Advice re: 2 year-old agattu panasonic - Significant chain wear

[jackhandy]

"Popcorn Wholesale? Send me out some cases, there's a WD40 wrangle starting."

Don't blame me - It's not even my bike - I'm just "having a look" at it for an aquaintance

Just for the record - I use Barguard chainsaw oil on my bikes - Just because I can

 

[jackhandy]

Right then - Back on topic; for as long as it takes to read this, anyway

Just to confirm my measurements, which are as accurate as I can get 'em with my calipers & the sprockets still on the bike; measured at the base of the tooth:

Chainwheel = 2.12mm

Motor sprocket = 2.12mm

Rear sprocket = 2.10mm

Chain (between link cheeks) = 2.22mm

Chain roller width.....

Forgot to mention - the gears are, indeed, Nexus 8

Take 3.... The chainwheel is quite wobbly, although held in what I assume to be the correct position by a chunky circlip: I guess this is due to someone fitting a thinner sprocket than standard. I'll see if I can bodge a shim to go behind it, unless you think better left.

 

[flecc]

Those chainwheels are often a bit wobbly, and the motor sprocket can get a bit that way after a while.

Your measurement confirms that it is an up to 8 speed derailleur setup and not the usual 1/8" that single speed and hub motor bikes normally have.

I suspect this may be a rationalisation for manufacturers to keep stocks simple, one sprocket set for both types. As 50Hertz said earlier though, only 1/8" Nexus sprockets are usually available from common sources, so rear sprocket spares to keep the derailleur setup throughout may only be available from the e-bike manufacturers agents like 50cycles.

 

[50 Hertz]

I'd be interested to know if the rear sprocket sold by 50 Cycles is a 1/8". As far as I can see, no information is given on the 50C website regarding width. Would it be possible that 50C or Derby Cycles would have a bespoke sprocket manufactured?

 

[flecc]

It can't be a 1/8" sprocket with derailleur chain, it just wouldn't seat, sitting only on the narrows peaks of the teeth. It may be the Shimano sprockets are available to manufacturers in the narrower width, but not on the after market which is predominantly for unpowered bikes. Only the crank drive e-bikes would have a use for these narrower Nexus sprockets, so as an application, a minority of a minority market.

 

[Kudoscycles]

Sorry BAH48, but I disagree fundamentally. WD40 is not a lubricant! As avid completist readers of this forum may know, I acquired a Kalkhoff Pro-Connect S from another member in December 2012. On the 9th of April the chain parted going up a slight incline. After the chain was replaced, the transmission started slipping under load regularly. At the Edinburgh Cycle Company this was instantly diagnosed as significant wear in the rear cassette.

On back-tracking through this forum, I learned that the previous owner's 'lubricant' of choice was WD40. I find that describing WD40 as a 'lubricant' to professional cycle mechanics generally prompts slapping of the forehead, fierce oaths, hilarity or any combination of the three.

This is not a complaint about the bike I bought. (Caveat emptor). I reckon that replacing the chain and the rear cassette has improved the mechanical efficiency of the transmission by about 10 to 15%. I can tell that from both a higher top speed, and an increase in cruising speed of 1 to 2 mph without putting more effort in. My PC-S has gone from being a very good bike to being a great bike in my view.

If you go to the WD40 website, you'll read that "WD-40 literally stands for Water Displacement, 40th formula". Under FAQs about bikes the makers claim that "you can use it on frames to prevent them from rusting, to lubricate pivot points, to prevent mud from sticking and to displace moisture from bike components". Nothing about chains, though, and here's a quote from a website called Gizmodo: "while WD-40 is useful for everything from unsticking gum to cleaning tile, you shouldn't spray it anywhere near your bike. It causes dirt and dust to stick to your chain, turning it into a grody mess". That's my philosophy.

Incidentally the replacement chain on my PC-S is an especially long version for electric bikes made by KMC. Electric Bike Chains

It works fine, and there's no need to buy 2 shorter chains and join them.

I agree about WD40 not being a lubricant....the winch grinders on race yachts used to liberally pump WD40 into the grinders,ok for a short race but a nightmare for an overnighter. It causes the winches to clog up with white paste. The winch engineer after a race wanted to kill the grinders,except he was usually 8 stone and they were 20 stone gorillas!!!!!
KudosDave

 

[Cyclezee]

All the Panasonic transmission parts are available from 50c including the extra long 132 link chain Spares & Sprockets | Electric Bike Spares | 50cycles Ltd

 

[jackhandy]

Doesn't seem to say what width any of the chainset spares are, unless I've missed something.

Could be unfortunate if their standard kit is 1/8" as that fitted to the bike I'm working on is 3/32".

I'd have no option other than to fit a complete set.

 

[50 Hertz]

Doesn't seem to say what width any of the chainset spares are, unless I've missed something.

Could be unfortunate if their standard kit is 1/8" as that fitted to the bike I'm working on is 3/32".

I'd have no option other than to fit a complete set.

50 Cycles website gives no indication what size any of the sprockets are and from what I have read and the experiences that I have had, it can be a lottery.


You need to be careful, particularly with the motor drive sprocket. I don't know what the current situation is, but there used to be two different types a 1/8" one for the hub geared bikes and a 3/32" one for the bikes fitted with derailleur gears. Some unlucky derailleur geared bike owners were supplied with 1/8" motor drive sprockets and the 3/32" chain they were using started to snatch as it passed over the sprocket. There was a bit of discussion about it on here at the time.

A few months ago, I renewed all the sprockets and the chain on my bike. I purchased a new chain wheel, and motor sprocket and chain from 50 Cycles for my 8 Speed Alfine geared bike. They sent me a 3/32" chain which was too short and motor sprocket together with a chain wheel. I bought my rear sprocket from Wiggle, which will be a standard 1/8". So, I threw the 3/32" chain away and bought two lengths of 1/8" KMC and joined them to the correct length.

To clarify: I have 50C supplied chain wheel and motor sprocket (whatever size they are), a 1/8" KMC chain and a Shimano rear sprocket suited to an 8 Speed Nexus / Alfine hub gear.

I have been running this set-up for about 9 months and have done a few thousand miles. It is very smooth and quiet and I've had no problems.

 

[jackhandy]

Just a quick update & to say thanks for the help:

Ordered two 3/32" standard length KMC chains &used a speedlink to get the required length.

Tried without flipping the motor sprocket & all is smooth & quiet

Gave the mechanicals a bit of tlc & it rides nicely now.

On talking to the owner; she had a bucketload of problems with the supplier, resulting in a 6 month delay in actually getting the bike delivered, which may or may not explain why it's fitted with a non-standard chainset?

I won't name names, to avoid aggro. Knowing it's a touchy subject with some (infrequently posting) forum members