What happens to the rear wheel skewer when I tighten the trainer clamp and see the rear stays (alu) pinch together a little?
Is it flexing? bending?
I use a steel skewer.
Changing a cassette recently and noticed that the skewer seemd to stick or rub just a little somewhere within the hub as I inserted the skewer.
I’ll give it a closer exam this eve, but there was no obvious bend in the skewer and the wheel seemed to spin fine.
c’mon, somebody…
I’ve wondered about that myself.
I’m not sure what happens to the skewer either. I always use a “junk” skewer when I use my trainer.
That being said, I’ll take a stab at explaining it. .
I would personally think that it would not be too easy to permanently bend a skewer my tightening a trainer too tight. That is especially if it was steel. Due to the axial forces are applied in solely the axial direction, I would think that the treads would give out before the skewer would bend. Plus the skewer would be somewhat protected by the shaft in which it is inserted.
…just my thoughts.
Okay so, maybe the skewer flexes when the trainer clamp is tightened, but it’s not a permanent bend.
But if I feel a rub or bit of sticking point as I insert the skewer maybe there is a slight perm bend? I need to pull it out and roll it on a flat surface or something.
Permanent or not, I’m wondering whether it’s worth worrying about the flexed skewer contacting the inner diam of the shaft/hub/axle or whatever the term is.
well I use the steel Skewer that came with my trainer. It kind of has a more domed end that fits better into the clamps on my trainer.
If you tighten just the skewer in the trainer clamp (i.e.- like you see in a bike shop when the bike isn’t attached), it will flex.
When you tighten the skewer while it’s in the rear wheel the skewer has too much support provided by the hub, the trainer flexes instead and no damage is done to either the skewer or the hub.
That being said, it is not necessary to overtighten the trainer adjustment, just keep it tight enough so that the trainer flexes a little and the wheel is held in place.
Even if it is bent, it doesnt’ really matter. There is no relative motion between the skewer and the ID of which it sits. The skewer is just there to retain everything.
Actually, the skewer doesnt really have anywhere to go. Once the wheel is clamped you are pushing against the axle, cones, hubshell, etc. as a unit. If it were deflecting, that would mean you had some VERY loose bearings/cones. Make sure that it isnt the trainer widening from the force of clamping. This happens on my Cycleops that uses a screw type clamp.
I do notice the legs of my Kurt Kinetic widening as I start tightening the knobs, it happens on even the first couple of turns once I have set the lock in place.
What I do also notice is that using my bike on the trainer makes the shifters go out of sync and when I take it off the trainer to ride they are not smooth and need tuning. Is this something normal?, do you guys also see this?