Tire-Locs.

When going into the terrain, may it be in mud or rock terrain, it is always advisable to 'air down' the tires. This is to acheive the best possible traction under those conditions.

Problems:

1. By airing down the tire, it becomes lower, which will reduce the under-carriage clearance.
2. With a radically low air pressure in the tire, it might come off the rim. If this happens in the wrong place, it may take a lot of efforts to get out of the situation. Being lucky, there is an inner tube available. Otherwise, you are facing some deep trouble.

Solution:
By mounting Tire-Locs in the wheels, you may completely avoid those problems.

Tire-Loc is the name of a product produced in Sweden. It consists of three parts.

• A specially designed inner tube.
• An inliner (reminds of a bra) to keep the tube in place.
• A special ventilation 'flap' to be installed in the rim.

Note, that the installation of Tire-Locs requires that you make an additional hole in the rim. This makes the rim close to impossible to use without the Tire-Loc setup.

This is how it works:
A very low-profile inner tube is mounted in the tire, following the rim. It will have it's own air valve. The original air valve will be used to set the pressure in the tire itself. This way you will have one pressure in the tire and another, higher, pressure in the inner tube. To make sure that the inner tube does not expand to the inner size of the tire, it is kept in place by an inliner made of a mix of exotic materials, including kevlar. When the inliner is correctly mounted, the tube may, and should, expand sideways, thereby pushing the tire against the rim. It should not be able to expand in the peripheral direction. The special 'flap' is mounted so that the air can bypass the inner tube, going from it's air valve into the tire.

The result is that you can set the inner tube to, for instance, two kilos and keep the tire at three hundred grams (which is not a lot). Now the tire itself will be very flexible, keep an enormous surface against the ground, and still be very rigidly attached (by the inner tube) to the rim. Still, if the tire is compressed to a certain point, the tube inside the tire will stop the compression with it's higher air pressure.
As you probably already have realized, this can also give you some additional security for situations where you get a hole in the tire. You can still roll home, both in the terrain and on high-way. Of course, this should be done with considerably reduced speed, but it's possible. You're not 'stuck in a rut'.
Tests have been run where one tire have had no pressure at all, and only the inner tube have been pressurized. Under controlled conditions, the vehicle was driven in 120 km/hour. The result from the test was very positive.
Note!
Do not perform this test on your own, and especially not in public traffic. Consider this as a 'limp home' solution. Drive slowly, and take care!

To install Tire-Locs you will have to:

• Remove the tire from the rim.
• Drill a hole in the rim for the additional air valve. This valve is already mounted on the provided 'flap'.
• Remount tube, inliner and tire on the rim.

The result is remarkable. I have been riding whole days in the terrain (low speed) on three hundred grams, with two kilos in the inner tube. Everyone tells me that I will lose the tires, but I don't.

Drawbacks:

• It is a very unexpected sensation when the compression of the soft tires suddenly gets interrupted by the hard tube.
• It is very difficult to reverse the modification of the rim. Use an old rim if you are unsure.
• They are pricey.

So, how do you get them?

Since I bought my setup, Olle has created his own Web site. You may place your order on-line or search for a reseller near you. And of course, all technical details are available.

Don't forget to say hello to Olle from me. He's a friend of mine.
And, yes. English is spoken.

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