Impressions of the ICE TriceNT and the HP Velotechnik Scorpion.
Our weekend away with these trikes was a very interesting experience. Although as a result of this trip we decided that they were not going on our short-list for replacements for our old touring bikes, we still have some affection for this type of HPV. We handed them back with some regret and still would like to try these models again in the next year or so.
During the trip we discussed the pros and cons of each trike when compared with a normal bicycle and also when compared with each other. This 'review' aims to pull together these thoughts in a coherent way. It will look at the main features of both tricycle and compare them with each other. It will also compare the trike concept with our experience of cycling using traditional (and it has to be said very much cheaper) touring bikes.
Note I am not going to try to give a technical description of the trikes (dimensions, weights, wheel and tyre sizes, gear ratios etc) as 1) I didn't note these things down and 2) the manufacturer or dealer can supply this information if it is important to you and 3) specifications change, and these were probably not the latest models. So this is an overview of both trikes and our impressions of what in effect was an extended test.
Overview:
First impressions of the trikes was the size of them on the ground. Both were longer and wider than a two wheeled bike and a lot longer than the Bromptons we had cycled to the shop on. They were about as wide as each other the Trice being an NT (narrow track) version and approximately the same length as each other. The construction looked to be of a similar standard to aluminium framed bicycles and both trikes looked professionally put together. On moving them round they were surprisingly light bearing in mind they looked so large. The booms were adjusted to fit our leg lengths and we did not change them during the weekend as it seemed like too much work.In terms of the general design concept the two trikes are quite similar. The basis of both is a frame in the form of a cross, made from aluminium tubing of around 3 to 4 cm in diameter. The front boom carrying the chainwheel projects forward of the front wheels. The front wheels are quite far back, the rear of them is just in line with the handlebars. The handlebars are U shaped and in both cases positioned in a natural position. The rear wheel is suspended on both trikes, and a rear rack is mounted on the frame rather than the rear forks. Wheels are small (20") and only the front wheels have brakes on them and both trikes have a parking brake. The seats are attached to the main boom and are adjustable for rake, whilst the leg adjustments are achieved by the boom ahead of the front wheels being moved in or out as required. So far the similarities.
Now for the things that are not the same, firstly the obvious ones. (Click here for a larger annoted version of the images below). Starting with frames, seats and forks. At the front of the trikes there is a difference in the shape and form of the front outriggers carrying the front wheels. 
On the Trice these are perpendicular in the horizontal plane to the main boom. Looking from the front they are made of one piece of metal, and mounted on top of the main boom and swept up from the centre to the wheels.
The Scorpion's outriggers 
project forwards when looking from the top, are welded directly to the main boom and are straight. In terms of the frame design this Trice has an advantage here in that can be broken down further for transport than the Scorpion and the main boom can be split. We have ridden a newer version of the Scorpion with a fold in the middle of the main frame which addresses this issue to some degree (16/12/07 I just noticed today on the HP Velotechnik site that there is a folding version of the Scorpion that seems to fold as small as the Trice - one objection less to these HPV's).
The seats are both mounted towards the end for the bike and the backrest is partly over the rear wheel. No prizes for spotting the difference here: the Scorpion's shell seat versus the high-tech net covered 'deck-chair' arrangement on the Trice. Both of us were comfortable on our respective seats but I noticed that I had lots of problems with sweat on my back. After a half hour cycling the back of my T-shirt was wet purely because the moisture could not get away. Damae had no such problems with the Trice chair, which also did not fill up with water when it rained.