I ordered some tyres for the road. I normally use Maxxi cross mark. This is a good solid tyre that I feel confident in Africa. I have done over 14000 km touring and training and never been up the creek without a paddle. However there are touring tyres more suited to the type of tour cycling I do. Now that I have written in for the Trans-Afrika I decided to try a narrower tyre more for paved roads. Most of the trans-Africa will be on paved roads.
Off with the Maxxis and on with a 38 mm slick. Thinking this was going to up my average speed. I chose a 47 km route that I had just recently done. However there was a little rain and wind. Using my heart rate I set out to compare the times. Much to my disappointment my average speed dropped by 1 km/h. Thinking this over I upped the tyre pressure to 75 Psi or 5 bar. Next night with conditions near perfect. Did the same route to find my time 1 km/h faster than with Maxxis.
Conclusion: Found handling little more difficult on gravel road up to house. In my mind I thought I was doing way better but in real terms there was not much difference. The weather conditions could make the difference. However if the tyres give 1 km/h better, that will result in just less than one day saving by the end of the Trans-Africa. Only the 38 mm tyres are not so rugged and may result in having to stop for tyre repairs along the way. There are times here in South Africa when the other road users are not so considerate and force you to exit the paving and ride on the gravel, stones and bushes along the side of the road. This my result in some damage to such a narrow tyre. With my Maxxis I will not even think of a problem.