Execution time in programme

At the risk of looking stupid, please put me out of my misery and tell me what I'm not understanding. The following snippet of code is from a lap counter feeding a 7 segment display driver.

start_loop:
if stpin = 1 then
goto start_loop
endif

main_loop:
IF tkpin = 1 THEN GOTO main_loop
pause 25
cntr = cntr + 1
PULSOUT CLK, 500
if cntr = laps then
PULSOUT TIMER_EN, 5000
END
ELSE
goto wait_TKloop
endif

Laps are set earlier in the programme, say 10. When the 10th lap is signalled via TKPIN going low then the signal is debounced, counter incremented by one, a clock pulse sent forward to the next circuit and on the 10th lap the LAPS and CNTR are equal so a final stop signal is flagged and the programme ends. I have scoped the time delay between receiving the TKPIN pulse and the falling edge Pulsout at TIMER_EN. It is always TWICE the debounce time PAUSE plus a couple of mSecs. In the example shown it is 53mS. Why twice? I expected to see about 27mS. Why is this looping twice. I guess this is stupidly easy but I've gone dumb.
Adrian

Got it! I had a DEFINE OSC 8 line in the programme with a 4Mhz resonator! Duh!! Only taken me about 4 hours to find.....!!

Adrian