Isle of Man Lightweight TT Road Bikes Test

Michael Mann - Web Editor, Bike Social
By Michael Mann
MannOnABike Web editor of Bike Social. Been riding bikes since he was four-years-old. Fast and smooth road rider, just about hangs on in a track day quick group.

The Isle of Man Lightweight TT Group Test: 2016 Suzuki SV650 vs Kawasaki ER-6n vs WK 650i vs Yamaha MT-07


With so much bike for relatively little cash, it's no surprise that the 650 twins have also spawned a TT race class of their own - the Bennetts Lightweight TT.

On the week of the Lightweight TT race we pit Suzuki's new SV650, Kawasaki's ER-6n, WK's 650i and throw in Yamaha's slightly bigger capacity MT-07 on the Isle of Man Mountain Course.

With so much bike for relatively little cash, it's no surprise that the venerable 650 twins have also spawned a TT race class of their own - the Bennetts Lightweight TT.On the week of the Lightweight TT race we pit Suzuki's new SV650, Kawasaki's ER-6n, WK's 650i and threw in Yamaha's slightly bigger capacity MT-07 as a wildcard on the Isle of Man Mountain Course.

Isle of Man TT legend, John McGuinness, calls it the 'shopping bike race' but the top riders of the race-spec Lightweight TT bikes can average over 120mph around the iconic 37.73 mile Mountain Course. WIth the arrival of Suzuki's new SV650 and the Lightweight TT kicking off on Wednesday,  it was the perfect reason to pitch the Suzuki against it's more established rivals on the open roads of the Isle of Man Mountain Course.

Slower than full-bore superbikes they may be, but the Lightweight TT lap record is held by James Hillier whose lap in 2015 of 120.848mph is only 2.8mph shy of Carl Fogarty’s outright lap record set 1992 – which stood for seven years on a 750 Yamaha OW-01. That fact that in standard form any of them struggle to top 130mph over the Mountain makes that lap seem even more incredible.

Quattro Plant Kawasaki's James Hillier on his way to the lap record in 2015

The regulations state that entries in the Lightweight TT must have water-cooled, four-stroke, twin cylinder engines not exceeding 650 cc. However, for our group test the wildcard is the Yamaha MT-07.

Suzuki SV650 - new for 2016Kawasaki's ER-6n is uber popular among the Lightweight TT racersWK 650i from CF MotoThe Wildcard: Yamaha's MT-07

The Yamaha is one of the best modern motorcycles on the market, has dominated sales charts in recent years and is seen as the class-leading machine for this sector of the market; A2-licence friendly and an ideal first so-called ‘big bike’, commuter or as a quick, comfortable and capable alternative if the knees can’t hack a sports bike anymore.

Lightweight Isle of Man TT-winner turned Rider Liaison Officer, Richard Quayle, is better known as ‘Milky’ and his knowledge of the Mountain Course is second to none. He knows every bump, braking point, kerb and telegraph pole and to say he is enthusiastic about his homeland is an understatement. We signed him up not only for his experience around the Island but also for his riding ability as a fourth tester alongside Bike Social regulars Marc Potter (ex-MCN Editor, 6’4”, one of the world’s most experienced road testers), Paul Taylor (40-something, 5’4”, a more sedate rider) and I (30-something, 6’, range of riding experience).

Before we’d ridden anywhere Milky had already reminded us that while the race bikes may be named after the road-going versions and bear some resemblance, actually there’s around £15-20,000 worth of upgrades to the engine fairing, suspension, brakes and gearbox for the race bikes to get anywhere near a 120mph average lap speed. The irony is that along the unrestricted mountain section of the circuit a pinned throttle in top gear would only just achieve an indicated 128mph from the Kawasaki and 131mph from the WK. That said, for your £20k you do end up with nearer to 100bhp than the stock 71bhp of the ER6n.

The shopping was left to those with four wheels and a boot as we took off from the pit lane to join the famous Glencrutchery Road to lap the Mountain Course to see just how good these versatile nakeds are.

The road-going middleweights at Ginger Hall

YAMAHA MT-07 - £5749

By far the most attractive, polished and refined looking bike of the foursome especially in Matt Grey, one of four colours available. As we know it’s also the winner in terms of sales too. At a little over five-grand, the MT-07 offers excellent value for those looking for an accessible, easy to ride bike designed for young and inexperienced riders, while providing enough go to appeal to lifelong motorcyclists.

The parallel twin 689cc engine in the Japanese machine packs a spirited performance especially in the low and mid range. Its throttle action is perfectly light, responsive and manageable, lively without being too aggressive. You would be forgiven for thinking this is a cheap, commuter hack but its far from it. Unveiled two years ago, it’s now being taken seriously as an economical multi-purpose bike that punches well above its weight.

Mann on an MT Mission at Glen Helen

From as low as 2500rpm the torque picks up nicely, puling with a clean and strong spread of grunt. The Yamaha has the highest torque figure (50 ft-lbs at 6500rpm) while making its maximum at the lowest revs compared to the three rivals.

The fun begins as its legs are stretched. While ideal as a city cruiser given its comfort and practicality, the accomplished chassis and its light weight (at 182kg, its 15kg lower than its nearest rival, the Suzuki) makes the Yamaha a highly proficient and agile B-road thriller as well. It has the tallest seat height of the four at 805mm, equal with the Kawasaki, but because of its narrow seat and well positioned pegs, it’s the most comfortable to ride.

Fine, it runs out of puff a bit at the top but it's not a bike designed to challenge R6s and CBR600s – performance wise the four were very similar when let loose over the mountain section with its unrestricted speed limit. The Yamaha’s smart LCD display showing 129mph.

While Milky and Potski honed in on the suspensions spongy feel, I’d give it the benefit of the doubt especially considering the target audience and type of riding likely to befit the MT-07 – instead of journalists seeing how effective slipstream is at maximum speed! But this is a test on the Isle of Man and that was their feedback.

The Yamaha is fitted with Bridgestone Battlax BT023 which offer ideal levels of grip for this style of bike and will be suitably durable too.

Second opinion – Marc Potter

Potter heads to the Gooseneck on the Yamaha MT-07

The classiest looking bike of the bunch with some incredible features for the money – just look at the finish on the paint, the nicely trimmed plastic protectors, the mudguards, the engine. It’s a beautifully polished package with the most low-range and mid-range punch, the smoothest motor and the best brakes. But for me the brilliant MT-07 is let down by suspension that belongs on an eighties trail bike once you start going fast on it. Okay, the TT course is the harshest test of a bike being ridden quickly, and around town the soft suspension is fine. But stick a pillion on the back and it’s like the bike has zero damping. It’s a real shame because in every other way the MT-07 is the best bike here.

SUZUKI SV650 - £5499

After reading the press reviews following the launch earlier this year I was keen to ride the Suzuki. Helped by being a V-twin fan, I suspect. And it didn’t disappoint.

The SVF650 Gladius replaced the last naked SV650 back in ’08. Until now. The latest version features 140 chassis changes and a further 40 new engine components to the outgoing Gladius. It lost 8kg and gained 5bhp too, all of which has transformed the middleweight naked making it not only nimbler but more torquey. Again, just like the Yamaha, it has a sharp and responsive throttle controlling the 75bhp from the lovely 645cc V-twin which is punchy, smooth and exciting with plenty of character, something which differentiates it from the Kawasaki. 

Bike Social's Mann begins the Mountain section at the Gooseneck

Swing a leg over the Suzuki, especially having ridden one of the others, and immediately it feels as low as the spec sheet tells us – the seat height is 20mm lower than both the Yamaha and Kawasaki, which makes it a cinch for the shorter or less confident rider to control. Bike Social’s Paul Taylor is 165cm (5’4”) – the same as Marc Marquez incidentally - and could easily flat foot though he found the seat a little too hard. This is because the lack of padding to reduce the seat height so if you can easily flat foot then a plusher seat should be on the shopping list.

The SV also has the longest wheelbase which helps stability, but it's sporty geometry and set-up means it's quicker steering and handles better than the Kawasaki and WK. The Suzuki is a little diamond in the handling stake, holding a line really well and easy to flick from left to right. The Dunlop Sportmax Qualifier tyres helping to stick the SV to the road.

The build quality is excellent and despite having the smallest fuel tank, at 13.8 litres, we actually managed the best economy from the SV650 at 44.3mpg. Think of that as worst case scenario too as it was spanked along the Isle of Man TT course all day long to get that figure.

Second opinion – Marc Potter 

Potter rates the SV over the other three

I fell in love with the SV’s accurate handling and revvy, yet punchy motor when I rode it at the launch in Spain earlier this year. And I’m pleased to say I still feel the same about it when I rode it around the Isle of Man TT course. That engine offers a great soundtrack with plenty of mid-range that matches the Yamaha, but more top-end pull. It’s the sportiest bike of the bunch by far too and the chassis lets you rip round the mountain course. Quick steering but stable too with an indicated 128mph up the Mountain Mile. Yet the Suzuki offers an incredible 44mpg even when being thrashed round the Mountain course in the hands of hooligans. This bike suffered from an odd front brake which gave good initial bite but then lost power, none of the others I’ve ridden felt the same so can only put it down to a problem with the pads, maybe. Suzuki are aware and looking into it, but as I say it was a problem with this particular bike, others have been fine.

Oh, and the seat is hard, but for a mini sports bike it’s something I’d learn to live with and the bike I’d most want out of these four.

CF MOTO/WK 650i – £3299 (+ £400 pipe)

WK are the UK distributors of the CFMoto 650i and they first competed at the Isle of Man TT in 2014. 2-time TT winner Gary Johnson was fastest through practice last year and set off with the number 1 plate but retired on the first lap so the pedigree to build and run a race bike is showing itself. This year, the team return with Johnson as well as a second bike for rising road racing star, Craig Neve for the Bennetts Lightweight TT race on Wednesday evening.

The bike we borrowed for the test carried a non-standard, zebra-effect, Gary Johnson race-replica paint job with fluro wheels. Hmmm. It was also fitted with a lairy Scorpion end can (at £400 above the £3299 price tag) which no doubt annoyed the residents of Bray Hill who were enjoying the relative pre-TT peace as we popped, gurgled and cracked passed. 

Up close it’s clear to see why he CF/WK machine represents a £2000+ saving over the over three. The build quality of the Chinese import is evident with its unrefined looks including squared-off fork ends, clumsy top yoke, nasty-looking brackets, old school instrument panel and the fact there’s a manual switch for the headlights – not the norm these days.

Paul Taylor navigates around Glen Helen on the WK650i

The bike feels solid to ride with heavy steering which can be a good thing depending on your needs – it’s certainly heavy, and at 220kg this light/middle weight is only 10kg shy of an Africa Twin. With that kind of weight affecting its handling the bike was a tougher to turn at low speeds and while the suspension is cheap the bike felt firm enough for decent road holding at speed, an opinion promoted enthusiastically by Milky.

Its engine, suspension, exhaust and chassis layout is almost identical to the Kawasaki’s, on which it is based, yet it still manages to be an almost unbelievable 16kg heavier than the ER6n.

In terms of performance, the WK is not slow. Even though it’s a heavy thing and on paper has the same power as the Kawasaki, the Scorpion exhaust gives it an extra couple of bhp to reel in its rivals on the mountain sprint. The throttle action is long and languid while there’s a tendency to want to cover the clutch lever just in case the engine lets go! The 650 twin needs working, the higher the revs the more responsive the bike is and the gearbox is actually very good; smooth, direct and quick enough to be the best of the four.

Continental ContiRoadAttack 2 are the factory-fitted rubber which are a fine choice that will perform in all weather and get you to the shops and back plenty of times. The other colour choices are much more tasteful; matt black, white/black and black/orange.

Second opinion – Marc Potter

Through Waterworks and heading up to the Gooseneck for Milky on the WK650I

I really didn’t want to ride this bike. it’s based on a Chinese copy of Kawasaki’s ER6-f with styling and finish from the eighties, crossed with a bit of Suzuki B-King. The finish on most of it is terrible at best and there’s a safety chain hanging from the radiator cap that I wouldn’t hang my car keys off. But, to ride it’s actually alright. The engine is a rip-off of the Kawasaki ER6-f and has plenty of go, and thanks to the race pipe fitted to our bike, better mid-range than the Kawasaki itself. The suspension feels cheap, but it’s firm and works fine, and the gearbox is sweet too. At this price the WK is great value on paper, though I’d prefer to spend £3300 on a second hand Kawasaki ER6-f/SV650/Gladius that you know will definitely hold together.

KAWASAKI ER-6n - £5799

The Kawasaki ER-6n is by far the most popular bike on the grid in terms of Lightweight TT race entries having had its riders dominating the podium over the last four years with its riders finishing first and second in every race.

Nice and steady at speed, the Kawasaki feels well put together too with a strong parallel twin that needs working to make it really dance. Fine, the bike will cruise along smoothly in fifth or sixth, sub-6,000rpm (red line is at 11,000rpm) with ease and fluidity but the more revs the better seems if it’s to perform. It soaks them up and shows its class more so at higher speed with decent agility. That’s because at low or no speed its 204kg against the MT-07s slimline 182kg, makes for more cumbersome manoeuvring for the newer or less experienced rider. Not to say that it’s a terribly heavy bike but the ER-6n was hasn’t had a refresh since 2012 and its beginning to show its age when pitched against the brand new Suzuki and the very recent Yamaha.

The best bike for a pillion - Kawasaki ER-6n

Like a Ford Focus, it’s a competent, dependable machine ideal for new, inexperienced or unconfident riders, doing everything to a good enough standard but without excelling in any one area. It also happens to be the most expensive of the four, just.

That said, it it the only one of the four best equipped as standard for a pillion. The seat has grab rails running the length of the passenger section while the seat is adequately pitched toward the rider offering confidence to the pillion. The two-piece seat is plush and comfortable on the cheeks while being 805mm high, it matches the Yamaha as the tallest from the ground. Yet the riding position is a little sportier thanks to its slightly higher foot pegs, though all-round it's the comfiest bike of the lot.

The Yamaha and Suzuki have a character while the Kawasaki feels a little, well, beige just like its colour scheme.

Kawasaki put Dunlop Sportmax D214 tyre as OEM and they happen to be the most expensive of the group. They serve a good purpose and a are good fit for the sportier nature of the ER-6n and will equally last and wear well enough.

Second opinion – Marc Potter

Potter on the Kwaker at Glen Helen on the Isle of Man TT Mountain Course

The Kawasaki is the bike everyone uses when it comes to squeezing 100bhp out of a race-spec Lightweight TT motor, and on the road you can see why. It’s the safest of the bunch in terms of styling and that awful beige paint scheme, but as a package the Kawasaki is still a sweet bike. It’s revvier than the rest, feeling like it makes most of its power at the higher end of the revs, but in town it’s as friendly as any Honda commuter bike. The chassis works well when you start to push it too, but the bike is just starting to feel its age. As a mini-tourer or commuter it’s ace though.


It’s a two-two draw between the Yamaha MT-07 and Suzuki’s new SV650 with Milky and Potski opting for the Suzuki where as Paul and I would choose the Yamaha. All four have their benefits be they cost, performance, comfort, economy or agility, and the result was close. 

The WK is a very cost effective alternative but lacks build quality. The Kawasaki is a good all-rounder, pillion-friendly, multi-purpose wagon while the Suzuki and Yamaha feel so much newer and refined. Strong engines, agility and plenty of character is where these two excel. All are A2-compliant and will offer plenty more miles per gallon than we achieved – in fact consider our test figures the minimum economy these four will offer. But let's face it, with 90 per cent of the Bennetts Lightweight TT grid riding Kawasakis you'd have to be hard-pushed to bet against one winning later this week.

The Bennetts Lightweight TT race is on Wednesday June 8, we'll bring you the inside line on the race on Bike Social



Yamaha MT-07 in detail


Suzuki SV650 in detail


Kawasaki ER-6n in detail

WK 650i

WK650i in detail



Suzuki SV650

Yamaha MT-07 ABS


Kawasaki ER6n


4-stroke, liquid-cooled, DOHC, V-Twin

4-stroke, liquid-cooled, DOHC, 4-valves, parallel twin


4-stroke, liquid-cooled, DOHC, 8 Valve, parallel twin


4-stroke, liquid-cooled, parallel twin








Max. Power

75 bhp @ 8500rpm

74 bhp @ 9000rpm

69.7 bhp @ 8500rpm

71 bhp @ 8500rpm

Max. Torque

47 ft-lbs @ 8100rpm

50 ft-lbs @ 6500rpm

46 ft-lbs @ 7000rpm

47 ft-lbs @ 7000 rpm



Front: Telescopic forks, 41.0 mm inner tube, 125 mm travel

Rear:Pre-load adjustable rear shock , 63mm stroke

Front: telescopic forks, 130mm travel

Rear: Swingarm (Link type suspension), 130mm travel

Front : 41mm KYB/Kayaba telescopic fork

Rear: Extruded steel swingarm with tubular bracing and KYB/Kayaba cantilever monoshock

Front: 41 mm telescopic fork, 125mm travel

Rear: Offset laydown single-shock with adjustable preload, 130mm travel


Front: Hydraulic 290mm double discs, two-piston calipers, option of Nissin ABS.


Rear: Hydraulic single disc

Front: Hydraulic 282 mm dual disc


Rear: 245mm Hydraulic single disc


Front: 2 x 300mm steel discs -twin piston calipers


Rear: 225mm single disc- single piston caliper


Front: Dual semi-floating 300 mm petal discs Caliper: Dual piston


Rear: Single 220mm petal disc with single piston caliper


Front: 120/70 x 17

Rear: 160/60 x 17

Front: 120/70 ZR 17M/C(58W) (Tubeless)

Rear: 180/55 ZR 17M/C(73W) (Tubeless)


Front: 120/70ZR17 CST radial on 3.50in cast aluminium wheel

Rear: 160/60ZR17 CST radial on 4.50in cast aluminium wheel

Front: 120/70ZR17M/C (58W)

Rear: 160/60ZR17M/C (69W)



L: 2140mm

W: 760mm

H: 1090mm

L: 2085m

W: 745mm

H: 1090mm


L: 2110mm

W: 770mm

H: 1110mm

Seat Height





Wheel Base





Weight (wet)





Fuel Tank

13.8 litres

14 litres

17.5 litres

16 litres

MPG on test








£3299 (+ £400 pipe)


Suzuki and Yamaha heading to Guthries Memorial the wrong way around the TT course WK and Kawasaki neck-a-neck around Guthries on the Mountain climb Team Bike Social being social with TT-winner Milky Quayle.


Michael Mann

Jacket & Trousers: Richa TG2 jacket and Richa TG1 trousers

Boots: Dainese Torque D1 Out

Gloves: Dainese Druid D1 Long

Helmet: AGV Pista GP

Marc Potter

2-piece Suit: AlpineStars

Boots: AlpineStars Supertech R

Gloves: AlpineStars GP Pro

Helmet: Shoei X-Spirit 2

Paul Taylor

Helmet: Shoei GT-Air