Not getting the right high voltage out the power supply

[Zipripper]

I used the Arduinix schematics to create a power-supply for my project, but there seems to be a problem with my design.
At the start of the 1k trimmer at 0% (0 Ohm) I have a voltage of 95Volts, when I start to increase the trimmer the voltage reaches about 140Volts after that the Voltage collapses to 95V again.
I watched the out signal of the NE555 and after the 140V the signal gets very unstable.

The next step i did was building the power supply on a breadboard because the most of the components on the PCB are SMD, but it got worse. The voltage does not get higher then 70-80Volts. All the components are connected as in the schematics and there are no faulty connections. I measured the signal on pin3 of the NE555 it stays between the 180 and 210Khz, and sometimes the coil L1 gets quite hot is this normal?

What goes wrong? I'am not an expert on electronics so is there someone that can help me or at least put me in the right direction?

Thanks in advanced,

[Zipripper]

Problem solved!!! stupid problem I must say, but solved . Because I made my own power supply from the Arduinix schematics I used a 5volt supply as input voltage. That was the reason the output voltage reached only 140Volts, after correcting this problem en raised the input voltage I got the correct output voltage .
For the problems that occurred on the breadboard, well the problem was the breadboard .