Saturday, June 30, 2018

Crius AEV20 1x11: Shifters and Brakes

On this new 1x11 speed folding bike setup, the assembly is simplified because there is no left side shifter or front derailleur. Of course the gear range will be somewhat compromised, but since this is just for city riding, a relatively wide ratio 11-32T 11 speed rear cassette will be sufficient in most cases. This setup will be quite similar to the Dahon MuEX setup, with a 48T chainring and a 11-32T cassette.

As for 11 speed flat handlebar shifters for road, there is not much of a choice, unlike the previous 10 speed generation. For 10 speed road flat handlebar shifters, you could choose between the Tiagra SL-4600 or Ultegra-grade SL-R780 2x10 speed shifters. For 11 speed, the only choice is the non-series SL-RS700 2x10 speed road shifters.

These shifters work and feel exactly like the XTR SL-M9000 shifters, as they share the same construction. The changes are mainly internal, with different cable pitch as road and MTB cable pitch are not compatible.

Pair of non-series 2x11 speed flat handlebar shifters for road, SL-RS700

Slim clamp band, with 11 speed printed on the cover. I chose the black version of the clamp band (silver also available) to match the all black look of the bike.

Rather low profile, with a carbon main lever and a textured surface for more grip and tactile feeling.

Bottom view of the shifter

Although this will be a 1x11 speed setup, I cannot buy just the right side, I have to buy it as a pair. Therefore, the left side shifter will be unused.

Weight of right side SL-RS700 is just 105 grams, which is quite lightweight. 

To complement the all black look of the bike, of course I have to choose black coloured brake levers. For V brake levers, there is not much of a choice nowadays, as hydraulic brakes are getting more common. In fact, V brake levers and calipers are now categorized under Trekking instead of MTB.

For all black brake levers, I had a choice of Deore or LX brake levers. On the Dahon MuEX, I did use LX brake levers, so this time I wanted to put on Deore brake levers to see if there will be any difference. Another reason was that LX brake levers were out of stock.

Pair of Deore V brake levers, in all black.

Clean and simple appearance, which appeals to me.

It has an open clamp band design might be useful, if you want to change brake levers without removing the grips. Also I-Spec compatible, but this is an old I-Spec design.

Weight of pair of Deore V brake levers is 209 grams.

So is there any difference between Deore and LX brake levers? The answer is, very minimal. Other than being just 3 grams heavier, the Deore brake levers are also cheap at just $30 for a nice pair. The main difference for me is the surface finishing, where Deore is matte black while LX is gloss black. Either one will be a good choice.

Finally, moving on to the V brake calipers, I chose the LX brake calipers because, well, the Deore one was out of stock. My choices were quite simple, just choose the one that is in stock. Since they are all black in colour, the different brake lever and brake caliper will match anyway.

Pair of front and rear LX V brake calipers.

If you ever bought a pair of V brakes that come in a box, you may have noticed that there is a choice of Front or Rear. Actually, the parts are the same, the difference is how the brake pads are installed at the factory.

Front V brakes are installed facing the front, while rear V brakes are installed facing the rear. Therefore, the brake pads need to be installed in the correct direction to prevent the brake pads from flying out of the brake pad holders.

If you bought the "wrong" side, just swap the left and right brake pads and it will work fine, since the parts are all the same, just assembled differently for the customer's convenience of installation.

Each pair of brake calipers come with 2 mounting bolts, a curved brake noodle, and a rubber boot to keep out the dirt. The curvature of the brake noodle is the same for front or rear, although Avid does it differently.

Closer look at the brake calipers. Make sure you install the brake pads in the correct orientation!

Cable fixing bolt with a washer underneath to prevent the inner cable from fraying when you tighten the bolt. Hopefully these are rust resistant.

One pair of the brake calipers plus hardware is 184 grams. Multiply that by two to get 368 grams for one bike's worth of brake calipers.

With this, most of the components for this new folding bike is ready!

Wednesday, June 27, 2018

Crius AEV20 1x11: Drivetrain Selection

As I am building a folding bike from scratch, I can choose every component that will be assembled onto the bike. From the Crius frameset to the Wheelsport wheels, everything can be customized.

The drivetrain selection plays a big role in determining how well the bike will ride and shift. Therefore, I like to choose proven components that will work well, even though it may not be the lightest. There is usually also a budget constraint, so it cannot be the top level model as well, it needs to be affordable.

When I think of these three things: 1) Functions well / 2) Reasonable weight / 3) Affordable, the Shimano 105 groupset comes to my mind. Being the third tier road groupset, after Ultegra and Dura-Ace, it is relatively affordable, and yet performs well and close enough to the higher end components.

The newest 105 R7000 groupset was recently announced, and it looks to be really good. In fact, the all black finishing on the new R7000 will really match well with this bike's all-black theme. However, it is not available in the market yet, so I have to choose something else.

For choice of crankset, since this is going to be a 1x11 speed setup, I will go with a 105 5800 crankset, plus the proven Wolftooth Drop Stop narrow wide chainring, which I have used on the Dahon MuEX and the Java Freccia mini velo.

The Ultegra R8000 crankset seems to be all black also, but at twice the price of the outgoing 105 5800 crankset, I cannot justify the price difference. Besides, I am mainly using the crankarms only, the chainrings, however nice, will not be used for this 1x11 speed setup.

Right side crankarm alone weighs 340 grams.

Left side crankarm plus the plastic crank arm fixing bolt weighs 205 grams.

The full front single crankset thus weighs 655 grams. Not really lightweight, as there are lighter combinations out there. However, I like to stick to proven stuff that assembles and functions without fuss.

Wolftooth 48T Drop Stop chainring. Expensive stuff, but looks good and works really well.

All black, as requested!

105 5800 crankset with Wolftooth 48T chainring.

The cheap and good SM-BBR60 Hollowtech II road bottom bracket.

Moving to the rear derailleur, this is where I dared and wanted to pick something untested. I had a choice of picking the 105 5800 rear derailleur, which is affordable and good. However, I wondered how a Shadow road rear derailleur will look and function on a 20 inch folding bike?

The Shadow road rear derailleur was introduced with the latest generation of road bike groupsets, starting from Dura-Ace R9100, then to Ultegra R8000 and the new 105 R7000 series. However, as stated, R7000 was not available yet. Dura-Ace is all black, but out of the question as it is so much more expensive. That said, I did use the Dura-Ace R9150 Di2 rear derailleur on my road bike...

That leaves the only choice to be the Ultegra R8000 rear derailleur. Although I plan to use it with a 11-32T cassette, I chose the short cage version (which is rated up to 30T), so I hope it will work. I did not want to use the mid cage version as the longer cage might interfere with the wide Kojak tires.

Ultegra R8000 Shadow rear derailleur, short cage version. Looks very much like the mountain bike derailleurs.

With an interesting looking new cable adjust construction, designed to look slimmer to match road bikes.

You may have realised that many mountain bike Shadow rear derailleurs (Deore and above) do not have cable adjust bolts on the rear derailleur. This is because there is already a cable adjust bolt at the flat handlebar shifter, so the one on the rear derailleur can be left out.

However, on road drop bar shifters, there is no cable adjust bolt. So it is a good idea to have one on the rear derailleur, else an inline cable adjust will be required.

Very low side profile as you can see! This is the most outward position, and it is barely protruding from the bracket of the rear derailleur.

Black plastic sleeve to guide and protect the inner cable during shifting.

Cable fixing bolt

Weighs just 198 grams!

I am quite impressed with the low weight of the rear derailleur, because the Shadow construction looks rather chunky and looks like it might weigh more than the shorter cage Ultegra 6800 rear derailleur.

Comes with a special short length of outer casing, with a metal cap on one end and a cap with tongue on the other side.

The end with the metal cap needs to be inserted at the rear derailleur end, not the frame.

Instructions printed on the box of the rear derailleur. Should only cut the outer casing at the end with the plastic cap, not the metal cap.

The problem with this instructions is that I am unable to follow it when I build this folding bike. Since there will be a long full outer casing from the shifter to the rear derailleur, I cannot use this short section at all. Most likely I can only use the metal cap...

Finally, for good shifting performance, the choice of cassette is also crucial. As this is a front single setup, it is important to select a cassette with a wide enough range for city usage. This means a 11-32T or a 11-34T cassette.

As already mentioned in a separate post, the 11-34T cassette has a big jump from 11T to 13T, which is really not ideal for a comfortable gear step. This means the 11-32T cassette is the best choice for a relatively wide gear range.

Once again, I could choose between the 105 5800 or the Ultegra 6800 11-32T cassette. The main difference is weight and cost. I decided to get the cheaper 105 cassette as I already went over budget with the Ultegra R8000 rear derailleur...

105 5800 cassette uses a steel lockring instead of an aluminium one on the Ultegra cassette.

Number of gear teeth can be seen here. Coming down from 32T is 28T, 25T, 22T, 20T, 18T and so on.

Comes with a plastic holder which is useful if you know how to use it to slide the whole cassette onto the freehub body.

Only the largest three sprockets in the 105 cassette are mounted on the aluminium spider, the rest are individual sprockets.

Back of the aluminium spider. On the Dahon MuEX, I did a modification on the Ultegra cassette to fit the 11 speed cassette on the 10 speed freehub body, but it is not required here as an 11 speed freehub body is available.

Resin spacers are used instead of aluminium spacers. Material is PPS which is very compression-resistant. In fact, if you drop one on the floor, it sounds exactly like a metal part.

Weight of the 105 11-32T cassette is 305 grams. Just 25 grams heavier than the Ultegra version.

For a detailed comparison between 105 and Ultegra cassettes, check out this other post.

Next up will be the other components that will be installed on this bike, such as the brakes and the shifters.

Thursday, June 21, 2018

Crius AEV20 1x11: Wheelset and Tires

Regardless of the drivetrain selection or component specification, a good set of wheels is a must. Most stock wheels are of average quality and are quite heavy. For example, the stock D7 wheelset that came on my stock Dahon Boardwalk weighs over 1.6 kg, even though it was a low profile rim.

A custom wheelset is always possible, but that is just too much work for too little benefit. Besides, why bother when Wheelsport wheelsets are available for a reasonable price? Lower prices can also be found if you import your own wheelsets from overseas, but there is also risk involved.

For an all black look, the black Wheelsport Smart 1.0 wheelset was selected, for a good balance between appearance (30mm rim profile), function (aluminium brake track is better than carbon brake track anytime) and price (aluminium wheelset is more cost effective than carbon wheelset).

Of course, it has to be compatible to 11 speed, as that is part of the setup. A front 74mm and rear 130mm OLD model was selected to match the Crius frame. Also, a 406 wheelset was selected, to keep things simple and standard, as the frame was designed for 406 wheelsets.

The Crius frame can also take a 451 wheelset, but it will mean more weight (larger rims plus larger tires and inner tubes, plus V brake adapter) and more cost, while it also raises the bottom bracket by about 1 inch. It will also work but it is not necessary.

Wheelsport Smart 1.0 406 wheelset. The spoke pattern is attractive too!

30mm rim profile

About 19mm external rim width...

...and 13mm internal rim width.

Comes with rim tape already installed. I decided to just use the stock rim tape.

11 speed compatible freehub body. I think new wheels nowadays are all 11 speed compatible.

Front wheel weighs 531 grams.

Rear wheel weighs 751 grams.

This gives a total wheelset weight of 1282 grams (inclusive of rim tape), which is quite reasonable. A lighter build with lighter hubs and rims will probably be around 1100 grams. An extreme lightweight example would be the Kinetix Pro wheelset which is just below 1000 grams, but it is more expensive and is not 11 speed compatible.

Stock Wheelsport steel quick release axles, 74/130mm length.

Front 74mm QR axle weighs 51 grams

Rear 130mm QR axle weighs 59 grams

The pair of QR axles weigh 110 grams, which is considered heavy. It is easy to shave about 60 grams off by swapping to a pair of titanium QR axles.

As for the tires, I trust Schwalbe tires, which is why I went for the tried and trusted Schwalbe Kojak tires, 35-406 in size. The wider design is better for comfort and stability, while the bald tread ensures low rolling resistance and weight. A cheaper Kenda tire will probably work well too.

Pair of Kojak folding tires

239 grams for one tire, which is impressive given the 35mm width.

Schwalbe SV6 inner tube for 406 tires

Weighs 90 grams for one inner tube. A more lightweight SV6A inner tube would weigh around 65 grams.

During tire and tube installation, I found that the inner tube valve was a bit short, as the protrusion from the rim was too short for the pump head to attach properly. I had to get a valve extender, even though the rim height was only 30mm. Perhaps I should use an inner tube with a longer valve the next time.

Presta valve extender (for removable core type). It comes as a pair, with the red tool for tightening the extender and the valve core.

Here it how it fits. Remove the original valve core, and insert the extender in between. Obviously this only works for inner tubes with removable valve cores such as Schwalbe.

Final valve length. This is the 30mm extender, which looks quite long. A 20mm one is also available. It weighs practically nothing as it did not register on my weighing scale at all.

Wheelset with tires and inner tubes installed! Ready to be installed onto the bike frame.

Once the cassette is installed onto the rear hub, the wheelset can be assembled to the bike. After that, the rest of the drivetrain components can be installed!