Michael Dunlop put down a marker ahead of Saturday's Dainese Superbike TT race with a sizzling lap at 131.501mph on Friday.

The BMW Motorrad rider set the fastest time of the week and Dunlop's lap was only 1.3 seconds outside the outright lap record of 131.671mph achieved by 20-time winner John McGuinness last year.

The 25-year-old was a four-time winner at the Isle of Man TT in 2013 as he boosted his tally to seven wins on the Mountain Course and has fired a timely warning to his rivals as the action gets under way in earnest on Saturday.

Dunlop's time was around six seconds faster than Bruce Anstey's best lap, who clocked 130.86mph on the Valvoline Padgett's Honda earlier in the week, and raises the potential for the first ever 132mph TT lap on Saturday.

Anstey was second fastest on Friday at 130.642mph with Tyco Suzuki's Guy Martin third in the Superbike class on the GSX-R1000 at 130.102mph, followed by Morecambe's McGuinness on the Honda Racing Fireblade, who lapped at 129.790mph.

Manx rider Dan Kneen set his best ever TT lap in Friday's final session with a speed of 129.107mph.

In the Superstock class, Gary Johnson on the Lincs Lifting Kawasaki recorded the fastest time in the class this week with a brilliant lap at 130.207mph.

Bradford's Dean Harrison on the RC Express Kawasaki was second fastest on Friday night at 129.990mph, with Michael Dunlop on his MD Racing BMW third quickest, lapping at 128.406mph. Quattro Plant Kawasaki's James Hillier was fourth fastest in the Superstock class at 127.448mph.

In the Supersport class, Johnson again led the way on the Smiths Triumph with a lap of 125.934mph with William Dunlop next on the Tyco Suzuki at 124.475mph. Friday's top three was completed by Keith Amor on the Rig Deluge Honda (124.356mph).

Milwaukee Yamaha's Josh Brookes set his best ever TT lap at 127.991mph, while newcomer Peter Hickman continues to impress on the Ice Valley BMW, lapping at 123.329mph.

A number of riders were involved in incidents on Friday evening, including Neil Champion, who suffered a spill at Greeba Castle but escaped with minor injuries.

Newcomer Callum Laidlaw was off at Governor's but reported as unhurt, while Northern Ireland's Shaun Anderson came off at Guthrie's Memorial and was treated by medics at the scene, but was also reported as okay.

The Dainese Superbike TT - won by Dunlop last year - is scheduled for an 11am start over six laps, with the first Sidecar race due off at 2pm over three laps on Saturday.