DT shifter installation question

[mktng]

Picked up a new project for the winter.
Have it set up with 7800 + down tube shifters.

Everything else seems fine, shifts fine. However.... The shifter boss covers.. The most inner piece of the shifter that sits against the frame cannot be installed flush to the bike. Sorry for the LQ photo.



My question is..

Should I leave it?
Will it damage the shifter boss?
Is there something I should do to alter the frame in order to have it sit flush?

[Cicli]

I believe Those bases are available with different profiles and also available flat.
You don't want the base to contact the frame tube if possible.

[bewheels]

It is hard to tell from the photo how far out they are sitting. However it was not uncommon for this piece to not sit absolutely flush against the down tube on many bikes.

[mktng]

It's... More of an eyesore. I'll seek out the flat base plates. The shifters work fine. If anyone has any kicking around. Let me know.

I'll take a better picture after work. With actual light.

[Cicli]

To be clear about my reply. The only issue I have ever seen was a cannondale with a large diameter down tube. The guy was using a shifter base with a small diameter and the points of the shifter base was rubbing the finish off the downtube where they touched. Beyond that is was just looks.

[ultraman6970]

1st time I see that problem, wonder if the base plates actually belong to the levers. Wonder if you are missing a washer or something tho.

Try to find a scanned installation manual, those have a diagram of all the parts and washers.

[mktng]

Everything checks out. Pieces wise that is. I'll take a better picture tonight of everything. :)

[ultraman6970]

I had that problem before, trying to remember what it was... Hmm... :/

[Louis]

I've researched this to death and am 99.99999% sure that Shimano makes only two types of DT shifter "base plates:" The original with a relatively small radius, designed to match what we now associate with old-style skinny steel DT's, and the flat, designed to match to any diameter DT, but mostly intended for the larger modern ones.

That leaves you with two options: 1) modify one of the curved base plates by grinding down the edges of the curved portion to match the OD of your DT, or 2) just live with the look of the flat base plate.

I chose #2, and after a very short period of time got used to it and now it looks fine to me and I don't even notice it.

I would suggest you try the flat kind and ride the bike for a few months. If after all that time the aesthetics still bother you (and this is pure an problem of looks not function) you can get the old style and modify it as required to match.

Good Luck

(I love DT shifters and use them on every bike I own that has DT bosses)

[oldpotatoe]

To be clear about my reply. The only issue I have ever seen was a cannondale with a large diameter down tube. The guy was using a shifter base with a small diameter and the points of the shifter base was rubbing the finish off the downtube where they touched. Beyond that is was just looks.

Only 2 types of base plates, concave and flat. Biggish tube and the concave one won't fit snug against the tube. made for smaller tube, steel type frames. Flat might look better but it's 'correct'.

[Cicli]

Only 2 types of base plates, concave and flat. Biggish tube and the concave one won't fit snug against the tube. made for smaller tube, steel type frames. Flat might look better but it's 'correct'.

Right on. I only ever ran into the issue once. Large tube+small radius baseplate = no good. We robbed the flat ones off some barcons, problem solved.

[oldpotatoe]

Right on. I only ever ran into the issue once. Large tube+small radius baseplate = no good. We robbed the flat ones off some barcons, problem solved.

better solution.

[Louis]

better solution.

They do have better hand-feel than Shimano, but the R side shifter is hideous. The adjustment knobby thing is annoying, and the base round part is nasty looking.

Edit: and on small diameter downtubes they completely lack the fairing effect of the base plate, which also looks better than the Campy, that doesn't even try to blend the two.

[mktng]

I'm just worried something will break.

But from my searching. Shimano part·643 4300 which is the flat cover will do the exact same thing.

If I leave it as is... I should be good right?
First time setting up a "newer" bike with dt shifters. Really brings me back to feeling like a noob.

Thanks to everyone for the help. :)!

[Cicli]

If the ends of the radio us are not hotting the frame they will work just fine. May not look the best but will work just fine.

[Louis]

I'm just worried something will break.

What exactly are your worried will break?

Some bikes with DT shifters (and either curved or flat base plates) have gazillions of miles on them.

If I were dead set on using the curved type on a fatter tubed frame I would grind down the pointy parts of the plate to make them fit better.

[mktng]

When I install the cover piece. Almost seems like I have to really force it to sit as evenly as possible. Just worried the cover itself will break. Not a huge deal. I'm sure the tension of the mounting screw will sort things out. I'll be sure to keep an eye on it though.

Thanks :) !

[Louis]

If the ends of the radio us are not hotting the frame

If that's happening, then the plate isn't sitting properly on the braze-on. Sometimes paint or other stuff, either on the cylindrical or the square part, will prevent the base from moving as far in as it should. (assuming the larger diameter DT isn't preventing it) The tolerances on it can be a bit tight.

[mktng]

Yea. Really need to take some time to sit down and check it out. Haven't had much time to wrench recently. So it's just been tossed onto the bike without any final adjustments. I'm sure if it comes down to it.... A light filing wouldn't hurt to bad.

[oldpotatoe]

They do have better hand-feel than Shimano, but the R side shifter is hideous. The adjustment knobby thing is annoying, and the base round part is nasty looking.

Edit: and on small diameter downtubes they completely lack the fairing effect of the base plate, which also looks better than the Campy, that doesn't even try to blend the two.

BUT rebuildable and convertible 8/9/10s(3 spring) with LH ERGO springs in the RH lever. BTW-if anybody has srpam barends, they use the same shape ERGO springs..

[SPOKE]

I remember many builds that I have done that required me to sand/file the square of the shifter boss to remove paint overspray in order for the base plate to fit snuggly against the frame.