Just got a Renn disc I am hoping to use at Eagleman this weekend and have a couple questions for the ST experts. I’ve taken it for a couple test rides and it seems the wheel is rubbing slightly against the brake pads. Do the brake pads need to be adjusted to a wider setting with a disc? If so what’s the rule of thumb as to how much wider they need to be set? Also, for those of you with clincher discs, do you lay down some rim tape or just thrown the tube on? Thanks in advance.
I had to adjust my rear brake slightly wider.
the clincher rim is 20.5mm wide. most training wheels are 19-20mm. we recommend 4mm clearance per side. the lighter aluminum axled hub does flex slightly more then the older steel axled hub.
we also recommend a short piece of rim tape at the air hole.
frank
Mine runs fine with the same adjustment as my training wheel. That being said, I open it up a bit for tri races because the last thing I need to do is be 0.5mph slower from the brake dragging, plus I almost never use brakes during races. For those safety-conscious, they still work fine I just have to squeeze further to get them to grab. I did this because I discovered my front brake dragging at mile 50 on a 1/2 IM recently…
On Frank’s recommendation I put a small piece of rim tape around the valve hole when i got my Renn last year. Yes, I have to open up the brakes a little, too. Just a few turns of the barrel adjuster.
Hey Frank- while we’ve got you around I have another question. Every time I switch from training wheels to the disk on my P3 the derailleur indexing is all off and I have to monkey with the barrel adjuster to get it to shift properly. Can I somehow shim the cassette to get it in the same relative position as the one on my training wheel so I don’t have to adjust the indexing? If I’ve got to turn the barrel adjuster 4-5 turns, how thick a shim would I need to add, and would a shim leave enough threads on the cassette nut to secure it?
this is very unusual. what are your training wheels? if any adjustment is needed it is more like one or two clicks.
frank
They’re the stock Spinergy X Aero X’s that came with my P3. I agree that this is unusual. When I was running the disk on my Trek OCLV I didn’t have to make any adjustment at all when switching from the Rolf Vector Pro to the disk.
jkatsoudas,
You should have put the Rolfs on your P3 instead of the Spinergys! I apologize Paul. I love mine, they were my first aero wheelset. Now they are my training wheels for my time trial bike.
This is definitely odd, as I can switch from my Mavic Open Pro/Ultegra to the Renn with absolutely no adjustment required. I would guess your Spinergys are not to spec on the cassette offset dimensions…boy that would be a HUGE surprise. (that’s sarcasm btw… 
) If you are running DA 10sp make sure you transfer over the little spacer, as that 15 or so thousandths of an inch could contribute to that sort of problem.
I actually race with the Rolf on the front and the Renn in the rear since I haven’t bought a true front race wheel yet, but for training I haven’t bothered to swap wheelsets. I do love the Rolfs compared to the Spinergys (sorry Paul) and I might eventually pick up another set of them cheap on eBay to replace the xAerox’s. in the 4 months I’ve had the P3, I’ve had a spoke come loose in the rear and a strange noise in the front. According to the LBS there’s some sort of support piece that get’s pinned to the rim before welding and it’s not uncommon for these to break loose and rattle around. It’s actually quite maddening. All the LBS could recommend was to squirt some silicone or foam or something into the spoke hole to hopefully stop it from rattling around. But I digress… Sounds like I’m stuck with adjusting the rear der between the Spinergy and the Renn.
Nope. “Just” DA 9sp on this steed for now. Good to know about the spacer, though, in case I upgrade in the future.