Tuesday, September 25, 2012

Expect the Unexpected: What Really Happened During the 128km Night Ride

Last Saturday night was my first tire puncture while out riding on the road, in about 4 years of cycling. In these 4 years, I have been really lucky, having never suffered a puncture while out riding.

During the 128km night ride, while riding into Punggol from Punggol Timor Island, we were going along the road where there are many stones and rocks on the road. We had almost cleared the area when I heard a loud *psshhttt*, and I immediately knew that my tire had gone flat. I stopped by the road side and found that my rear tire was flat. No worries, I thought. I am well equipped to replace the tube and keep going.

To my dismay, I found that the Kojak tire had a cut sidewall. Must have been caused by the tire riding through the stone minefield. Here is how it looks:

Looks like a small cut?

Actually it is quite a serious cut, I can see my fingernails through the hole.

For this kind of punctures, the first thing to do is to somehow patch up the hole on the tire. The only thing that was available was a dollar note, which is strong enough to cover the cut and prevent the tube from protruding through the hole. Many thanks to Boo for the $2 note!

With the note inserted between the new tube and the tire, and covering the cut, the makeshift patch seems to be working fine. Although the tube can be seen to be protruding slightly, it looked like the $2 note is strong enough not to tear.

And so we rode from Punggol, all the way to Changi Village and then along Changi Coastal Road. Just as we entered ECP from NSRCC, I suddenly had a funny feeling on the bike. I was pedaling normally, and holding the handlebar steady, but I just could not keep the bike going straight. It seemed to be wobbling around, with the steering feeling sluggish.

I stopped and took a look at the rear tire. Alamak, it was going flat again. The tire was not totally flat yet, but it was losing air. I tried pumping it up with the hand pump, but heard the dreaded hissing sound, coming from the same spot where the tire was cut previously. At that point I knew that my ride was over. I then told Boon Chun, who was with me as the group's sweeper, that I would not be able to go on. He then went on to chase down the rest of the group to relay the news to them.

Luckily, I was already near the ECP service road, and I pushed my bike to the service road. I was glad that I had George Kee's number, and I called him for help to pick me up. He was doing a great job covering our night ride as the support vehicle. Many thanks to George for the support!

And that was how I magically appeared at Big Splash, and then at West Coast Mac. Because of this incident, I only completed 80+km, 30km short of the complete route.

When I went to MyBikeShop yesterday, they had run out of the standard 20" Kojak tires. There were also no other 20" tires available except the Duranos. However, they did have the last pair of Limited Edition white wall Kojak tires. I guess those tires will have to do for now, else I would not even be able to ride the bike.

Limited Edition White Kojak Tires

A close up look at the white line running along the tire

While changing out the damaged Kojak tire and tube, I also analyzed what went wrong the second time it punctured. I found that there is actually an imprint of the plastic $2 note on the tube, along the outer edges of the note. In fact, the edges of the note are so sharp that some parts of the tube have been slightly cut by the note, although it did not go through. The actual puncture was found to be on one long edge of the note, near the middle. There was a crease in the note, and this crease actually formed a sharp ridge, that eventually poked a small hole in the tube! The $2 note that enabled me to cycle from Punggol to ECP was also the culprit that poked a hole in the tube. How ironic.

Lessons learned:
1) Avoid using a plastic note as an emergency tire boot, as the sharp edges will cut through the tube, sooner or later. The old paper note might work better.
2) Prepare an emergency tire boot kit, such as the one shown below. It will do a much better job of patching up the tire temporarily.
Park Tool Emergency Tire Boot

As for my new white Kojak tires, I have installed them on the bike.

 White Kojak tires on the gold Wheelsport rims. Quite a strange looking combination.

As seen on the bike

 Only the rear tire has been changed. Not sure if I should also change the front tire to the white Kojaks.

Although my bike is now working fine, somehow I feel that the looks of the white Kojak tires does not match the rest of the bike. What do you think?

Thursday, September 13, 2012

Wheelsport Rear Hub Maintenance Guide

Recently, I have seen many people upgrading their wheelset on their folding bikes. From 16" to 18" to 20" (406) and 20" (451), there are more upgrade choices than ever. Speaking in only the local context, there used to be only Kinetix Comp and Kinetix Pro 20" wheels for upgrade. Even then, it mainly fits Dahon bikes due to the narrower front hub OverLocknut Distance (OLD) of 74mm.

There was also the PZ Racing wheels, which are excellent wheels that roll very smoothly and makes a loud clicking sound which I like. The pair of PZ Racing wheels that I have are now on the Dahon Vitesse X20-TT.

When the Tyrell bikes were introduced in Singapore. they came with their own AM-3,5,7,9 wheels. However these were limited to front forks of standard 100mm OLD, and so could not be fitted onto Dahon folding bikes.

The lack of wheelset choices available locally was why I went to Taiwan last year to look for a new wheelset for my Dahon Boardwalk. When I was at Stripe Magic, I chanced upon the Wheelsport wheelset. It looked really well built with a 30mm rim profile, slightly taller than normal. It also came in a nice gold colour, which would really suit my Boardwalk! That was why I bought the wheelset there and brought it back to Singapore.

Barely one month after that, I found that MyBikeShop was also going to bring in those wheels! Me and Kian Lim also exchanged some tips on how to maintain the Wheelsport free hub. Seems like great minds think alike, we both found those wheels really attractive with a good performance.

So far, I have used those wheels extensively for over a year, and there has been no problems at all. The wheels have remained true so far, but that could have been helped by the mechanic in Taipei, who kindly tuned the spokes before packing it into a box for me.

Nowadays, there are many more wheelset choices available for small wheeled bikes. The Wheelsport wheels come in a variety of sizes, with different front hub widths to fit different forks. They also come in a few exciting colours to match your bike. The most common colours I have seen are Red and Black.

Other brands include LitePro wheels and Joseph Kuosac Carbon wheels, both brought in by Cyclopedia. I have not tried those wheels personally, but I know of quite a few people who have upgraded to those wheels and the feedback has been positive.

In view of the growing numbers of Wheelsport wheel users, I will share how to take apart the rear hub for maintenance, and most importantly, how to put it back!

The Wheelsport wheels use sealed bearing cartridges, and thus these sealed bearings will hardly ever need to be serviced. If for some reason the bearings are worn out, it will be best to just change out the whole bearing cartridge. For this maintenance guide, I will limit the maintenance to tasks that we can do with just normal tools, and thus we will not be removing any of the sealed bearings, which are press fitted.

Tools and Spares Required:
Size 5 Allen Key X 2
Special Grease for Freehub Body
Chain Whip (For removing cassette)
Cassette Tool + Large Wrench (For removing cassette)

Note: This only applies for the older version of Wheelsport rear hubs. For newer Wheelsport rear hubs, the construction is slightly different. Skip to the bottom of the page for more info about newer rear hub.

Step 1: Remove rear wheel from bike and remove cassette
I will not go into details on how to remove the cassette, this info is pretty much available on the Internet, a simple search on rear hub cassette removal will tell you all that you need to know and the tools you need.

Step 2: Loosen the axle nut on the non drive side of the rear hub
This is done by inserting a size 5 Allen key on either side of the axle. A slight torque should be enough to loosen the axle nut on the non drive side.

Step 3: Remove the axle nut on the non drive side
This should come out easily just by unscrewing the nut. Note the large hollow axle for good stiffness without excessive weight.

Step 4: Remove the locknut on the non drive side
The locknut comes with a rubber seal to seal against dirt and water ingression. Unscrew it to remove.

Step 5: Pull out freehub body plus axle
Once the 2 nuts on the non drive side has been removed, the freehub body plus axle should come out from the drive side easily.

Step 6: Clean ratchet and sealed bearing cover on rear hub
Clean the ratchet and the sealed bearing cover on the rear hub shell. There is no need to use degreaser, just use some toilet paper/rag and wipe the old dirty grease off. Degreaser might seep past the seals and remove the grease inside the bearing cartridge. Be careful not to leave bits of paper at the ratchet area. If all is well, the bearings should be smooth rolling.

Step 7: Remove spring and pawls from freehub body
Now, this part can be quite tricky. You may choose to skip this part if you are not sure how the pawls work.

The pawls are held in place by the circular spring as shown at the bottom left of the picture. It is actually a very long and slim coil spring that looks very much like a rubber band.

To remove the spring, just use a sharp object and gently lift it off one of the pawls. Be sure not to stretch it excessively. Slowly pull off the spring around the whole circumference. With this construction, the pawls are quite unlikely to fly away, but be careful in any case, as you don't want to lose any parts!

Clean all the parts by wiping the old grease off. If you obsess with cleanliness, you can use degreaser to clean them, but be sure to leave them to dry for a few hours to ensure that all the degreaser evaporates.

Step 8: Grease the freehub body at the area where the pawl seats, and reinstall the pawls
Dab some of the special grease for freehub body, and place the pawls back into place. Do not use the normal grease as it is too viscous and will cause the pawls to stick and not work properly. Oil is too light and will not last, although it will give you a very loud freewheeling clicking sound.

The pawls will stay in place as it is held there by the grease.

Step 9: Reinstall the spring
Carefully stretch and pull the spring over the pawls, making sure it seats properly in the slots. Make sure that the spring does not launch itself through the air! You may never see it again.

When done properly, all the pawls will then point outwards as shown. Ensure that each pawl is working properly by pressing the pawls down. The pawls should flick outwards smoothly.

Step 10: Grease the ratchet
Coat the ratchet area with the special grease for freehub body. Don't worry about the grease not being even, when the pawls move around the ratchet the grease will naturally be distributed evenly.

Step 11: Reinsert the freehub body plus axle
Insert the axle and make the freehub body sit into the ratchet. You may have to turn the freehub body a few times before it sits into the ratchet properly. Do not force it in, be gentle.

Step 12: Reinstall rubber seal on freehub body
This step is very important, do not miss this step! When the freehub body is inserted into the hub shell, the seal will naturally rest on the outside. This seal needs to be pushed in to rest under a lip on the hub shell.

Use a small flat tool to gently push the rubber seal under the lip as shown. If the seal is not seated properly, the hub sealing will be poor and there will be excessive friction.

Step 13: Reinstall the locknut and the axle nut
The locknut and axle nut should be screwed on the non drive side, hand tighten is sufficient. When the wheel is installed on the bike, the QR skewer will compress everything together and the parts will fit snugly.

Check that the wheel is spinning smoothly by holding up the wheel and spinning it. Also check that the freewheel mechanism is working smoothly. You will notice that the clicking sound will be softer due to the fresh grease cushioning the pawls. As the grease thins out and gets distributed, the clicking sound will regain its original level.

Step 14: Reinstall the cassette and put the wheel back on the bike

After the QR skewer has been tightened, the wheel should still spin smoothly.

That's all! It is actually quite simple and straight forward, without using any special jigs or tools to take apart the rear hub. Most rear hubs have a slightly different construction that differs from brand to brand, but the basic working principle is similar.

For newer Wheelsport rear hubs, the construction is slightly different. Most assembly and disassembly steps are the same, except for certain parts which cannot be removed like the older rear hubs.

If the freehub body comes off without the axle, that means that it is probably the newer rear hub.

If you want to remove the non-drive side axle caps, you can insert a Size 10 Allen Key into the axle, and then loosen the axle cap and locknut on the non-drive side with a Size 5 Allen Key and Size 17 Cone Wrench respectively.

After removing the axle cap and locknut on the non-drive side. I found that the axle is fixed to the sealed bearings and cannot be removed easily.

 Another difference is the construction of the pawls. There are now only 3 pawls instead of 6, and each of the 3 pawls have their own leaf spring, instead of one large coil spring for all 6 pawls in the older design.

This new pawl design can actually be more reliable, despite having only 3 pawls instead of 6. The reason is that although the old design has 6 pawls, they will all fail to work if the pawl spring breaks. On the other hand, for the new design, where the 3 pawls have individual springs, even if one of the pawl or spring breaks, the other 2 will still work.

I hope this guide has been useful, thank you for reading!

Wednesday, September 5, 2012

X Light 4 LED Safety Light Review

New lights for night cycling! I already have quite a number of lights on my bike already, which you can read about here.

Bicycle Lights for Night Riding
New Bar End Lights for Drop Bars

This time, I will be installing lights on my helmet. During a recent visit to Changi Village, I came across this particular light which works very well on helmets. My helmet has a Infini brand helmet light, but it is not working well as the switch has gone wonky.

I shall cut the long story short and introduce the light to you.

Nice packaging at a good price

All the different ways of mounting the light!

Some product info

All the velcro straps and clips for mounting the light to your bike or other places. Very well thought out.

Close up view of the light. 2 white and 2 red LEDs. All 4 LEDs point in 4 different directions.

Button at the rear of the light. Rather small and a bit fiddly.

I initially bought only 1 light, and planned to mount it right on top of the helmet, so that the white LED shines forward and the red LED shines rearwards. The other 2 white and red LEDs will then shine upwards (no purpose there).

However, mounting on the top is not ideal for me as the helmet shape means that the light is not projected horizontally forward or backwards. The light that shines upwards is also wasted. Then, I tried experimenting with other mounting positions, and found that when it is mounted on the side, all the 4 LEDs will be put to use effectively, as you will see from the pictures below. Thus I went to get a few more lights, 2 lights for each helmet.

 Lights mounted on the left and right side of the helmet

Side View. When worn on the head, the light will be parallel to the ground.

Front View

Rear View

Velcro mounting of the lights. I used my own velcro strip as it is more suitable.

 Rear View with the lights turned on. The LEDs are surprisingly bright!

Side View. Great side visibility!

Front View. It is actually bright enough to act as a head lamp if the object in front is close enough.

Actual brightness at night. 

Great all round visibility!

What is great about this light, when used as a pair of helmet lights, is that it gives all round visibility. For only $20, you get front lights, rear lights and side lights at the same time. This should not be your main lights, as the blinkers may be too small, but it is a great complement to your bike lights.

The lights are quite lightweight, I don't feel any additional weight on my head when I install them on the helmet.

With these lights, I have many lights to use when I cycle at night. For front lights, I have 1 S-Sun blinker, 1 B&M IXON IQ head light, and 2 white helmet lights. As for the rear, I have 1 Bontrager Flare rear light, 1 blue light, 2 bar end lights and 2 helmet lights. The helmet lights also provide 4 side lights, 2 on each side.

Too many lights? Maybe, but I would prefer to have more lights and make myself highly visible when I ride at night. I am not using powerful lights that blind other people, so it should be OK. What I have are mainly blinkers that let other people know that I am there. No excuse for not spotting me at night!