an older 9sp or 10sp Shimano FD wouldn't similarly work- the CX70 is designed for 10sp. I think you lose a little of the crisp front shifting that's a feature of Shimano/11, but I can hardly tell the difference compared to my other road bike with 6800 FD, just an occasional need to trim, but it works fine, at least with the still fairly new (Shimano OEM) cables I'm using. Like I said, more finicky setup, but have patience, there is a sweet spot for adjustment and once you find it, the CX70 works great.

BTW, I think the newest version of the mechanical DA/11sp (9100?) FD uses a different arm design, I don't know if these are easily available yet in the usual places.

[El Chaba]

If that was my custom frame and I specified clearance for 28s and Shimano I'd be mighty annoyed by this.

This^^ No excuse....

[zennmotion]

This^^ No excuse....

This is on Shimano, not the builder IMO- the only thing that could be done to the frame would be to spec longer chainstays, and this would be a major design change for a minor problem. I think Shimano realizes the issue as they've redesigned the 9100 FD arm, hope it trickles down to Ultegra and 105 soon. In the meantime there are some fairly painless solutions with alternative FDs. It does seem like Shimano wasn't designing outside a fairly limited box of road bikes with skinny tires. I'll forgive though, at least there have been no incidents where components have spontaneously caught fire on an airplane. To my knowledge anyway...

[chiasticon]

If that was my custom frame and I specified clearance for 28s and Shimano I'd be mighty annoyed by this.well it could be an older frame he purchased used... and in my opinion, it's not the builder's fault Shimano did something incredibly stupid (but we'll overlook it because, you know, they're not Sram). but yeah, either DeSalvo doesn't know of this Shimano issue or he didn't account for it.

[zennmotion]

well it could be an older frame he purchased used... and in my opinion, it's not the builder's fault Shimano did something incredibly stupid (but we'll overlook it because, you know, they're not Sram). but yeah, either DeSalvo doesn't know of this Shimano issue or he didn't account for it.

And keep in mind that the OP post was more than a year ago when Shimano 11 speed was still fairly new on the market, no reason that a bespoke builder would be aware of the issue until/unless they were to have built up an entire Shimano bike with the new stuff.

[benb]

Bespoke builder is supposed to be way better than the big factories if you listen to stuff around here. :rolleyes: Any big factory bikes have this issue?

I still would love to know exactly what caused it. I've run that derailleur on several bikes that are specced for similar tires and the derailleur arm is nowhere near the tire. One of those bikes has long chain stays, one has moderate. Not sure why a bike with big tire clearance would have ultra short chain stays, or does this frame have a 72 degree seat tube or something..

That long arm on the derailleur has a purpose. It works on most bikes. It provides more leverage for the lighter feel at the lever and the way it's tilted back keeps the cable path straighter. My guess is shimano specced out frame requirements before the derailleur hit the market and you could have gotten them if you thought to ask. This is no different than the requirements for chainstays/BB/rear hub that they put out to keep their rear derailleurs working in spec.

[chiasticon]

And keep in mind that the OP post was more than a year ago when Shimano 11 speed was still fairly new on the market, no reason that a bespoke builder would be aware of the issue until/unless they were to have built up an entire Shimano bike with the new stuff.wow, I'm dumb and missed OP's date :crap:

still though, 6800 was out for a while by that point. at least a year. but yes, if the builder had never worked with it or been made aware of the issue, of course they'd overlook changing the frame.

[feFIFO]

This is a DeSalvo 10th anniversary frameset, circa 2008. Predates 6800. So not Mike's fault.

wow, I'm dumb and missed OP's date :crap:

still though, 6800 was out for a while by that point. at least a year. but yes, if the builder had never worked with it or been made aware of the issue, of course they'd overlook changing the frame.

[benb]

Ah that makes a lot more sense.

In any case another derailleur that I think will work is a 105 5700. It has the shorter arm. I ran the 105 & 6800 with the same 10-speed lever, they seem compatible, although someone who ran the 11-speed lever with the 10-speed front derailleur would be a better reference.

[zennmotion]

Bespoke builder is supposed to be way better than the big factories if you listen to stuff around here. :rolleyes: Any big factory bikes have this issue?

I still would love to know exactly what caused it. I've run that derailleur on several bikes that are specced for similar tires and the derailleur arm is nowhere near the tire. One of those bikes has long chain stays, one has moderate. Not sure why a bike with big tire clearance would have ultra short chain stays, or does this frame have a 72 degree seat tube or something..

That long arm on the derailleur has a purpose. It works on most bikes. It provides more leverage for the lighter feel at the lever and the way it's tilted back keeps the cable path straighter. My guess is shimano specced out frame requirements before the derailleur hit the market and you could have gotten them if you thought to ask. This is no different than the requirements for chainstays/BB/rear hub that they put out to keep their rear derailleurs working in spec.

I don't know how long is long and what moderate means, but mine has 73deg ST, and 42.5cm stays as a steel all rounder, but this is also pretty average for cross bikes. The 6800 arm just touched the tire (Michelin Jet at 33mm measured width is my go-to for gravel); I could move the rear wheel back a few mm's with the short horizontal dropouts, but it's too close for comfort especially if the tire picks up any mud or debris. CX70 solved the problem, shifts great, I never think about it anymore.

[Mark McM]

Seems to be a common problem with the longer arm. I read a review on a kona honkey tonk that had a similar issue. The frame and brakes cleared a 32 but a 6800 rd hit on anything bigger than a 28.

A thinner clamp won't address the issue. It's a combination of fat tires, short stays and the long fd arm. Kona lengthened their stays last year so it may no longer be an issue on that model.

How about a fatter braze-on adapter band? Not a thicker band, but one that has a larger diameter (for fatter seat tubes). If the seat tube is 28.6mm or 32mm, you can get a braze-on adapter for 32mm or 35mm. You'll also need a front derailleur clamp shim, but these are readily available.

With the fatter braze-on adapter, the whole derailleur will be pushed outboard a little bit more, so the actuator arm won't have to be pulled as far shift to the big ring, thus giving more tire clearance.

[zennmotion]

How about a fatter braze-on adapter band? Not a thicker band, but one that has a larger diameter (for fatter seat tubes). If the seat tube is 28.6mm or 32mm, you can get a braze-on adapter for 32mm or 35mm. You'll also need a front derailleur clamp shim, but these are readily available.

With the fatter braze-on adapter, the whole derailleur will be pushed outboard a little bit more, so the actuator arm won't have to be pulled as far shift to the big ring, thus giving more tire clearance.

Maybe, but the derailleur would still have to be adjusted to center over the small chainring, so moving outboard (probably the max using a shim could only be 2mm or so anyway) would still position the end of the arm in the same place as before, it wouldn't solve the problem. I still think the solution requires a different derailleur unfortunately. Luckily, my congressman also sponsors a bike team, I'll write a letter and get him on it- trade embargo with Japan until it gets resolved!

[Mark McM]

Maybe, but the derailleur would still have to be adjusted to center over the small chainring, so moving outboard (probably the max using a shim could only be 2mm or so anyway) would still position the end of the arm in the same place as before, it wouldn't solve the problem. I still think the solution requires a different derailleur unfortunately. Luckily, my congressman also sponsors a bike team, I'll write a letter and get him on it- trade embargo with Japan until it gets resolved!

I'm not sure that you are picturing it correctly.

If the larger braze-on clamp adapter moves the slotted tab outboard, then the whole derailleur is more outboard. Which in turn means that the parallelogram pivots are more outboard.

The closer the pivots are to being directly above the chainrings, the more vertical the parallelogram arms arm.

The more vertical the parallelogram arms are, the less inboard the top of the arm (where the cable clamps) is.

The less inboard the top of the arm is, the further outboard the cable run.

Even if you can only shift the derailleur body by 2mm, you'll actually shift the actuator arm by twice that - the length of the actuator arm doubles the effective offset.

[p nut]

Mark McM - If what you're saying is right, then I'll have to try that. I've got maybe 2mm of clearance now (700x32 Stampede Pass), which is just too close for me for comfort. I was hoping to run Bon Jon's and was excited when another 35c CX tire cleared the brakes, but never thought of the front derailer clearance issue.

One other thing I'll maybe try is a low profile bolt (if such thing exists that would fit). I'll head to Home Depot to see if I can find a match.

[ColonelJLloyd]

One other thing I'll maybe try is a low profile bolt (if such thing exists that would fit). I'll head to Home Depot to see if I can find a match.

Not likely to find it at HD, but a M5 x .8 pitch button head bolt should create a tiny bit more clearance. When I began wrenching on bikes it quickly became clear that I needed to stash my own M4, 5 and 6 bolts in various lengths and head styles and I'm very often happy I did.

[p nut]

Do you think a disc rotor bolt will work? I believe they're M5, but not sure of the pitch.

[ColonelJLloyd]

Do you think a disc rotor bolt will work? I believe they're M5, but not sure of the pitch.

Good thinking. Yes, that should work. Some pinch bolts use an M4, but that doesn't look like one to my eye. Not direct experience, though.

[thwart]

Switch to Campagnolo.

:banana:

Seems the engineers there user-test more thoroughly.

[John H.]

How about getting a 9100 front derailleur?
The 9100 has a shorter arm-

[Ti Designs]

FSA made a tandem front derailleur clamp that has more offset. It has "Tandem" printed on it. I've had to use this solution a couple of times.

[p nut]

Changed out the bolt to a brake rotor bolt. Gave me 3mm or so extra clearance. So about 5mm or so. Good enough for me. Unless I go to 35mm tires.