Pendleton Somerby Derailleur Cassette

[Namwaldog]

Hello,
My first posting.
I have a Pendleton Somerby bike, bought from Halfords about 3 years ago. I use it primarily with our motorhome. It has developed a niggly problem in that, occasionally, after freewheeling, I will start to pedal and the Derailleur cassette will spin freely on the hub offering no propulsion forward. However, whilst there is no mechanical propulsion, the 'electric assist' kicks in and the rear wheel still moves the bike forward!

I am a complete novice in the dark workings of bikes but feel, due to the intermittent nature of the problem, that perhaps some control adjustment is required? No Idea really, Grasping at straws!
Anyone encountered/fixed this problem?

Just to add. Once I give drive via the pedals/chain/cassette, it never fails. Only happens after freewheeling.
Thanks in anticipation.
Barry

 

[AGS]

It’s a shame you have a cassette rather than a freewheel.

From your description it looks like the free hub has gummed up with muck and the pawls aren’t engaging properly, so it needs to be cleaned out and regressed.

Here is a video of how to remove a cassette freehub from a motor.

Most of the budget motors use a freewheel instead of a cassette to reduce manufacturing cost, which are easier to remove and maintain.

So if you find you have a freewheel rather than a cassette here is a short clip of how to remove the freewheel.

And then you will be able to examine and clean the pawls that are inside the freewheel:

In both cases the pawls are designed to engage when you pedal forwards and disengage when you are freewheeling. If they get muck and dirt in them they can stick open and won’t engage when you pedal.

 

[Namwaldog]

Thanks for the reply. I shall have an investigate

 

[AGS]

I think you have a freewheel. Halfords ebikes don’t come with top end components, otherwise they wouldn’t be able to keep the cost down.

 

[Namwaldog]

Thanks again for your reply. It's a few years since I did any work on pedal bikes (think Sturmey Archer!)
I called it a cassette thinking that was what it was called! As said, I've no idea really but will take the back wheel out and have a dig around taking copious photos or videos as I go to aid reassembly
Thanks again.

 

[AGS]

Just post up a few photos if you get into trouble. A freewheel removal tool is only a few pounds from Halfords and a cassette removal tool is not much more expensive.

 

[Sturmey]

Thats a common problem. The cure is to put the bike (powered off) on its side on the floor with the freewheel facing upwards and pour plenty of 3 in 1 oil into the freewheel bearing that under the inside of the 13 speed cog while spinning the wheel to soften and flush out the solidified grease that seizing the pawls.

pendleton somerby electric bike

Hello, I am looking for some help/advice. I am new here and am hoping this is the right place for this. My electric bicycle, only moves when I pedal, but my pedaling action does not actually make the bike move, the rear sprocket seems to be spinning? Does this make sense to anyone? If I turn...

www.pedelecs.co.uk

 

[Bikes4two]

We had a Somerby for a while (and transformed the powered ride characteristics with a different controller - but not something the OP is likely to want to do but others might - LINK) and can confirm the rear sprockets are FREEWHEEL not cassette.

A replacment freewheel is cheap so if the OP is not inclined to want to try the first aid methods already described, then just replace it.

 

[Namwaldog]

Thanks for that.

 

[saneagle]

The 3 in one oil should fix it, but if it doesn't, you will have to get a new freewheel gear set. Unfortunately, Halfords don't stock them anymore, and you'll be lucky to get one anywhere else. No bike shop will have them, but they're often available from sellers on Amazon, Ebay and Aliexpress. It's a DNP 11/34 freewheel. 11 is the number of teeth on the smallest gear and 34 is the largest.

https://www.amazon.co.uk/DRIFT-MANIAC-Freewheel-11-28T-11-34T/dp/B07XYNSHZC/ref=asc_df_B07XYNSHZC/?tag=googshopuk-21&linkCode=df0&hvadid=394229352453&hvpos=&hvnetw=g&hvrand=6303228866386171641&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9045437&hvtargid=pla-862287976761&psc=1&tag=&ref=&adgrpid=87474904971&hvpone=&hvptwo=&hvadid=394229352453&hvpos=&hvnetw=g&hvrand=6303228866386171641&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9045437&hvtargid=pla-862287976761

 

[Namwaldog]

Thanks very much for this. Am I presuming correctly that the 3 in 1 oil needs to penetrate around these circumferances?

Just found this on YouTube so I'll give that a go first.

Thanks again.
Barry.

 

[Raboa]

One thing to bare in mind is that you need to make the freewheel tool centre diameter is big enough to fit over the ebike hub motor axle. Here's one that will, they is probably others that do as well.

Park Tool FR-1.3 Freewheel Remover

Park Tool FR-1.3 Freewheel Remover

www.balfesbikes.co.uk

 

[saneagle]

Thanks very much for this. Am I presuming correctly that the 3 in 1 oil needs to penetrate around these circumferances?View attachment 50662

Just found this on YouTube so I'll give that a go first.

Thanks again.
Barry.

No, that's just the outer cogs. Lay the bike over at 45 degrees and squirt the oil down the gap around the axle.

Look inside the hole in your picture. There's a join half way down. That's where the oil has to reach. Don't lean the bike all the way to horizontal because the oil will miss, though if you put enough in, it will fill up the hole and reach the join.

That YouTube video is incorrect for your freewheel, which is a special one and why you can't buy it from bike shops. The video one has the ratchet mechanism at the front. Yours is at the back because you have the small 11T top gear, which leaves no room for the mechanism.

 

[Sturmey]

Just to be specific, my daughters 2017 pendleton was fitted with a dnp 'epoch' 8 speed 13-32 tooth freewheel (similar to 28 version as as shown below). I suggest oiling as shown underneath the toothed locking ring so the oil flows through the ball bearings and on to the pawls inside the freewheel.
PS. This can be done without taking the wheel off the bike.

 

[saneagle]

Whatever version of rhe freewheel you have, if you need to buy a new one, get the 11/34 if you can, which is the best for climbing hills and gives the most comfortable pedalling when cruising. The 13T version makes you pedal too fast, so you can't keep up on any sort of downward incline. In fact if I had the 13/32 version, I'd change it even if it wasn't faulty. It's probably the best bang for buck improvement you can make for that bike.

 

[Namwaldog]

Just a quick update on this....

I found the easiest way to get oil into the freewheel was to put the bike up on to the workbench, put it on its side, freewheel up and support the whole bike with wooden blocks so that the crank could rotate freely.


The only place I could see to access the place to oil without removing the wheel was below the lower frame and above the derailleur changer. I could see where the freewheel was moving and the hub was stationary so aimed the 3 in 1 at the gap between and put 10-15 drops in and rotated the crank on both drive and freewheel.


I repeated this about 10 times. The drive engaged every time so hopefully I have managed to free up the gunk around the pawls.
Time will tell!
If this does not work, I shall, now armed with all the information kindly given by members in this thread, replace the freewheel.

Thanks again for all the help and advice given.

Barry

Edit...
As a novice, I found this YouTube video showing how freewheels are put together very useful...