Freehub weirdness
I think I've fixed this but am unsure as a) I've not ridden it again yet and b) I'm not sure what was a symptom, what was a cause and what was a result.
The basics: Frame is a Scott Foil, groupset is ultegra di2 and the wheel is a sram s60. Wheel is used but decent, frame and groupset have about 600 miles on them.
Went to pull away from some traffic lights and instantly had some chainsuck. Felt it happen so had already backed off and the chain fell back into place. Got clear of the lights and en stopped to have a look. No sign of chainsuck damage on the stay or the chainset, that's good. Weird but hey ho so I carried on.
A bit of looking at it when I rode on and I noticed that if I free wheeled the chain would sag as the freehub would not freewheel straight away and would continue to turn with the wheel for a moment. Pedalling and all is fine. I stopped again to have another look.
Yes, freewheel is really stiff, pedal backwards and it sticks enough that the chain will sag then jump off the sprocket. Push the bike along and the cranks will turn like a fixie. Quick check and the QR is on pretty loose. Annoyed with myself for this as it's after I had the wheels off briefly and I mustn't have put it back on properly tight which is something I'm usually really careful with. It was on though, if only light and the wheel was in the dropouts. However, I vaguely remember at the point of chainsuck that I also felt the brake rub. Only other weird thing here is that there is a small but useful chip in the paint on the underside of the non drive side chainstay in front of the drop out. I can't be sure but I am fairly confident that's new.
I've since stripped the wheel and indeed the freewheel was really stiff. Both hub bearings are fine and of the two in the freehub one is perfect the other a touch grumbly but nothing untoward. The pawls and springs were dirty but didn't appear to be overly so. Cleaned it all up, removed, cleaned, greased and reassembled the hub and all seems fine although very little tightening seemed to be required to get the preload right and not to have the freewheel tighten itself again.
So, I'm stumped as to what has happened. Has the freehub just got stiff and I've not noticed until it's a problem or has the loose qr meant the wheel jumped (but then sat back in the drop outs) and that that has done something odd to the freehub as a result; or something else? The jumping out possibility seems unlikely to me as to jump out properly the wheel would have jammed in the frame, it's very unlikely it would have sat back in the dropouts with the qr still done up especially if it got far enough to cause the paint chip. Also the freehub would have already been sticking before I stopped for the chain to be sagged enough to get sucked when I pulled away, before this I'd done about 15 miles with some proper bursts of almighty wattage (ahem) as I was doing sitting climbing intervals.
To be safe I've ordered a new freehub, pawls and bearings but it's just really puzzling and I'm now fretting I've damaged something through my own stupidity.
The basics: Frame is a Scott Foil, groupset is ultegra di2 and the wheel is a sram s60. Wheel is used but decent, frame and groupset have about 600 miles on them.
Went to pull away from some traffic lights and instantly had some chainsuck. Felt it happen so had already backed off and the chain fell back into place. Got clear of the lights and en stopped to have a look. No sign of chainsuck damage on the stay or the chainset, that's good. Weird but hey ho so I carried on.
A bit of looking at it when I rode on and I noticed that if I free wheeled the chain would sag as the freehub would not freewheel straight away and would continue to turn with the wheel for a moment. Pedalling and all is fine. I stopped again to have another look.
Yes, freewheel is really stiff, pedal backwards and it sticks enough that the chain will sag then jump off the sprocket. Push the bike along and the cranks will turn like a fixie. Quick check and the QR is on pretty loose. Annoyed with myself for this as it's after I had the wheels off briefly and I mustn't have put it back on properly tight which is something I'm usually really careful with. It was on though, if only light and the wheel was in the dropouts. However, I vaguely remember at the point of chainsuck that I also felt the brake rub. Only other weird thing here is that there is a small but useful chip in the paint on the underside of the non drive side chainstay in front of the drop out. I can't be sure but I am fairly confident that's new.
I've since stripped the wheel and indeed the freewheel was really stiff. Both hub bearings are fine and of the two in the freehub one is perfect the other a touch grumbly but nothing untoward. The pawls and springs were dirty but didn't appear to be overly so. Cleaned it all up, removed, cleaned, greased and reassembled the hub and all seems fine although very little tightening seemed to be required to get the preload right and not to have the freewheel tighten itself again.
So, I'm stumped as to what has happened. Has the freehub just got stiff and I've not noticed until it's a problem or has the loose qr meant the wheel jumped (but then sat back in the drop outs) and that that has done something odd to the freehub as a result; or something else? The jumping out possibility seems unlikely to me as to jump out properly the wheel would have jammed in the frame, it's very unlikely it would have sat back in the dropouts with the qr still done up especially if it got far enough to cause the paint chip. Also the freehub would have already been sticking before I stopped for the chain to be sagged enough to get sucked when I pulled away, before this I'd done about 15 miles with some proper bursts of almighty wattage (ahem) as I was doing sitting climbing intervals.
To be safe I've ordered a new freehub, pawls and bearings but it's just really puzzling and I'm now fretting I've damaged something through my own stupidity.
0
