bulbs 21w for front and rear indicators

[undercover]

ok i have my indicators flashing a little faster than they should be said the mot tester
problrm is this bloody powerbronze fairing has those nasty little indicators and i could only find
10w bulbs so i fitted 10w bulbs in the front
i have 21w in the rear indicators

now here is the question i have been told that it dosent matter what wattage they are it's only the electrical draw the bulb uses.
so does it matter what wattage bulbs i put in the front indicators or not
to slow down the flashing is it the fact i have 10w bulbs in the front indicators

i am confused 

[ssray]

You can get a `no load` flasher relay from halfords or you can add resistors to your current(geddit) bulbs, like you would if you fitted led bulbs
Ray

[undercover]

going to give this a try

www.ebay.co.uk/itm/180687673371?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649