Murray Missile 

I finally pulled the 1990 DiamondBack Centurion Interval frameset down out of the garage rafters and started selecting parts from my "stash" for it. What I have right now are a DT Swiss 700c wheelset with 11 speed cassette hub, SRAM PG950 11-26t 9 speed cassette, a vintage CODA 52-42-32 road triple crankset (probably 3 X 7 or 8) and a set of Microshift/SunRace 3 X 9 brifters. I'll probably pick up the matching R9 front and rear derailleurs as I don't have any 9 speed that aren't already committed to other projects. Anyone see any potential problems with this combination?

nesteel 

3x9 is one of my favorite gearing setups. You're crankset will likely run fine with a 9speed chain. The vintage triples I've run with a 9speed rear have never proven to be an issue.

joejack951

As long as you use the matching 9 speed front derailleur and chain you should be fine. I’ve wasted way too much time in the past with sub-optimal front derailleur/chain combos. Not worth it, trust me

Murray Missile 

Thanks for the input, that makes me feel better. I have a '97 TREK 820 and a newer Scott Sportster I converted to 3 X 9 Deore XT with index shifting but I used all Shimano Deore on both, the TREK uses an older 3 X 8 XT crankset but I wasn't sure how the mix from different sources might work. I have a 3 X 8 GT MTB with drop bars with Microshift brifters, FSA crankset and 105 derailleurs and it all works nicely but it seems as the speed count goes up so do the compatibility issues.

ThermionicScott 

I would make sure you have an RD with adequate capacity (35T), or failing that, size your chain by big-big+1", then you should be good.

masi61

I run a 3 x 9 on my main road bike and like it a lot. I agree that you do need to find a triple front derailleur that will work with your chainrings well. Not sure if Microshift come with trim clicks for the front or not.

For Shimano Triple road front derailleurs, you really need to follow the set-up directions. It isn’t so simple to set up new cable and housing by shifting into the granny ring then pullinG the slack out of the cable while the shifter is clicked all the way down. You need the set-up block or something like a 5mm Allen wrench to unload the front derailleur spring part way toward the middle chainring when you go to snug up the cable the first time. You then use your adjuster barrel to dial in the cage clearance of your choice.

Murray Missile 

The R9 derailleurs came today and I have them mocked up on the frame, they look good against the black frame and wheels. I'm running a short cage on the rear, I've trained myself not to cross chain even on my bikes that can handle it plus the small chain ring will rarely get used except on the rare occasion I might need a bailout gear.

I put my Tektro R539 calipers on to see how they'd fit and they have too much reach, I can't get the pads high enough to fully contact the braking surfaces and there's so much arm below the pads they look ridiculous. I found a black set of R540's without logos on Ebay for a decent price, they're recessed nut takeoffs from a month old TREK and the DB takes recessed nut calipers. I'll save the 539's for something else. This is shaping up to be a pretty nice bike and to think, it's only been 4 years in the making LOL.