DBR test pilot Ryan Houghton gets loose as a goose with Yamaha’s pair of MX four-poppers…
Yamaha have been picking up plenty of silverware in recent seasons and the Grand Prix and US motocross teams have certainly made the most of the excellent basic package and superb pilots at their disposal. Names like Guillod, Lieber, Barcia and Van Horebeek have improved their championship results while riding blue and Romain Febvre, Jeremy Martin and Cooper Webb have brought home the biggest prizes of all on the World and American stages. Yamaha clearly live by the ‘if it ain’t broke don’t fix it’ philosophy and their ‘new’ 2017 YZ model range reflects their belief that they already have a winning formula in their motorcycles.
Revision rather than radicalisation is the order of the day as I scoot off to Italy to find out what the 2017 Yamaha range is all about. The test was conducted at a place called Dornoland in Italy. I’d never heard of it before but it was one of the best tracks I’ve ever ridden for sure. It’s only a practice track but it was prepared to perfection, watered after every session. To be honest I’m getting spoilt on these tests!
YZ250F
We’ll start with the YZ250F and it really is a lovely bike to ride. It’s not necessarily the prettiest thing in the world – a bit of a lump really – because it has those massive rad scoops and air box on the front. In fairness when you get out there and ride the Yam they don’t feel as big as they look even though I still think they could shift a few pounds but couldn’t we all.
Yamaha say that their new 250 ‘crosser’ benefits from a range of important technical changes – such as an all-new reverse cylinder head – that are aimed at delivering increased performance and enhanced rideability. Yamaha have aimed to improve the acceleration and pulling power in the mid-to-high rev range and they have done this by gearing all their engine changes around efficiency. They have made stronger valve springs and a new con-rod to cope with the increased engine performance, redesigned the exhaust port and brought in a new big bore front pipe to achieve optimal intake/exhaust balance.
While it’s clear that Yamaha have been working hard on improving the mid to top power on the 250 I didn’t feel as though it had enough grunt at the top end – it just seems to stop pulling just as you need it which is a shame. On the other hand I have to say the 250F has one of the best bottom to mid power ranges I’ve experienced in a while. It has amazing bottom end power and pick up out of the corners is excellent.
Other than that top end issue there are loads of other things I like about the Yam. A new remapped ECU with revised ignition timing is mega. Basically the ECU cuts in at high rpm and features a rev limiter that gives improved over-rev feeling. Braaaaap!
Ergonomically, Yamaha have dropped the footpegs by 5mm like they did on the 2016 450F and it makes the bike extremely nimble and easy to turn. I felt myself being able to push the front end hard into corners and then transition the control to the rear extremely easily. The brakes are pretty sharp this year after the 245mm rear disc gets the same heat resistant steel as the as the front 270mm stopper. I was also impressed at how easy the 250 is to start as like a spanner brain I stalled it in one session. She was hot as hell but started first kick…now that is handy!
Another improvement I noticed was Yam have changed the clips holding on the airbox/rad scoops. It’s a good job they have because it was so easy to knock the two bolts off the side when you were riding, and you ended up with just one holding it on. If I was a looking to buy a good solid machine as an amateur rider then I would defo recommend the 250F because it is so easy to ride.
YZF450F
For those of expecting a brand new bike you might be disappointed but for people like me who really enjoyed the 2016 MX1 bike then never fear.
The bike is very much the same as last year with a few minor improvements. Yamaha have given the 450 a new rear brake because the 2016 was prone to fading. I’m very heavy on rear brakes normally so I have to run a factory Brembo on my race bike but I didn’t feel any fade at all in the new 2017 Yams so all good there.
As usual the power of the Yam is serious. It is so bloody fast and I feel this works really well on a nice big open fast flowing track. But I think that in the tight corners when you are getting on the gas you may find yourself playing with the clutch trying to keep that front end down and tame that power!
I would say if you buy the 450 make sure you get the mapping dialled in for you. The key here is that it’s so easy to use the Yamaha power tuner. The tuner can be used without the need of a laptop and if you go on their website they have all sorts of maps you can copy onto your bike. Personally I would mellow down and spread the power out just making it easier on your arms and shoulders.
I really like the suspension on the new models. All I did was set the sag and I was away – the stuff is pretty plush. So if it’s the correct spring for you then it will be pretty good.
Technical Specifications: YZ250F
Displacement: 250cc
Bore and stroke: 77 x 53.6mm
Transmission: 5 gears
Fuel system: Fuel Injection
Front suspension: KYB AOS forks
Rear suspension: KYB shock
Suspension travel front/rear: 310/315mm
Front/rear brakes: Disc brake 270/245mm
Wheel base: 1475mm
Ground clearance: 330mm
Seat height: 965mm
Fuel capacity: 7.5 litres
Weight: 105kg
Technical Specifications: YZ250F
Displacement: 449cc
Bore and stroke: 97 x 60.8mm
Transmission: 5 gears
Fuel system: Fuel Injection
Front suspension: KYB AOS forks
Rear suspension: KYB shock
Suspension travel front/rear: 310/315mm
Front/rear brakes: Disc brake 270/245mm
Wheel base: 1480mm
Ground clearance: 330mm
Seat height: 965mm
Fuel capacity: 7.5 litres
Weight: 112kg
