Sunday, December 23, 2018

Shimano Ultegra R8000 vs 6800: Brake Calipers

Although hydraulic disc brakes are becoming more popular on road bikes, traditional mechanical caliper brakes are still used on many bikes, as they are simpler to adjust for the home mechanic and also more lightweight than disc brake setups.

In some cases, it makes more sense to use caliper brakes, as they are more suitable. For example, on the Dahon MuSP folding bike, a standard reach caliper brake comes stock on the bike. This is best paired to a road shifter, which is why the Dahon MuSP is a good choice for a road drop bar setup.

During the previous generation of road caliper brakes from Shimano, a cam roller mechanism was used to enhance the braking performance of the brakes. This can be seen on the Dura-Ace 9000, Ultegra 6800 and 105 5800 caliper brakes.

This time, the new Ultegra R8000 brakes were used on the Dahon MuSP. Although it looks quite similar to the previous Ultegra 6800 brakes, there are some subtle but important differences. Let's compare and see what the differences are!

6800 = Ultegra 6800 caliper brakes (previous generation)
R8000 = Ultegra R8000 caliper brakes (latest generation)

6800 has silver coloured pivots, and the quick release lever points downwards when closed.

R8000 has a redesigned quick release lever, which tucks in neatly with the brake arm when closed. The pivots are also black in colour for a more stealthy look.

6800 has one bolt and one nut on the two pivots, both of which are silver in colour.

R8000 uses a slightly different construction, and has two nuts on the two pivots. Also black in colour like the bolts at the front of the brake.

6800 has a casted aluminium piece in the middle, which is part of the cam roller mechanism. The adjustment bolt (seen at top) means that a joint is visible.

For R8000, the cam roller mechanism has been redesigned to be a stamped steel part (black piece in the middle), which has a similar cam roller mechanism. The adjustment bolt has been moved to the side, which means that the top arm can be one single piece.

6800 has a spring tension adjustment bolt (small bolt just above the spring), which is not really necessary.

R8000 does not have a spring tension adjustment bolt, but it is OK as it is not important.

R8000 has an additional steel stiffening plate that links the left and right pivots together. This reduces the flexing of the brake arms during hard braking, which improves the braking performance. Although it adds weight, I think it is worth it for the performance boost.

R8000 has the adjustment bolt located at the side, which allows the whole brake caliper to look more integrated with less gaps.

6800 weighs 341 grams as a pair. Not so lightweight, but it has good braking performance.

R8000 actually weighs more at 362 grams, due to the additional steel stiffening plate.

In summary, the differences between the new Ultegra R8000 brake calipers and the previous Ultegra 6800 brake calipers:

1) Improved braking performance
2) More integrated look with less visible joints in the construction
3) Heavier by about 20 grams
4) Slightly darker shade of grey
5) Black coloured pivots

That's about it, with all other aspects looking the same as the previous generation. As already mentioned, these are rather subtle differences that enhances the appearance and also the performance, but at the expense of a bit more weight.

Saturday, December 8, 2018

Polygon Cozmic CX3.0: S-Ride 1x12 Speed, Maxxis Tires, ODI Grips

It has been 5 years since I bought the Polygon Cozmic CX3.0 mountain bike, and some components are way overdue for a change! For example, the tires are still the stock Kenda tires, and it is definitely time to change it after 5 years.

At the same time, I decided to install the 12 speed S-Ride upgrade kit, just to see how a 11-50T cassette feels like. As shown in detail in the previous post, this 11-50T 12 speed cassette can fit on a standard 9 spline freehub body, which means it can be installed on the my stock Shimano MT55 26" wheelset.

For the choice of new tires, there is not such a wide range of 26" tires available, as the market has mostly moved on to 27.5" and 29" wheels. Still, the range is wide enough to make it a tough choice to choose a new tire. After much research, I finally decided on the tires shown below.

I needed to take into account the tire width, as the latest generation of 26" tires are normally wider than the stock Kenda tires which are only 2.1" wide. Due to frame and fork limitations, it is not possible to run tires that are too wide.

Based on my visual estimation, there is enough space to fit in a 2.2" wide tire, instead of the stock 2.1" tire.

Maxxis Ardent Race tires, which is a good choice for most terrain, including some on-road riding. 2.2" wide which I think is the maximum that can be installed on my Polygon frame.

Some technical information on these tires. There are so many tire choices that it is hard to choose one.

679 grams per tire, which is on the heavy side for a 26" tire. Just for comparison, road bike tires are only about 260 grams each!

After removing the stock Kenda 2.1" tires, it is compared to the new Maxxis 2.2" tires.

Look at the big difference in width! The difference will be less once mounted on the rims. Not sure which tread pattern (along the central channel) will roll better on the road...

Comparing the new 2.2" Maxxis tires with the stock 2.1" Kenda tires, after mounting on the rims. Noticeable increase in width, hope it fits into the frame!

New Maxxis rear tire clearance with chain stays, only just enough! Less than a finger's width.

Front tire clearance with the arch on the front fork, also barely acceptable.

I am relieved that the new Maxxis Ardent Race tires, which are 2.2" in width, is able to fit my frame and fork. This extra width will provide extra grip when riding off road.

Other than new tires, I decided to get fresh grips as the previous grips were wearing out. No real need to change, but these new grips (as tested on other people's bikes) felt so much better in terms of grip and comfort, which was why I got new ones at the same time as the new Maxxis tires.

ODI Rogue lock on grips!

The clamps and bolts come unassembled. All the parts are the same, with no left/right or mirror designs.

Clamps and grips weigh 135 grams. Not for weight weenies...

To install the clamps, need to snap fit it over the ends of the grips.

The end caps also snap into the clamps. This needs to be done before installing the grips onto the handlebar.

Overall view of the grips

These grips have big chunky blocks that are soft and grippy, while the clamps are well designed. One little complaint is that the grips are exactly the same parts for left and right side, instead of being a mirror image of each other. This means that I cannot position them so that the clamp bolts and ODI logo are symmetrical on the bike. No function issue, just an aesthetic one.

Moving on to the new 12 speed drivetrain, the S-Ride rear derailleur requires a standard DATT hanger, which my Polygon mountain bike does not have. As previously shared, the Polygon comes with a Direct Mount hanger, which is good for Shimano mountain bike rear derailleurs but not others.

Therefore, if I wanted to use the S-Ride rear derailleur on the Polygon mountain bike, I needed to change the hanger to a DATT type. It may seem impossible to find, but I managed to find an online bike shop from Australia that has the hanger for my exact Polygon frame!

Comparing the stock Direct Mount hanger (left) with the new DATT hanger (right). Same mounting design to the frame.

The Direct Mount design places the attachment point further back, eliminating the need for an extra link on the rear derailleur.

Once the hanger has been switched, the rear derailleur could be installed without any problems. No problems either for cassette, shifter and chain installation. Let's see how the components look on the bike!

S-Ride rear derailleur, mounted on the new DATT hanger.

S-Ride rear derailleur. Looks quite good, except that it is not low profile like a Shadow rear derailleur. I also wonder how effective the clutch is.

The large 11-50T cassette mounted on the rear wheel, along with the 12 speed chain.

The new 12 speed drivetrain and the new Maxxis tires! Same SLX front single 34T crankset.

S-Ride 12 speed shifter installed! The gear display is nice to have, especially since there are so many gears on the cassette.

ODI Rogue grips installed. Looking good!

View of the full bike! The fresh, larger Maxxis tires makes the bike look new again!

How does the new gear range compare with the previous setup? Let's take a look.

Previous setup with 1x11 speed 11-46T cassette 

New setup with 1x12 speed 11-50T cassette

On this new 12 speed setup, there is a lower gear, courtesy of the large 50T sprocket. Other than that, the gear range and gear steps are similar to the previous 11 speed setup. In this case, the additional gear might not necessarily be better, as I give up the good performance of the Shimano 11 speed rear derailleur and shifter. In any case, it is worth trying out this 12 speed groupset which is not too expensive.

Saturday, December 1, 2018

S-Ride 12 Speed MTB Groupset

Are you riding a mountain bike? What drivetrain do you use on your mountain bike? In recent years, the mountain bike drivetrain has undergone a huge shift, from the traditional front triple system, to the front double system and finally to the front single system.

Last time, a front triple was necessary, because the rear cassette had a relatively narrow range (11-34T was considered large at that time), and limited number of speeds (8 or 9 speeds). A front triple was necessary to get the range required.

When 10 speed drivetrains appeared, it also came with wider range cassettes such as 11-36T. This enabled a front double system to achieve a similar gear range as traditional front triple systems.

After that, 11 speed MTB drivetrains were created by SRAM, which had a massive cassette range of 10-42T, which is a 420% range just from the cassette alone. That meant a front single drivetrain is usually sufficient, except for really low gears or really high gears. If you really want a 2x11 speed drivetrain, Shimano still has it for those who need the wider range.

Now, 12 speed drivetrains are becoming more popular, although the prices are still not so affordable yet. With 12 speeds on the cassette, a front single drivetrain can give you all the range you need for off road riding and also on road riding. Although the gear steps are still big, it is acceptable for off road riding where your cadence varies all the time anyway.

For the SRAM 11 and 12 speed cassettes, a special XD driver is needed on the rear hub, as the smallest sprocket is 10 teeth, which is too small to fit on a traditional 9 spline freehub body. This was an issue that slowed the adoption of SRAM's 11 and 12 speed cassettes.

XD Driver which was created by SRAM. The cassette is engaged to the splines only at the base, while the threads are used to tighten the cassette to the free hub body.

On the other hand, Shimano's 11 speed cassettes still used the common 9 spline freehub body, which is the same as those used for 8/9/10 speed cassettes. This means that a straight cassette swap on the same rear wheel is possible, although you still need to upgrade the other components such as shifter, rear derailleur and chain to 11 speeds. The downside to this is that the smallest sprocket is limited to 11 teeth, which means lesser range than SRAM's 10 teeth sprocket.

As mentioned earlier, a major stumbling block to mass adoption of wide range cassettes with 10T sprockets is the requirement for an XD driver. Many people are still using the traditional 9 spline freehub body and are reluctant to change the rear wheel. Unless you are getting a whole new bike with XD driver on the rear wheel, it is usually not cost effective to change the rear wheel as the old frame is probably not compatible anyway. For occasional off road riders like myself, I don't want to invest in a whole new mountain bike, but I still want to upgrade to more speeds.

So, if you are willing to give up the 10T sprocket, and settle for an 11T sprocket (and lesser range), it is possible to upgrade your drivetrain without changing your rear hub!

SRAM's Eagle cassette has a massive range of 10-50T, which is a huge range of 500%, and it is as big as a road chain ring. If you are willing to sacrifice a bit of range, and go for a 11-50T cassette, it can conceivably be installed on a normal 9 spline freehub body.

Although there are 11 or 12 speeds, the largest sprockets are suspended over the hub, as there is still space due to the dishing of the wheel and the spoke angle.

I came across this budget S-Ride 12 speed groupset, or more accurately, an upgrade kit. An upgrade kit does not have the crankset which you probably already have on your bike anyway.

With an affordable price of about $300, you can get a 1x12 speed drivetrain upgrade kit, which is a good way to try and see if you like the 12 speed setup or not.

Starting with the 11-50T 12 speed cassette, let's take a look at these components!

Massive 11-50T 12 speed cassette! Brand is Sunshine, which I have never heard of. Seems to be part of the S-Ride brand?

Only the two smallest sprockets (11T and 13T) are loose, the other 10 sprockets are riveted to each other or the aluminium spider.

Instead of using a lightweight (but expensive) one piece construction like SRAM's hollow cassettes, this cassette is made of stamped steel sprockets riveted together.

Sprocket sizes shown here (13-15-17-19-21). 11T not shown.

Continued (24-28-32-36-42-50), the gear steps are pretty big but OK for off road riding. Using some odd numbered gears might give a better gear step, but even numbered sprockets generally can provide better shifting performance.

Eye-catching red aluminium spider at the back!

The 4 largest sprockets (32-36-42-50) are riveted to this spider. The last 2 sprockets are also offset to be suspended behind the freehub body.

Another view of the spider and how it connects to the sprockets

For size comparison, this 11-50T cassette is almost as big as the Dura-Ace 53T road chain ring!

Due to the many sprockets and lower cost stamped steel construction, this cassette weighs 596 grams which is heavy.

The highlight and most important part of this groupset is undoubtedly the gigantic 11-50T cassette. Let's see what the other components are.

12 speed chain, comes with a set of quick links!

This chain is made by YBN which is a big chain manufacturer. No worries about quality here.

Weighs 260 grams with the plastic packaging and before cutting to length.

As for the rear derailleur, it needs to cater for the 11-50T range of the cassette, both in terms of chain capacity and also the parallelogram angle. Curiously enough, this S-Ride rear derailleur comes with a choice of clutch and non-clutch versions. For off road riding, a clutch version is definitely better as it stabilizes the chain to prevent chain drop.

S-Ride rear derailleur for 12 speed, with clutch. The "C" behind the model number RD-M500 signifies the clutch version. Other than that, there is no other obvious way to tell if it is a clutch version or not. No clutch adjustment is possible.

This rear derailleur construction is the traditional road type, not the Shadow type of mountain bike rear derailleur which has a lower profile to avoid damage.

Outer casing stopper located here, which is quite similar to SRAM's design.

When in the top gear position, the rear derailleur sticks out quite a bit as can be seen here. More prone to damage if you ride near rocks. Also note the steep parallelogram angle, which is needed to reach the large 50T sprocket.

High and Low limit screws are located on the outer link of the rear derailleur.

Resin cable guide to route the inner cable towards the cable fixing bolt.

Long cage is necessary to take up the chain slack across the large 11-50T cassette.

Weighs 265 grams, which is surprisingly light weight, as it is similar in weight to the Deore XT M8000 rear derailleur.

Finally, the 12 speed shifter, to move the rear derailleur across the 12 gears on the cassette. This is the contact point between the rider and the drivetrain, so it is important to get the shifter right.

S-Ride 12 speed shifter, looking like a blend between Shimano and SRAM shifters.

12 Speed feature indicated boldly on the cover

Comes with a gear display, which I personally like. Although it is not necessary when riding in the trail, it is nice to have a reference from time to time, as I tend to get lost in the multiple gears.

The unique lever which allows push or pull release action. Works differently from Shimano's 2-way release design.

Bottom view looks totally like a SRAM shifter. Shift levers are steel plates encapsulated in plastic.

 After removing the covers, here is how the release lever works. It pivots around the centre when you push or pull the release lever, which engages another plate to release the gear.

 One interesting thing about the clamp band is that the mechanism is only secured to the clamp band when you tighten it on a handlebar. Otherwise it is just floating...

Shifting feeling wise, it is not the best, as it feels rather plasticky, much like most of SRAM's shifters. The release lever also rattles, as there is no additional spring to take up the play. Otherwise, shifting function is OK.

Shifter weighs a competitive 108 grams, which is mainly due to the use of plastic parts which are lightweight and also cheaper than aluminium parts.

View of the upgrade kit! Looks pretty decent.

The quality of the components are quite OK, but it will finally depend on the shifting performance when mounted on the bike. The most important thing is that it fits on a normal (outdated?) mountain bike, which is my Polygon Cozmic CX3.0. Although I don't ride it often, this new 12 speed groupset gives me the chance to ride and test out the S-Ride components.

In another post, I will show the components mounted on the mountain bike, along with a few other new parts!