The Peugeot Remixed Part 2: Drivetrain

Now this was to be the main purpose of this upgrade, namely it was to lower the gearing to allow climbing up hills and also to overhaul the whole drivetrain to make it less noisy and draggy.  Originally the bike was equipped with a 10 speed derailleur setup and the intent was to replace the rear wheel with a 7 speed cassette setup and change the lower chainring for something lower.

However my partner who owns the bike was quite fond of the original Stronglight chainring pictured below with the 5 sided star pattern in the picture below.  This eventually led to abandoning the idea the derailleur setup for a hub gear...



Choices

What started this was the desire to keep the original chainrings on the bike, but the simplicity, low maintenance and ability to shift gears whilst stationary which mostly drove it.  Add to this that the overall cost was similar and this was not a hard decision to make.  The hub that was settled on was the Nexus 8 speed, in particular the SG-C6000 which is the model with roller clutch so the hub is completely silent without the freewheeling sound.  The hub came with a grip shift style shifter, this is the type that fits over the handlebars and requires the cylindrical grip to be rotated to shift gears, a bit like a motorcycle throttle.  However this wouldn't really fit with the handlebars and it was a bit too plasticy for a classic bike so the Alfine 8 speed trigger shifter was chosen which in theory should work with the Nexus hub.


Setup and installation

I've been fiddling with bikes for a while now, and I know very well now that fitting new parts ot old bikes is never particularly straightforward, there are likely to be surprises where things don't fit as you may think.  However the thing I knew from the outset was that the hub spacing would need a bit of a tweak.  The Nexus 8 speed hub is 130mm spaced from the factory, I had done my research and was aware that it was possible to respace it to at least 126mm.  The Peugeot, being an old bike 5 speed freewheel bike has a 120mm rear end spacing.  


The first thing to do is to remove the non-drive side locknut and dust cover, as this is the version of the hub meant for rim brakes, the dust cover reveals a spline type fitting meant to mate with a roller brake. 




There is a second locknut behind this which has a step in it meant for a bearing cover to fit into, I removed this and was left with the bearing cone which you can see in black below.  I found a replacement locknut which was a lot thinner and threaded this on, this made the overall spacing about 123mm which would mean that it should go right in without having to cold set the frame.  By the way, the Nexus axles are a bit different to Shimano hubs in that they are 9.5mm diameter and a 26tpi threading.













The wheel went in without any trouble and no stretching needed!  The supplied anti-rotation washers went in fine as well without any modification to the dropouts.

The sprocket goes onto the hub much like the Sturmey Archer hubs, there are a few tabs on the sprocket that mates with some slots on the hub and a circlip fits into a groove which holds it in place.



A little trim

As you can see from the picture above, there is a fair bit of axle still sticking out now, as I have removed the locknut and exposed more thread.  As the axle nut is closed on one end I can only tighten it so much before it bottoms out, so out comes the hacksaw...





I ended up removing about 10mm of the axle until it was about the right length, now everything was in place and it all looked like it could have come out of the factory like that.

Shifting setup

The stock twist shifter would not fit on the porteur style handlebars so we elected to go for an Alfine trigger shifter, this is styled much like the Shimano Rapidfire shifters, so there are two levers, one for the thumb and one for the index.  Having done some research though, I realised later that the Alfine 8 speed reversed the direction so it is low-normal; in the presence of no cable it defaults to a low gear.  The Nexus 8 is the other way around, however they cable pulls for each gear are more or less the same.

 The other thing I realised that was different was that the cable ends.  Because the Alfine is low-normal the shifting cassette rotates the opposite direction and therefore the nut at the end of the cable is also the other direction.  In addition the Alfine hub has a rubber boot, presumably because the cable runs slightly upward at the end instead of downward like the Nexus, water could accumulate in the low spot of the cable and cause rust and seizing.  Just using the Nexus nut on the cable worked fine.
  

The shifter was setup at the elbow of the handlebar which allows shifting when in more of a tuck position.  Luckily everything worked fine with the Nexus hub and Alfine shifter, the only difference is that the gear adjustment is set in gear 5 on the shifter (which is actually gear 4 on the hub), all the gears seem to work fine.


The stem was replaced with a vintage Milremo unit we got with Jackyll our Jack Taylor tandem which just needed a light sand to fit in the steerer.  The French steerers are 22.0mm whilst the standard British size is 22.2mm, this means you just need to sand enough to remove 0.1mm from the stem shaft.


Bar tape on and cork stoppers for bar plugs as we couldn't find the right bar plugs to fit.




Conclusion

All done! The hub works beautifully with very quick smooth shifts, even under load which a Sturmey Archer doesn't do at all.  The bike now rides along very quietly, getting rid of the derailleurs got rid of the chain slap and the noise of the pulleys.  My partner now has much more confidence to go down hills as the brakes actually work.  Also she loves the ability to shift when stationary which is perfect for commuting.  I'm quite impressed with the Nexus hub as it was really reasonably price and the sophisticated design inside is light years ahead to Sturmey Archer's which is what I'm used to.

Thanks for reading


2 comments:

  1. Wonderful! You are very handy. BTW, I think cork end plugs are the best! I use them also.

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  2. Excellent work! We have a similar Peugeot in our storage collection. It was my sister's college bike, way back when. I think a similar treatment would make it a great rider for her now. Thanks for the inspiration!

    Aaron

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