So I took my new (new to me, bought used on ST) Zipp 606’s out for a test ride last night. Ride was fantastic, everything went fine but there’s a pronounced ‘tic’ that comes from the front wheel every revolution.
Now, I’m mechanically inclined and do almost all my own wrench work on my bikes but I could not for the life of me find out where this was coming from.
The wheels have (or at least were sold to me as having) ceramic bearings and then mounted on the bike the front hub has no slop or is not loose side to side in any detectable way. The wheel spins freely and seemingly will go on forever if given a slight push and there is no sound/tic when it’s spinning with the wheel raised off the ground which confirms that there is nothing hitting breakpad or so on. If that was the case I’d expect to hear something every time the wheel spins. But it is only reproducible when the bike is being ridden.
The tire is a Vittoria tubular in good shape and I can’t find anything embedded in the rubber that would make the sound. Tire appears to be glued on well and is not loose. The wheel is mostly true but there is a small hop in it at one point, not bad, maybe 2mm but that is all I can find wrong with it.
The sound is coming from the same spot on the wheel every revolution. It’s fairly loud and a very pronounced click. Like most on ST, I do all my riding at 25-33 mph minimum so at my normal speed it sounds like I have a playing card stuffed in my spoke as I come flying down the road.
Any ideas on what could be causing this? Should I tear apart the hub and check the bearings?
either the carbon dust cover is loose (unlikely) or it’s the valve rattling against the rim. wrap the valve in rubber band so that it is flush with the rim and see if it goes away.
Any chance it might be the speedo magnet. I know that with mine will sometimes hit only when the wheel is under load so I stop and move it out a bit further. Often it won’t make the sound when I lift the wheel off the ground and give it a spin. Otherwise I have no clue.
either the carbon dust cover is loose (unlikely) or it’s the valve rattling against the rim. wrap the valve in rubber band so that it is flush with the rim and see if it goes away.
Do you mean the small carbon disc at the hub when you say dustcover? Checked them and they seemed tight.
There is a very little bit of slop between the valve and the valve hole in the rim. Not much at all but I can ever so slightly move it back and forth. Didn’t think it would be enough to make a sound every time around but then again maybe that’s it. Will try that tonight, thanks…
It might be how the tubulars are glued/taped to the rim. It seems that everytime I mount a new tubie there is a crunching sound somewhere on the wheel rotation. This noise is from the tubular getting pressed against the rim when that part rolls over the pavement, then it releases when it leaves the ground because the tape is not catching at that spot. Figure out which part of the wheel rolls on the pavement when the noise occurs then grab the tubular at that point and move it from side to side as if you are trying to take it off. If the noise occurs then there ya go. No big deal.
Can you hear the tic at low speed, say just leaning over your bars and rolling back forth over the spot it tics. Had a similar problem and it seemed it was one little spot on the tire that just wasn’t glued properly. Visually it looked like it was sealed all around. Removed the tire, applied an even layer of glue, put the tire back on and never heard from again.
Can you hear the tic at low speed, say just leaning over your bars and rolling back forth over the spot it tics. Had a similar problem and it seemed it was one little spot on the tire that just wasn’t glued properly. Visually it looked like it was sealed all around. Removed the tire, applied an even layer of glue, put the tire back on and never heard from again.
Darren
Yes, it happens even at the slowest of rolling (ie just in the driveway).
Sounds like I need to pull the tire and re-glue.
Thanks for the tips…
I had almost the same exact issue, Zipp 808 and Tangentes. Only happened when I was riding (with the extra weight on the tire), but at any speed. Ended up being the valve stem ticking on the inside of the rim. I was able to stuff a little tape around the valve and the noise went away.