Tuesday, October 21, 2014

Lezyne Pressure Drive and Lezyne CO2 Trigger Drive

It is always a good idea to have the tools and spares to fix a puncture. Apart from the spare tube and the tire levers, a good portable hand pump is also essential. There are many different brands and types of hand pumps out there, but most of them are not that reliable or powerful enough for road bike tires. Road bike tires require high tire pressures of at least 100 PSI, and this is usually not achievable on normal hand pumps.

With the exception of the Lezyne Micro Floor Drive and other pumps of similar construction, all other hand pumps are unable to reach the high pressures required to pump up a road bike tire properly. However, an 80% inflated tire is better than a totally flat tire, as it still allows you to get somewhere even though it is slower and with more risk of getting a pinch flat.

The Lezyne Micro Floor Drive is powerful, but it just seems too big to fit nicely on the Merida Scultura 5000 road bike. Therefore I decided to get a slimmer and more compact hand pump for the road bike.

I have tried the Topeak RaceRocket Pump before, and this time I want to try a Lezyne hand pump. I selected the Lezyne Pressure Drive as it looks sleek and simple, and is not too expensive.

Lezyne Pressure Drive S size.. Rated up to a maximum pressure of 120 PSI.

It comes with a bracket for mounting the pump on the bike, using the bottle cage bosses.

Ingenious way of storing the hose inside the pump body itself.

The pump is about 190mm in length before extension

The hose is stored inside the pump cylinder itself, and can be accessed by opening a rubber cap at the top.

The hose can be pulled out fully. There are two ends of the hose for Presta and Schrader valves. One end attaches to the valve while the other end attaches to the pump body.

For example, if I am pumping a Presta valve, I will attach the Schrader end to the pump body by screwing in the hose to the bottom opening of the pump.

What I have done is to extract the hose from the top part of the pump, and screwed it into the bottom part of the pump. The hand pump is now ready to be used!

When fully extended, before compression, the pump length is actually very long!

The supplied mounting bracket is actually commonly used across many different models of Lezyne hand pumps.

The mounting bracket comes with a velcro strap as shown to secure the pump tightly to the bracket.


This particular model of hand pump also comes in two sizes, S and M. They are basically the same except for the length, which probably means that the M size pump has more volume per stroke.

Small sized pump weighs 91 grams without the mounting bracket.

Medium sized pump weighs 104 grams without the mounting bracket. 

The mounting bracket weighs 12 grams.

Ultimately, whichever hand pump you choose, the pump needs to be able to reach the minimum pressure required by the tire. On a MTB tire this is no problem as the pressure is much lower at 30-60 PSI, although it will take many more strokes. However, on a road bike tire where the minimum pressure required is usually about 90 PSI, this will be very challenging.

To test out the capability of the hand pump (and my arm strength), I tried to inflate the road bike tire using the Lezyne Pressure Drive, from zero PSI. At the start it was easy, but at around 50 PSI (estimated), it started to get really tough. It required a lot of strength to push one full stroke of air into the tube. I finally maxed out at 80 PSI (checked with a floor pump gauge) using this hand pump. Given my arm strength, I could not put in any more air as I am unable to compress the pump any more.

The 120 PSI rating on the pump refers to the quality of the seals in the hand pump, and that theoretically it is possible to reach 120 PSI if arm strength is not an issue. Realistically speaking, arm strength is the limiting factor here, as it comes a point where you will not be able to pump in any more air. Asking your buddy to take over and continue pumping may get a few more strokes of air in, but it will still be very tough.

Testing the max PSI that can be achieved with my effort alone.

Overall I would say that this Lezyne Pressure Drive hand pump does its job adequately, without being exceptionally outstanding. Given its lightweight construction and the compact size, I cannot possibly expect too much from it. Being able to achieve 80 PSI should be sufficient for me to continue riding after fixing the puncture.

Besides the Lezyne Pressure Drive hand pump, I will also be carrying the Lezyne CO2 Trigger Drive. This is a CO2 cartridge system that is used to inflate tires rapidly with minimum effort. It is popular among road cyclists due to it being more lightweight than hand pumps, and the quick inflation possible. The downside is that if you use the CO2 cartridge wrongly, it will be wasted, with the CO2 being discharged uselessly into the air. This would be a mini-disaster if you don't have a hand pump as a backup.

The Lezyne CO2 Trigger Drive comes with one 16 gram CO2 cartridge and the trigger. I bought an additional 16 gram cartridge as a spare.

This is the trigger that links the CO2 cartridge to the valve. It allows the flow of CO2 to be controlled so that the tire can be inflated properly.

The trigger needs to be used properly by attaching it to the valve and CO2 cartridge in the correct order, to avoid wasting the CO2 cartridge.

Weight of the CO2 cartridge. Although it says 16 grams at the side, this refers to the amount of CO2 inside the metal cylinder and not the weight of the CO2 cartridge.

The weight of the trigger is 26 grams, and the weight of the CO2 cartridge is 57 grams, giving a total weight of 83 grams. This is only 20 grams lighter than the Lezyne Pressure Drive + bracket shown above. There isn't really any significant weight savings if you choose a CO2 inflation system over a traditional hand pump.

However, the CO2 cartridge will be able to inflate the tire to 120 PSI when the pressurized CO2 is fully discharged from the cartridge into the tube. This will be better than the hand pump in the sense that it can achieve the required high tire pressure without any pumping effort.

I have not used a CO2 cartridge before, so this is new to me. Hopefully I will not need to use it, but in case I do, I hope I am able to use it properly! In any case there is always the hand pump as a backup.

In summary, with the combination of the Lezyne CO2 Trigger Drive and the Lezyne Pressure Drive hand pump, I will be able to deal with any punctures that may happen along the way. Overall these two systems add less than 200 grams to the bike weight which is still acceptable, given the importance of the hand pump and the CO2 system.

3 comments:

  1. What do you think about the difference and pros and cons between Topeak Pocket Rocket HP (mechanism similar to Non HP type) and Lezyne Pressure Drive? Both have their own supporter and points of unreliability as found on some online reviews. So it is a bit hard for me to choose. Required pressure is around 80 psi. Appreciate your input. Thank you

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    1. To be honest, I have not really used them much as they are only used when I get a puncture while out riding, which is not often. Both feature screw on pump heads which I like, and have flexible hoses which minimise stress on the valve.

      Both have a similar weight and length. However, the Lezyne pump does have a longer hose which may make it easier to hold the pump and get to a higher pressure.

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    2. Emm... Okay!! Thank you very much!

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