When done properly a belt drive is the most reliable way of doing it - especially in warmer countries where temperatures can be an issue with gearboxes. A belt drive NEEDS to be precise a few millimetres can take years off of the life of the pump and or engine. The technology is no different to the combine harvesters, until the last 10-15 years everything was belt driven due to the immense heat created by the machine. With belts it helps if you can keep the belts dry, and is not any different to your mower belts slipping in the wet during the spring months.
There has to be no flex in the frame, no side loading on the pump and the belt has to be tight. But most importantly 110% square.
Our base plate is done in 10mm steel for the belt drive - the design is checked and signed off by AMC for vibration rating and fail safe on the rubber mountings - I'm not saying Terry should take it that far but it wouldn't hurt, the bolt drilled up through the pump mounts at the end leaves no adjustment for the user, so what happens as the belts stretch? Our solution is well over engineered - but we have confidence in a zero chance of failure due to torsional stress on the larger engines. Loosing the odd Loncin or Aldi engine at £300 quid a go isn't the end of the world but losing a 2G40 at £3400 a pop would soon bring tears to your eyes. Especially if it could be avoided.
I don't know if you have seen the video he posted of building the machine with the belt drive
https://www.youtube.com/watch?v=UllelpEHi-U but I would say that anyone who thinks this video portrays the way a professional company should engineer and manufacture any product just goes to show that you get what you pay for.
I tell you now If I caught sophie or dave building something like this I would go absolutely ballistic!
They'd also not be building anything else!
