ViperSnake

Hello,

After reading shimano front mech manual I noticed that my SCOTT ADDICT does not come with the backup plate or the support bolt adjusted.

Its just mine or other bikes come like this?

The backup plate, so the support bolt does not damage the frame:

fietsbob

my guess its just a bumper to not have the FD return spring hit the frame tube ,

I've never seen or needed one before, in like 50 years. not a Scott brand bike owner, ever.

Number400

I highly doubt mine has one since it has been repainted but I will look tonight. What year?

ViperSnake

From what i have learned this system is parte of the design of the 22 speed shimano groupsets( dura ace 9000, ultegra 6800 and 105 5800) and it as been first implemented in DI2. Its only presente in braze on.
Its a kind of a secund support point to the frame and a way to better align the FD.

My bike is a 2015 one

oldbobcat

The backup plate is part of the derailleur package, not the frame.

Some frames are stiff enough down there that you could probably get by without it. On most others, it certainly makes the shifting crisper. An then there are frames that are so thin-walled down there they look like the derailleur could pull the tab right out. Don't take chances.

If you lack one, I'm sure your local Shimano dealer will have one or be able to order one.

ViperSnake

I can order one even online. My LBS told me that even with the backup plate he doesn't recommend using the support bolt because it could damage the carbon frame.
I asked SCOTT but still with no response.

From what i have searched with the backup plate installed there is no problem of damaging the frame.
I'm just trying to be sure of that...

fietsbob

Chain of communication : dealer asks the company , you talk to the dealer ..

How about... bend a dime to match curved tube, double stick tape it on there. ?

Andrew R Stewart 

My understanding is that this plate/pressure screw is to prevent twisting of the der during the shifting. As Shimano chases the no technique shift it becomes more and more needed to brace the der from the increasing forces that it places on the chain and ring. Given the flexible skins that modern carbon frames have and their preferred us of the lacking "braze on" clamps that this support device is needed isn't too far a stretch. But it is beyond some of our local shops to install...

It should not be hard to fab a suitable replacement. Not sure I'd use a dime, but not much more time or expense would be needed. Andy.

Jamminatrix

On some frames the support bolt actually contacts the braze-on plate, making the stick-on back plate unnecessary. I'm not sure if that's the case with the Addict, but it wouldn't surprise me. The support bolt should definitely be used, however.

ViperSnake

In the addict the bolt does not contact the braze-on plate.
I have contacted shimano and they say that the support bolt should be adjusted to prevent twisting during shifting.

I'm waiting for a response from SCOTT to see if they have some reserves on using the bolt because of frame damage even with the support bolt.

WizardOfBoz

FWIW, my 2014 Trek Domane Series Six bike has the same omission. I suspect that Trek and Scott will say "We make the braze-on fixture so strong you don't need the backup plate", and so this is a labor-saving ruse.

Bit if Shimano recommends this, but the frame manufacturer doesn't, where does that leave the user?

I believe that the backup plate is to ensure a stiffer FD mount, with better shifting and more durable adjustments. But if it will crack the seat tube...

Be interested in hearing what Scott says. I intend to contact Trek tomorrow. I'm replacing the 172.5 53/39 with a 175 52/36 tomorrow, so adding the plate (which my LBS guy gave me) should be easy at that time.

BTW, there are two styles of that plate: a flat and a curved as shown in the OP's photo. You choose which one fits your bike best.

ViperSnake

That is just what i am trying to understand. If frame manufacturers actually cared to test if that was any danger of damaging the frame, or they simply didn't pass the instructions to the assembly line and this new feature is ignored.
Has i also suspected this is not a SCOTT only issue, other frame manufacturers don't install the plate/bolt by default.
And because this is a new feature people don't even now its missing.

When i ear any news from SCOTT i will post the answers, and i am also curious to ear TREK response.

WizardOfBoz

I don't know how other folk's minds work, but when I see a set (or grub, as the Brits call it) screw that leads to nowhere, I wonder...

I didn't get a chance to ping Trek today. Perhaps tomorrow. I'll report back when I get contact.

oldbobcat

Scott didn't, others don't, they apparently don't see it as their responsibility. It would be nice if the entire bicycling community conformed to your desires, but it often doesn't. It doesn't conform to mine, either, but nobody is going to change the layups of their frames mid-season because I was too busy or lazy or indignant to read Shimano's instructions on front derailleur installation.

If you bought your Shimano front derailleur in its Shimano packaging from an authorized Shimano dealer, it included the backing plate and instructions for installing it. What's the problem?

Eventually, we may see frames whose front derailleur tabs and tab-seat tube interfaces are stiff and durable enough to withstand the torque of 11-speed mechanical and Di2 front derailleurs. Until then, Shimano will provide backing plates.

ViperSnake

The point is that the bike is equipped from factory with a 105 5800 setup, I'm not upgrading the derailleur.
So is my desire when I buy 2000$ that its correctly build and assembled according to the recommendations of all the parts manufacturers.

I'm am not worried about having to install a backup plate, i can order one and install it.
What i what is to understand why the bolt/plate was not installed in the first place by SCOTT, since its recommend by shimano for that derailleur, so i don't have a problem in the future if i have to activate the warranty.

Andrew R Stewart 

All the Treks that we assemble with 9000, 6800 or 5800 ft ders that also use the braze on mount (which is all of them) come to us with out the backing/pressure plate installed. We, the shop, are required to install this tiny bit in the right place. We have found it easiest to first do a initial der adjustment then run the screw in and just touch the frame enough to leave a slight mark. Then remove the der and place the plate over the mark. Reinstall the der, position and run the screw against the plate before doing the final adjustment.

A lot of extra time and care for a bike build. It's not surprising that we've seen a number of bikes sold by our competition w/o this plate in place (and the screw untouched). One more "cost" of the current Shimano designs that the common rider doesn't have a clue about. Andy.

WizardOfBoz

Andy,

As a Trek owner, thanks very much for this information. As former bike shop mechanic, and as an engineer, I appreciate the clarity (and sentiment) of your note. I got my Trek (a Series Six custom build, pretty much a 6.9c) second hand, but from someone who had got the bike "factory direct" (a team athlete) and I think that the fine setup work needed was not done.

As an engineer, I agree with your point that most riders have no clue about the finer points of some designs. I think the Shimano design works well when an experienced guy with some talent (I suspect you fall in that category) sets it up right. But the designs, while high-performance, do seem to be a bit more complex than elegant in design. The Shimano instructions are pretty vague, too. For example, the "converter" on the DA and Ultegra FD. I understand what it's for, but the FD instructions are not real clear IMHO. Grrrr. Sometimes engineers do not take the time to think about how the guy in the field will understand and adjust stuff.

I'm going to install the plate on my 6.9c. I guess its lucky(?) that I'm planning on switching from 172.5mm/53/39 to 175/52/36. So I'll have to adjust the FD anyway.

Thanks again for your helpful insight.

ViperSnake

Tanks for the info Andy.

Scott responded and said that the support plate should have come with the bike box with the manual and other, I suspect it didn't.
They say that SCOTT frame come with a aluminium insert on the seat tube in the area where the bolt touches the frame.
The plate is sometimes needed to better support the bolt.

The frame is reinforced but i still will get a backup plate and install it before adjusting the screw.

Thanks for the help guys.

WizardOfBoz

I rode over to Garrison's Bikes in Centreville, DE today. My shifting wasn't very good, and Rob took a look at it. He was frustrated by the fact that there were so many little things not done right (like the derailleur hanger not being straight, and not having the screws that fix the derailleur hanger very tight). I was a drop in, and I appreciated him making time for me. Even with limited time, what he was able to do (which resulted in signficantly better shifting) was impressive. Thanks Rob!

This adds to my suspicion that the bike never got a full work-over and set-up initially.

Anyway, Rob mentioned a issue you will face with the backing plate. The set, or grub-screw that comes with the bike may not be long enough to hit the plate. So you need to get a longer 3mm screw (like at the hardward store) and cut it off. The idea is that you set up the FD physically (as in the Dealer's Instruction, available on-line) first. Then you set up the FD. I'm realizing that bikes aren't the easily understood machines they were in my youth. Appreciate Rob's expertise.

One last thing: to do the FD install properly, you need a tool that measures the angle of the cable coming into the FD, and the FD's lever arm. There are two different ways to set the cable-gripping-screw assembly. The tool is the TL-FD6800 (which works for Ultegra and DA). You can also get the TL-FD9000 (which only works for DA 9000).

oldbobcat

Aha, thanks for clarifying, Snake.

But Scott did nothing wrong; the omission was by the shop who sold you the bike, specifically, the ******bag builder who didn't educate himself on installation and tuning of Shimano 11-speed derailleurs, and the service manager who allowed his mistake to get to the sales floor.

I've been assembling Di2 and 11-speed bikes from Trek, Scott, and Raleigh for a couple years now, and not one ever came out of the box with the backing plate already installed. Customarily, the derailleur is attached to the mounting tab, never at the correct height or angle, with the cable correctly routed past the converter pin and loosely fastened at the pinch bolt. It's the shop builder's job to unfasten the cable, re-position the derailleur, determine which backing plate to use and install it, tighten the grub screw to correct the angle, correct the position of the converter pin, re-fasten the cable, and finish tuning the derailleur. This is more complicated than your typical 5500, 5600, or 5700 setup.

Andrew R Stewart 

New products create new industry standards of assembly. Some shops are slow to catch up (if they ever do). Andy

Wheever

This is topical, because I just discovered my Domane 4.5 is missing that backing plate, too. When the shop put the new (larger) bars on my bike, they seem to have forgotten to adjust the FD. So I discovered the missing part by doing the factory setup. I don't know if it's even possible to get set up the FD so that there's no clattering on either trim without the set screw.

Anyway, I was able to get the plate from my LBS, and will try the setup again tonight with it.