The TITC inside line with Salton Dong – Day 2
While it was officially only Day 2 of racing at the TITC, for Hobbywing’s Salton Dong today (Friday) marked his seventh day in Thailand supporting drivers at the famous Bangkok race. With the bulk of his heavy work done earlier in the week in terms of testing and getting optimal ESC & motor settings dialled in for racing, catching up with Salton for a run down of what he got up to today would led to him to shedding some interesting light on driver’s motor habits and the playing of mind games with motor timing. In terms of dealing with any issues today, it was a massive crash in the top seeded heat third round qualifier of Open Brushless that had Salton busy at his work station located in the centre of the pits here at RC Addict. With Game Mongkolphan’s Xpress coming to an unexpected sudden stop on track, unfortunately there was no time for first on the scene Lukas Ellerbrock to react leading to a massive impact that left both cars heavily damaged. The aftermath gave the Awesomatix team 5-hours of work to completely rebuild Ellerbrock’s car for tomorrow’s final qualifier in which the overall TQ is still up for grabs. With both drivers involved running Hobbywing, the crash triggered Salton into action to assess the electrics of both cars, in particular the motors.
Salton explained, ‘In a big crash like this we check everything. With the ESC if there is no physical damage or no short circuit it will be fine but the motor is a physical part of the car so it is very important to check every part is not bent or not broken inside’. He continued, ‘After getting the motor out of the car we look for any visual damage and manually rotate the rotor, if it feels normal we need to open it to further check if it has broken the magnet inside. When we open the can we check the rotor, its physical state, the surface, everything. If it is good we put it aside and then check the front end bell and the rear end bell to see if these are bent, then if everything is OK we put it back together and plug it into the Tunalyzer to test the rotation. We then also compare the data with the motor’s standard data. We will have a basic benchmark for each type of motor so if there is a big difference that means there is something wrong’. Salton is keen to highlight this is something regular customers can also do themselves. ‘If they buy a new motor they can initially record the amp draw and the rpm to save it for future comparison and after some runs, if like the motor has overheated several times the magnets might be fading, if they are the KV will increase and the amp will go down, so this is a tip to try.’
Asked what is the most common reason for a motor to deteriorate, Salton replied, ‘If they are looked after they will have a very long life.’ Following that up then with the question, does he feel racers do look after them, he laughed and replied with, ‘most drivers just give their motors to me to check over.’ On the differences between Modified and Stock drivers attitude to motors he said, ‘because Modified has more power than is needed motor maintenance is overlooked where as in Stock you are chasing marginal gains so there is a need to keep motors well maintained and for that reason they get more attention from Stock drivers.’ Highlighting how important it is for Modified drivers to regular check their motors he said, ‘We found when rebuilding modified drivers’ motors the wear is much more than Stock because of the very high RPM. Normally the rotor shafts will show signs of wear, this is because of the super high RPM and this is why we have some basic rules on the FDR (final drive ratio) because we know the bearings highest RPM limit so we need to keep the motor in that RPM limit. If the gear ratio is too high, the RPM will also be high and over the limit.’
Being very diplomatic and not disclosing any names when asked which team drivers do better or worse when it comes to looking after their motors, he did say, ‘Modified guys I think they need to be careful, they need to actually rebuild their motors often because we always think ah brushless motors are zero maintenance and you can use them a long time but actually it’s not like a real electric car that you don’t need to go to the service. The bearing inside the motor usually has a max limit of 70,000 rpm but now in Modified Touring Car our motors are easily over 70,000 rpm so its already on the limit so that is why the shaft is sometimes wearing because it is rotating in the bearing and slipping.’
Asking Salton what is the most common thing customers come to him for, he said it is usually to do with setting the timing on the motor as many don’t feel confident in getting it right when it can be very critical. This led him on to a point about having the fastest car on the straight not being the key to being fast. ‘Lots of drivers will see a faster car on the straight and this gets into their head. Then they come to us saying my car is not fast enough but actually this (outright speed) is not the only thing to being faster, the 5-minute average is the most important. Our data is basically collected by team drivers. They test it over lots of 5-minutes and overall we will find a balance on the perfect timing and also for different batteries and different driving style they will also bring different results. So when a car passes you on the straight maybe it’s just one lap but it is the 5-minutes that counts.’ There are rumours that some drivers have played this mind game in testing here at the TITC, running 3-laps before pitting for a fresh battery for a second go at 3-laps to try get an impressive time on the board. Salton said in many case when they have turned up the speed on motors, many drivers return to get it reduced again because while the lap time might go down it compromises their overall performance as it drops off over the run.
