front disc limits
 

Is there a minimum disc limit for a mot test.

what thickness do you think discs should be replaced

normally found marked on the disc and can relate to several things like original disc thickness, disk material and also how far across the pads can come in the callipers

The disc were originally 5mm they are now 3.25 and 3.50.mm
There is a slight lip to edge of disc which i could remove easily

are they ok or should i replace

As Skidlids has said - there will be a wear limit stamped on the inner edge of the disc - most Ducs I've seen on standard discs are 4 or 4.5mm min thickness depending on them being 4.5 or 5mm thick when new as a guide.

Just checked the manual - ST4S new thickness 5mm +/- 0.1mm - wear limit 4.5mm!
Fink you need some new ones......

One of my sets of discs has a wear limit of 3.6mm. As you are quite away below this with one disc I would look at replacing them. There are Pairs of New Wavey discs going on Ebay for £149. My mate with the Powervalve engine in the Mito has just ordered some so waiting for his feedback on them.

Don't run around with overly worn discs. This happened braking for turn 15 @ Sepang on a track-day. The cast iron disc broke up and tore the caliper off the fork leg. Luckily there is lots of run off there.

Mike

Many thanks to all who replied I now know what i need to do. scrap the discs and get some new ones

bleedy hell mikey,that looks bad

im looking at those wavey disks too, some feedback would be good, i have emailed a previous buyer and he s said they look good and weigh a bit lighter than standard disks but he hasnt fitted them yet as its for a winter project bike

any news on these disks yet ??????

my front disks are measuring just over 3mm now, 22000 miles so its about time they were replaced for a bling set i think, wish i could afford the galfers but cant so the ebay ones will have to do