Today I almost died!
I was cruising down hill during evenign rush hour when i tried to brake/skid and my cog suddenly came loose. I managed to stop with my foot on the rear wheel and only loosing some tread on my shoe sole.
I was really suprised, bc I had just tightened the cog and lock ring the day before due to slippage. So what happened?
After searching the www, I came across someone who had the same problem 15 years ago! It was such a releaf to know it wasn't just me and that there was something going on here.
heres the original post from tarck: https://tarck.cc/t/mavic-ellipse-wheelset-problems/16868
So when I tried tightening the cog again, I realised that the lockring wasn't engaging the cog, even when I had it on mad tight! So the thread for the cog on the hub is somehow wider than the thread base of the cog I guess?
Anyways, I managed to get it to work using a spacer I found on a decomissioned track wheel, that fit right between the cog and the lockring. I think its important to use a metal spacer, as someone from the original thread on tarck used a plastic bb spacer, that got worn out after just a few skids (go figure).
So now that I had that fixed, there was A NEW PROBLEM! dangit:(
I dind't know if it happened when I tore off the cog going down hill or if I overtightened the cog and lockring. The latter is more likely as i was paranoid about having slippage again and did it up suuper tight.
So now the hub isn't running smoothly anymore and I really hope its just the dustcap thats bent and not the entire hub(or bearings) that got messed up. Has something simmilar ever happened to one of you guys? Overtightening seems viable because it is a aluminum hub, which is softer than steel.
Can I still ride it? Is ther anything I could do to diagnose the problem?
by DoucheBagBoy69
5 Comments
…wow the replies on the original tarck post you linked are brutal. Imagine asking for help and all people do is clown on you :/
glad you managed to save the situation.
first i would check for stripped threads on the hub, they’re probably toast.
can you upload photos when you take them apart?
(one addage for the spacer: i would put it between the hub and cog, not cog and lockring, somehow feels mechanically wrong)
wouldnt ride it
Ellipses are awful wheels, I’m not trying to be mean or clown you at all. it’s kinda just a fact. The cog spacing is a really annoying issue that pretty much everyone has and a French threaded lockring on a modern track wheelset is ridiculous.
What generally happens with these is people over tighten the axle bolts, and they end up snapping the pinch bolts and then overloading the bearings which results in pitting and a wheelset that increases bearing preload with installation. Or people strip the lockring threads all the time.
If I was you in this situation I would try to make sure they were safely rideable and offload them as soon as possible. If you really want to keep them, use spacers on the front of the cog between it and the lockring and just make sure you tighten the cog pretty tight, the lockring doesn’t need to be insanely tight as long as it’s there. Make sure none of the pinch bolts are stripped or cracked/ damaged any other way and just generally don’t go super crazy tightening stuff with these.
Ellipses are pretty delicate in pretty much all respects so just be easy on them.
I would run the spacer between the hub and sprocket, not sprocket and lockring.
Mavic Ellipse are designed as training wheels on the track, the spare set when everyone was running mavic comete disc and io 5 spoke. Having said that we’ve all seen so many pairs on the streets, people using brakes on them even when they don’t have a machined side wall, I personally have a set that I replaced the rear hub in due to a failure. Even though they are notorious they seem to be everywhere.