Testing
Pre testing period: From March through June 1963, the Royal (Dutch) Army has executed comparative testing of five brands of light motor cycles (200cc), viz. Triumph, BSA, Puch, Maico and Zündapp. The latter two were mounted with two stroke engines and because this resulted in the use of two stroke petrol, which was not available with the Army owned petrol stations, these two light motor cycles were reported to be inferior in an intermediate report in 1963. As a result of this report, testing of Maico and Zündapp motor bikes were stopped.
Because test series of Puch bikes were delivered to the Royal Army much later than Triumph and BSA bikes, and hence had not yet been sufficiently tested to draw justified conclusions concerning reliability during military use, testing of Puch bikes were continued. Testing of Triumph and BSA was continued as well despite of the fact that the conclusion was drawn that these bikes did not meet the requirements. There were however reasons to believe that after some minor modifications an acceptable life time could be achieved for both Triumph and BSA. This was the reason for continued testing of these Triumph and BSA machines.
In October 1963 the decision was made to discontinue testing of Puch, BSA and Triumph as well because: - After about 7,000 km Puch had run into serious piston damage. - the new air filters which were mounted on the BSA did not appear to be a sufficient improvement. - Triumph, besides damaged big ends, ran into piston damage, like BSA did, although with Triumph, piston damage occurred as early as after 8,000 km.
The table below shows the relative score, drafted after testing was completed.
Triumph had won this round, but this did not help much as the conclusion of the Vehicle Test Department was convincing, viz.:
1. all tested motor cycles showed: a. many minor deficiencies b. serious wear and tear with main parts, even after a relatively short runs (less than 10,000 km), requiring repairs to be executed by a higher echelon. 2. that achieving a sufficient longevity could not be realised through simple modifications.
************************************************************************ This lead to the decision that the Royal Army started comparative testing of heavier motor cycles in July1965 which ultimately resulted in purchasing 1,100 Triumph’s Model 3TA. ************************************************************************
Testing: As mentioned before, the Vehicle Testing Department started in 1965 with the comparison of three brands, the models Triumph 3TA, Matchless G3 and BSA B40. All mentioned motor cycles had a cylinder volume of 350 cc. Testing was done through a protocol, consisting of:
Testing took place in the workshop of the D.B.V. [Vehicle Testing Department] in The Hague, on the road and off the road, from March through July 1965 and has been carried out by D.B.V. personnel in cooperation with motor riders of the Military Police, lead by a Commanding Officer.
Tested motor bikes.
It is beyond the content of this website to quote the complete report, but the outcome of the tests carried out by the D.B.V. was the following:
Some of the advantages of the Triumph 3TA compared to the other brands were: - Larger ground clearance - Provided with steering damper, so the machine was easy to handle and very manoeuvrable in off the road situations. - Two cylinders, hence smooth running (BSA and Matchless were mounted with single cylinder engines) - Ease of maintenance - Longevity - Less weight.
A disadvantage of the 3TA, like the BSA, was, that a closed chain box was mounted, resulting in a chain box full with mud in case of off road use, leading to a reduced longevity of chain and chain wheels. Initial specifications required the weight of the bikes not to exceed 150 kilograms, but none of the machines met that requirement. Matchless even weighed 205 kilograms. An additional requirement was that the bikes were capable of achieving a speed of at least 140 km/h, but BSA, Matchless and Triumph were fare from meeting this requirement. They achieved a speed of 105, 115 and 118 km/h respectively, the 3TA being the fastest. The 3TA still had some minor things to be adapted but these were relatively easy so solve. It was proposed amongst others to replace the closed chain box of the Triumph 3TA by an open type. Matchless could meet the requirements after some modifications as well but BSA could not be turned into a suitable machine by the implementation of minor modifications.
Velocity testing in 1966
Meanwhile the Dutch Army had placed an order on December 14, 1965, with the importer of Triumph, R.S.Stokvis, and the first series was delivered in November 1966. Receiving inspection test results of the first regular series of improved motor bikes showed that the bikes had a “problem” in achieving the maximum obtained speed. Speed testing with the first bike of this series, done on October 19, 1966, resulted in a maximum speed of 103 km/h. As a result of this unexpected outcome and the big difference with the reported speed of prototypes in July 1965, it was found necessary to repeat the speed test with at least one bike. In addition Triumph Engineering Company Ltd was asked, in case the outcome of the test resulted in a speed of less than 118 km/h, to report the possible cause of this deficiency. Testing was repeated against elaborate protocols with the KS-01-63 (former KZ-99-55) on the landing strip of airport “Valkenburg”in Leiden. Achieved test results of an average speed of 110 km/h did not satisfy the D.B.V. It was decided to measure the compression ratio and to inspect the engine for wear and tear, which did not give satisfactory answers. It was decided to again execute additional testing, this time on air port “De Peel”, on December 6th, 1966. Results were disappointing: an average speed of 107.1 km/h. At the time the KS-01-63 was tested, an additional 16 3TA’s were tested for maximum speed.
It was ultimately concluded that 1965 and 1966 test results were hardly comparable, one of the reasons being the absence of 1965 data on test conditions, boundary conditions, variance, etc. The results of the 1965 test were assumed to be interpreted at the optimistic side at that time.
The reports clearly show that the speedometers of the 3TA read approximately 10 to 15 km/h too much at top speed and show furthermore that the maximum speed of 118 km/h, as specified in the technical specifications, is on the high side.
Sources: Royal Dutch Army Inspection Technical Department Vehicle Department Detachment Vehicle Testing Report DB nr. 186-05/B,January 1964 Report DB nr. 186-07, August 3, 1965 Report DB nr. 66.11.22-062, December 29, 1966 Foto's: LFFD
Copyright: Section Military History Royal Dutch Army
translation: Ben Geutskens
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