Sub 11 Kg Dahon Mu P8

Dahon Mu p8 with all the latest upgrades now weighs less than 11Kg

My Dahon Mu P8 has been in service for over 5 years now.

It has now covered over 1000 miles in total, and it has required very minimal maintenance.

All of the modifications to the original specs have in the past included brakes, saddle and winter tyres. I also published about hints and tips to make life with the Dahon Mu P8 a breeze.

Those were the only changes I needed to make to increase the practicality and performance of my Mu P8 until 2014, when things changed.

I got a new job and my commute hasn't involved trains since.

This gave me the opportunity to make a few performance improvements aimed at reducing rolling resistance, increase efficiency, improve the gearing and make the bike lighter.

First of all, this latest version tips the scale at 10.8 Kg.

That means it's light enough to be taken into consideration as a substitute for a road bike when space is at premium, such as when travelling by plane or train over long distances.

It is also a much better looking bike, something not to hide in a corner but to put on show. It can now rival a Brompton.

But let's go through the list of improvements, one by one.

1) Remove rack and mudguards

Removing mudguards and rack really makes the bike sleeker, even when folded

This was not an easy decision to live with: without a rack, my only option is now to carry items in a rucksack.

But even more importantly, without mudguards there's a risk I will get wet from the back down, and that grime will foul the seat post.

I still haven't found a solution that I am happy with at the moment, so I decided I will only use my Mu P8 when the roads are dry.

Although I found something that might be worth it while browsing the web: the Zefal No Mud universal mudguards. I might have to give them a try.

2) Clipless pedals

Shimano M424 SPD pedals improve power transfer 

Originally I was considering a set of removable clipless pedals, like the MKS Ezy mm-Cube.

Unfortunately my budget wasn't allowing me to, so I decided to use a set of pedals I already had for touring, the Shimano A530.

That was a big mistake, since the flat part of the pedal is too slippery when wet, and I once went over the handle bars at a junction in London when my right foot slipped off the pedal while accelerating hard.

Since then, I have used these Shimano M424. They are not the lightest at over 500 grams, but are the safest I have used.

I might consider using SPD-SL pedals in the future since they provide a large enough platform to work with flat shoes, and normally weigh around 300 grams.

4) Grips

Ergon GC2 grips make aggressive riding more comfortable

Although the original Dahon grips were ergonomic, they lacked something when riding really fast: they were essentially not allowing a more aerodynamic riding position, torso flat with the ground, without discomfort, just like any flat bar grips.

These, the Ergon GC2 (now superseded by the Ergon GP2) provide enough of a bar end extension, to allow a more aggressive riding style and out of the saddle comfort. They also don't interfere with the folding mechanism being pretty compact.

5) Narrow tyres

Schwalbe Durano P 20x1.10 are fast, grippy and light.

The original Schwalbe Marathon Supreme 20x1.6 were excellent tyres, reliable (only one puncture in their lifetime on the streets of London) and probably still the best for this bike, since they allow lower inflation pressures and therefore greater comfort.

But, they weren't the fastest! These are! The Schwalbe Durano P 20x1.10

At 27 mm wide on the original Dahon Kinetix rims, they are light, grippy and fast. The Dahon Mu P8 now feels very similar to a Brompton, although maybe a little less precise due to the inherent flex in the steering column.

I inflate them to 60 PSI at the front and 80 PSI at the rear; this gives me the best balance between speed and comfort on British roads.

The ride is not too harsh, but you must pay more attention to the road conditions, in particular potholes. Since my primary use for this bike now is training rides when away for business, I really do think it is a price worth paying.

Finally) 9 Speed derailer and trigger shifter

Shimano Sora 9 speed derailer is reliable, fold after fold.

Deore trigger shifters are smooth and precise

I replaced the original and admittedly unreliable Neos 2.0 derailer and grip shifters, with a Shimano Sora rear derailer and Deore triggers.

This has made the biggest difference in terms of power transfer.

Going from 8 to 9 speed hasn't made a huge difference, although the more compact cassette (11-28T) now means smaller jumps between ratios, yet retaining a wide enough gear spread.

What had the biggest impact has been the more reliable shifting system provided by the Shimano road system.

The Sora derailer, the entry level of road components in the Shimano lineup, really does deliver consistent shifts fold after fold. There is no need to fiddle with the barrell adjuster anymore, and the trigger shifter delivers very crisps gear selections with minimal input.

Luckily again, this has not adversely impacted the bike folding mechanism.

A compact fold is still possible if using a short cage road derailer.

The derailer is  compact enough a sits pretty tight against the frame, therefore still allowing a compact footprint and reducing the chances of damage when storing the bike on its side or against a wall.

To be able to fit the new derailer a couple of modifications had to be made.

The first one was to fit a compatible derailer hanger (on the right in the picture below) in place of the face plate fitted at the factory (on the left in the picture below).

Not all Dahon bikes allow a derailer hanger to be fitted. The Mu P8 does.

For reference, I found the derailer hanger by visiting gearmechhanger.com and buying a D24 cast hanger.

The second modification was to take advantage of the hole left by removing the Neos derailer, and to clip the shifter cable to the frame: this allows the cable to follow a natural path to the derailer and won't foul the folding mechanism.

Routing the cable only requires a zip tie.

Conclusion

All of the above was absolutely unnecessary, but just so worth it!

Balloon tyres... (Schwalbe Marathon Supreme 26 x 2.0 folding tyres review)

I have recently fitted a set of large volume (balloon) tyres, a set of Schwalbe Marathon Supreme 26 x 2.0 folding tyres.





They replace my worn out set of Continental City Ride 26 x 1.5



The City Ride tyres were not great tyres at all: uncomfortable at high inflation pressures (70 psi), vague and slow at lower inflation pressures (40 psi), dreadful in the wet since new, with little traction on anything other than clean tarmac, and suffered greatly in lower temperatures (below 8 Celsius.)

But, they were cheap, and as far as puncture protection goes, they were very reliable: only one puncture in 12,000 miles. The rate of wear has been really great, probably explaining their reduced grip in cold and wet weather conditions.

Although the Marathon Supreme comes in both 1.6 and 2 inches wide models, I chose to try the 2 inches wide model on my commuter bike, and try a 'balloon' tyre for a change.

I am so far, pleased with my choice!



Before I expressed my opinion on the performance of the Marathon Supreme, let me tell you that a smaller (20 x 1.6) version of the same tyres are mounted on my folding Dahon Mu P8, and they have been great on that bike.

I must detail the type of riding I do, too. My hybrid bike is used for commuting duties, normally on London roads, and in the hilly part of the Kent countryside; it gets used for all sorts of other duties too: I go shopping and carry full panniers in excess of 20 Kg; I transport my daughter on a rear mounted bicycle seat, inclusive of panniers for day trips to the park; I ride on fire roads and trail tracks. And I expect reliability, handling, durability, and comfort.

Using this particular tyre, I can achieve all of the above objectives.

A large volume tyre allows lower inflation pressures without a great loss of rolling resistance. This comes at a price: rolling weight. But these tyres are not particular heavy even in the larger width, and therefore excel in providing the greater compliance and comfort of lower inflation pressures (40psi) yet resist to punctures and pinch flats, even on potholed roads.

The particular rubber compound used for these tyres is certainly more effective on wet roads than the City Ride tyres I used previously.



The carcass uses a higher TPI construction, which ensures compliance even at higher inflation pressures as required when carrying heavy loads.

The only caveat to be aware of is that these tyres are huge, and effectively increase the overall diameter of the wheel (total circumference 2050 mm): your gears will seem slightly longer as a result; please remember to adjust your cycle-computer accordingly.

A misdiagnosed loose cassette...

Recently I experienced mis-shifting and chain-jumping on my hybrid commuter bike.

At first I thought it might have been due to a worn out cassette; upon visual inspection, the cassette looked fine.

After a check of my riding records, I realised the chain had done about 1,600 miles and the cassette twice that; but a quick length check on the chain revealed little wear.

I then looked at the rear derailer from the back, and discovered the derailer cage was pointing inward, towards the wheel spokes. I had noticed this a long time before, and back at the time, I replaced the derailer hanger, but that made no difference.

I concluded a worn out derailer was to blame: no indexing attempt seemed to fix the shifting, especially between cogs 4, 5 and 6.

I bought a new chain and a new derailer from ChainReactionCycles.com. Replacing the chain regularly is good practice to ensure reduced wear on cassette and cranks. At 10 GBP for a KMC 8-speed chain with missing-link, it seemed a reasonable expence to face after 6 months riding.

The derailer, upon inspection, seemed to be slightly worn out too, and certainly had seen better days. The new Shimano Acera 8-speed rear derailer looked a worthy replacement for the old Shimano Tourney.




I began removing the old chain and derailer.

Then I removed the rear wheel from the frame to clean the cassette, and that's when I realised the cassette lock nut was not fully tightened and a couple of cogs were loose!

This was the reason behind the inconsistent shifting, and explained why any indexing correction was never lasting longer than a few miles, and why this was getting worse and worse with every passing day.

Unfortunately, I realised this too late. As I had forgotten my cassette tool in the office, I needed to borrow such tool. The guys at Cycles UK in Orpington quickly got it tightened for me for free.

After fitting the new chain and derailer, while I was tensing the gear cable inner wire, the wire snapped from the shifter!

The wire must have rusted near the insertion point and eventually broke off.



Luckily this happened while I was fixing the bike and I had all the tools with me. A second trip to the local Cycles UK shop and 2.99 GBP later, I had a brand new gear inner wire and was able to replace the old one.

This involved opening the 7-speed Shimano shifter and fitting the new wire in place of the old one.





Within minutes I was able to index the new derailer. 



A quick test ride later, I was very happy with the new setup and the new derailer provides crisper changes than the old one ever did even after fitting a new cassette and chain.

So even though the extra expense was not necessary, in the end it was all worth it.

I just wish that I had noticed the loose cassette sooner!

Riding a folding sofa

Today I fitted a very 'comfortable' saddle to my folding Dahon MUP8.
This was upon my wife's request due to my current saddle not being the correct size for her. This was the only other saddle I had available...

During a quick test ride to the high street to fetch some bike parts, it felt like riding a folding sofa!

The ride was way too soft, and the bike felt like wiggling side to side from underneath me. It also made the pedal strokes feel a lot less efficient, bobbing up and down with each power stroke.

The event confirmed to me how much difference a good saddle makes to the riding experience, as much as a good set of tyres makes to the handling.

Dahon Mu P8 performance tweak 2: a new saddle (Selle Italia C2)

After riding my Dahon Mu-P8 over several hundred miles, I can now reveal the second performance upgrade: I changed the stock saddle for a Selle Italia C2, bought from Wiggle.

Dahon Mu P8 performance tweak: brakes

Right from the start, the brake pads on my Dahon Mu P8 were quite noisy.