Bestrider Pump Pro 16: Slick Tire Upgrade

The Bestrider Pump Pro 16 came stock with MTB tires, which is very common on kids bikes. It is not that kids are using their bikes for off-road riding. Rather, it is due to the belief that knobbly MTB tires offer better traction, which reduces the chance of skidding and is thus safer for kids.

However, slick tires can actually offer good grip on pavement as well, as the contact area with the ground may be larger than knobbly tires, where only a few blocks are actually in contact with the smooth pavement. Unless the bike is really being used for some off-road riding, I think most kids bikes are actually better off using slick tires that have much lower rolling resistance.

In this case, this kids bike will not be used for off-road riding. It will only be used on pavement and PCN, and so a slick tire will provide a smoother and faster ride with less effort.

Therefore, I searched for a suitable slick tire in the 16 inch 305 wheel size, which is much less common than the 349 wheel size. I found that there is no slick tire in 305 size available from the big brands, such as Schwalbe and Continental. There are more models available from the Chinese brands, such as Kenda, CST, and etc.

However, I was surprised to find that these cheaper 305 tires are actually quite heavy. For a start, they are only available in wire bead types, which are heavier than those with kevlar beads that are only found on high end tires. Next, many of these tires are still knobbly MTB tires that are heavy, or semi-slick types with grooves and a thick rubber tread and sidewalls.

All of these 305 tires that I found are heavier than the much larger Continental GP5000 tires which are only 238 grams each. Of course, the width and price differs greatly, but what I found was that there is probably no market demand for a lightweight 305 slick tire.

Finally, I found a relatively lightweight 305 slick tire from CST, which stands for Cheng Shin Tire. Let's check out these new tires and compare it to the stock tires.

New 40-305 tires from CST. This brand is very common on mid-range to entry level bikes.

Relatively thinner sidewalls help to reduce the tire weight.

Claimed width is 40 mm or 1.50 inches. It will vary depending on the rim width.

Recommended tire pressure is 60 to 100 PSI, which seems very high given the width. Definitely can go lower if used on a kids bike.

Actual tread pattern, with a smooth centre tread and some side grooves. This was the smoothest 305 slick tire I could find.

Comparing it to the stock knobbly MTB tire, it is completely different!

Quite a big difference in tire width. Actual width to be shown later.

Stock tire is 305 grams. This is surprisingly light, as many of the 305 tires that I came across are heavier despite being less knobbly.

New CST tire is lighter at 260 grams. Still heavier than the much larger 700C GP5000 tire though, which makes me appreciate how much work went into making the lightweight race tires.

Stock inner tube with Schrader valves is 123 grams.

I took the chance to change the inner tubes as well, to use Presta valves instead. This would allow me to pump all the bike tires in my stable without having to change pump heads.

Slimmer inner tubes to match the slimmer tires.

New CST inner tubes with Presta valves are 102 grams each.

Since I will be replacing both the tires, I took the chance to weigh the front wheel as well. 413 grams for this 305 front wheel.

Instead of having a quick release axle pass through the hub axle, the wheel is bolted to the front fork by bolts on either side of the fork. Apparently this is a safety feature on kids bikes.

Stock MTB tire has a width of about 44 mm on the Inter-3 wheel, and 46 mm on the original wheel.

If the side knobs are included, the width is 49 mm. Even wider than my 650B gravel tires!

With the new CST slick tires, the tire width is greatly reduced to 36 mm.

As expected, the actual tire width differs from the claimed tire width of 40 mm, but it is OK. I think this width of 36 mm should be a good balance between low rolling resistance and also safety. Narrower tires for kids bikes are not ideal as they can get stuck in drain cover grilles or grooves in the ground, so I think 36 mm should be OK. For adult bikes, 28 mm road bike tires are common, but it requires attention to ensure that they are not trapped by drain cover grilles.

Outer tire diameter with the slick tires is 390 mm, smaller than the 400 mm with the knobbly tires.

With this change of tire, the effective tire diameter will become smaller, which translates to a lower gear ratio. Also, the slick tire will result in lower rolling resistance compared to the knobbly MTB tire.

Therefore, to maintain a similar gear ratio and to take advantage of the easier pedaling due to slick tires, I decided to change the rear sprocket size as well to ensure that the gearing does not become too light.

Previously I used an 18T sprocket, now a smaller 16T sprocket will be used to compensate for the tire change.

The smaller 16T sprocket saves a tiny bit of weight over the 18T sprocket.

Tire change is completed! Due to the change of sprocket size, I had to tension the chain by moving the rear wheel slightly further back, which requires the rear brake pads to be adjusted as well.

Slick tires on the front wheel as well.

Apart from the flashing due to the molding of the tire, the centreline is smooth with low rolling resistance.

Bike looks quite different with the slick tires. Now instead of looking rugged, it looks faster and more like a race bike.

With this tire change, the bike rides smoother, as I observed during our rides. Not only is it able to roll down slopes more easily without pedaling, the entire cycling experience is more enjoyable without having to work against unnecessary rolling resistance. At the same time, managed to save about 140 grams overall, which is a nice bonus.