Strange behaviour with 12 year old Rohloff Thorne bike

[swayzak]

Hello

I have recently noticed that when changing to a lower gear (below 7), the gear fails to engage initially

This results in sudden loss of resistance when pedaling - so my feet suddenly lurch forward on the pedals

A bit disconcerting as often happens when changing down when starting an ascent

It is only momentary, but didn't used to happen

And idea what is causing this? Could the gear hub have developed a fault?

Thanks

[UKTony]

Ive not experienced this behaviour before but suggest you go to the following link

https://www.rohloff.de/en/service/handbook/faqs

then go to
>trouble shooting>free spinning (after a gear change)

which might help. If not then refer problem to Rohloff/Rohloff dealer.

[in4]

Gear change cable stretched a bit??
Check your chain tension too.

[swayzak]

Thanks both - will investigate further

[swayzak]

Tightened the chain and changed oil - seems to have fixed it!

Not sure whether one or both solved it though..

[UKTony]

👍 thanks for the feedback.

[GamblerGORD649]

Mine is 12 years old too, with 22,300 miles. I think it was sticky in 7th to 8th as well.
Last Sept. my Rohloff wheel was squeaking. It turned out to be the rim cracking. LOL.
But before that I took the shell apart. The whole insides had a goopy black coating stuck on everything. Wipes off easy but your can't get in all the nooks.
I spent 5 hours just cleaning it. Twice I sloshed it in solvent for half an hour. Still muck coated the inside parts. Three times I dug in there around the planet gear rings with 20 Q tips. And I used folded mail paper to pull thru the little gaps. This helped but still didn't get it all.
Next day I sloshed it again in Acetone, supposed to be a bad idea. LOL That washed out really tiny specks from somewhere.
 I think I got the gaskets nicely seated with a very THIN bit of sticky grease. The gasket is actually a thin plastic, not paper. The half inch gear in the Ex box only settles in with one of the six hex sides.
It needed a new seal on the brake side and changed it. Winter came and I didn't get to ride it far yet. Way better feel now. I did the axle whack trick too. One bearing has 2 retainer rings.

There's a guy on CGOAB has a 6 page post in forums showing how he rebuilt his hub. LOL. It got full of MUD riding crazy goat tracks in SE Asia during that biblical flood they had in Nov./ Dec. Lucky they quit early and went home. He also talks about the Rohloff not so special oil he had lab tested.

There's another YT guy with a really good 45 min. video where he rebuilt the oldest hub he could find. Shell bearings too. He's a machinist so he also lathed the jigs needed.

[UKTony]

I think it was sticky in 7th to 8th as well.

Changing gear from 7 to 8 and 8 to 7 can be a bit sticky. But it’s normal. There’s an explanation somewhere in the literature - either Rohloff’s or Thorn’s but I can’t put my finger on it at the moment. Maybe someone else on the forum knows where. My recollection is that it’s to do with changing between the lower and higher sets of planatory gears in the hub. For avoidance you need to back off pressure on the pedals a tad more when changing up or down between those two gears.