I'm dealing with this issue of chain drop after doing sprints/downhill. Not sure what's going on. What I've already checked:
1) chain is not worn over 0,5
2) changed the chainrings (did happen with alugear as well, but with worse shifting)
3) changed the wheel (it is even worse with my main wheelset – elitewheels drive helix)
4) changed the chainring offset (crank shims), tried setting different limits for FD
5) changed the tension on the RD (changed spring hole)
6) changed and tried more jockey wheels
I'm going crazy from this, because nothing seems to help. It is happening only in two smallest sprockets (11 and 12 t). It happens after i rapidly sit after sprinting, or going downhill (last time my chain got stuck between frame and chainring in 60+ kmh).
I think it has something to do with RD spring tension.
Or ist something else?
Has anyone experience with something similar?
Is the only option to swap the groupset?
by dzugy
25 Comments
I looks like it possibly you. Is the chain dry
Watch some Mark Cavendish sprints. Often crosses the line with a dropped chain. This is a natural effect of the friction of the freehub and momentum of pedaling fast and stopping. This happens on pro bikes that are taken care of meticulously with the highest level of components. A clutched derailleur may help, but less common to have on a road groupset. Not that there’s anything wrong with your groupset but I’d guess that brand isn’t helping, I can’t see what it is but doesn’t look mainstream. Lowering cassette weight and optimizing chain lubrication may help marginally. You may also be able to lubricate your freehub body with a thinner grease. But overall this problem will likely never go away completely from my knowledge.
Is this only happening when you rapidly stop pedaling and pedal backwards immediately afterwards? Because that motion won’t occur naturally on the bike.
You’re looking for a solution to a problem that doesn’t exist. Do you have any problems when actually riding the bike?
Have you checked the dropout alignment? See [https://www.parktool.com/en-int/product/derailleur-hanger-alignment-gauge-dag-2-2](https://www.parktool.com/en-int/product/derailleur-hanger-alignment-gauge-dag-2-2)
Ive had this with some bearings that were going on the free hub. The extra drag allowed the cassette to move a little bit after stopping pedaling. Riding solo it’s fine, but in a group ride, it would cause dropped chains as I pedaled then paused to maintain the gap in front of me.
I have only experienced anything like this when my chain is poorly lubed. Clean it to death and relube it.
I had similar and it was because I had greased the freehub pawls too much. I took the freehub back off, cleaned all the grease, and applied an oil to it instead. That solved my issue completely.
Your jerky back pedalling.
User error while on a bike stand.
rebuild the freehub. Clean it meticulously and use some nice thin grease. Replace your chain – I’ve found on the higher end chains (I use KMC x-ring 10sp) they don’t stretch even after thousands of miles, but they do start dropping.
The person operating the cranks
Are we all not gonna talk about making sure that those jockey wheels on the derailleur are spinning freely in all directions?
Possible issue friction in the freehub
Probably the hub pawls sticking
Freehub. What type of grease did you use when you last overhauled it? What type is specified? This is one of the few times white lithium grease shines over heavy marine grease.
Wtf are you doing?
literally bike circle jerking
Its just drag on your freehub. I bet you built that thing to be noisy with stiffer springs or your RD is on entry level without clutch or strong spring tension.
The motion is the biggest culprit, but an out of adjustment FD (if it has one I can’t tell) could be making it worse. The biggest issue I suspect is too many chain links. Did you install the chain, and if so, how?
My bike started doing this, I think the freehub had gotten a little sticky. I cleaned and lubed it, it did fix it.
Big heavy cassettes have a lot of inertia, that doesn’t help either
Freehub perhaps?
I had this issue when my freehub was going.
Also had one fail completely (it ate a pawl); suddenly I was on a fixie.
The behavior you show could be part of both cases.
Freehub is cooked/needs new bearings or is missing a washer to prevent the bearing from binding. If the chain comes off or goes slack like that it means there is resistance when freewheeling
Get better freehub bearings. Low friction ceramic bearings and use low viscosity oil for your pawls.
JFC…