BIKETUBES 26 X 4.0"-4.5" TPU Tubes: Review Part 2

 Note: Guitar Ted purchased three BIKETUBES 26" X 4.0"-4.5" TPU tubes for test/review. BIKETUBES has no knowledge of this review previous to this post and all opinions are Guitar Ted's.

Image courtesy of BIKETUBES.

The TPU tubes for fat bikes which I am using were introduced a while back. That post can be read HERE in case you missed it. 

In this post I will be relating my first impressions and observations so far on how these tubes are doing with my riding so far here. 

Air Pressure:

I noted right away that the TPU fat bike tubes did not support the tires as well as the thicker, bulkier butyl tubes. These TPU tubes allow for a lot more tire flex and this can be seen two ways. 

One: It isn't maybe so great for some fat bike set ups and for using really low pressures for maximum flotation and traction. With a butyl tube the pressures can be run as low as almost zero and the tires tend to stay on and you can get maximum grip and flotation that way. However; I have to wonder if the TPU tubes either won't go to that extreme at even slightly higher pressures, or perhaps this is really all that needs to be done here. My instincts here are to say that I could do a similar thing as I could with a butyl tube, I just would not have to go so low in air pressure settings. 

Which leads me to number two: I needed to use a higher pressure to get a similar feel to what I was used to. Example: I would have never considered using anything higher than 10psi with a butyl tube. However; I not only am now using up to 10psi, I still don't see a similar feel to butyl tubes at this pressure compared to the 6psi - 8psi I used to use.And that is not a bad thing. The tires with TPU tubes feel amazingly smoother than with butyl rubber tubes in them.

Obviously (see image above) we just haven't had optimal conditions for snow/flotation. So, that low pressure thing will have to wait. I am pretty convinced that these tubes will be best if you shift your pressure ranges you are used to slightly higher. 

Finally, while other TPU tubes I've tried hold air quite well, these fat bike TPU tubes are not quite as good as what I expected in this regard. I noted that it only took about 3-4 days for my pressure to go from just under 10psi to about seven. That doesn't seem like much. Not even 3psi, right? But with a fat bike, 3psi is a huge difference. I plan on keeping a closer eye on this trait going forward. 

So, there might be a pressure holding issue and I don't like the valve stem design. That stem is just not robust enough and with no threaded/nut system to hold it against the rim, you have to be very careful with the stem as it is delicate. In fact, I have to wonder if using really low pressures might not cause a sheared valve stem problem. 

I'll be back with more in about a month or so. Stay tuned....