When the 310 GTS/GTV was unveiled at the 2024 EICMA motorcycle show in Milan, it confirmed the worst kept secret of modern scootering; Vespa was going large. With its 310cc HPE power unit, this iteration of the GTS family has become the largest capacity, most powerful Vespa ever to leave the factory at Pontedera. Understandably, owners of previous machines are keen to understand what benefits this brings in the real world and whether they should trade up. In the first instalment of a two-part blog we’re going to try and answer those questions. To do so we enlisted the help of Scootering Magazine’s editor Dan Clare, who provided the dyno facilities, and the magazine’s former editor, Stan, who took our demonstrator out for a test ride.
The science part
To answer the question of how the 310 compares to previous models we selected two machines that were well known to us, a Quasar engined 300 and a HPE 300. Both of which Dan ran against our 310.
Before going into the results it's worth pointing out that our dyno figures differ from those provided by Piaggio. This isn’t because of any ‘creativity’ on Piaggio’s part; manufacturers generally quote power generated at the crank, which is a great indication of engine power. Our tests measure power delivered at the rear wheel, which is always lower because of friction in the drive train. The dyno measurement is more relevant to riders in the ‘real world’ but both measures are valid, so long as they aren’t mixed up. There are also problems in measuring torque delivered through a CVT (auto) transmission on the type of dyno used in this test, so we’ve stuck to Piaggio’s figures for that. Right, on with the show…
Quasar 300
Expectations were high at EICMA 2007, when Piaggio announced that the 250cc Quasar engine fitted to the Vespa GT models had been stroked out from 244 to 278cc. In reality, the new 'GTS' was something of a disappointment. Quoted power remained the same at 22Bhp, although the 300 produced it 750rpm lower down the rev range than its smaller capacity sibling, a fact reflected in the improved torque figures which rose from 19.2 Nm @6,500 rpm to 22.3Nm @5,000rpm. Unfortunately, some handling problems remained, notably the distinctive low speed handlebar shake. Although the Quasar 300 remained in production until the HPE arrived, many enthusiasts preferred the 250, which explains why good survivors of the lower capacity machine are still keenly sought after.
It’s worth noting that Piaggio has recently deleted drive belts for the Quasar from its spares inventory, meaning that aftermarket replacements are the only option. For news on a quality replacement, watch this space…
The 2018 scooter we used for the dyno run was purchased from us brand new by Simon, who rode it as a commuter until selling it a few weeks ago. In his care this GTS has covered a little over 4,500 miles and has been fastidiously maintained by our workshop team. Other than a small scrape on one panel, it’s almost as new and proves the value of proper servicing.
On the dyno the Quasar produced a maximum of 17.09 bhp, topping out at an indicated speed of 89mph- which we all know is purely theoretical!
HPE/RST 300
Although it was unveiled at the 2018 EICMA show, it was February of 2019 before the motorcycle press was invited to sample the delights of Piaggio’s ‘High Power Engine’. Although the capacity of 278cc was unchanged; with a reworked head, fresh injector and completely revised transmission it promised great things, and this time Piaggio’s engineers delivered. Quoted power rose to 23.8BHP @8,250rpm whilst torque also increased to 26Nm @5,250 rpm.
Reviews from the press were overwhelmingly favourable, with one exception; the rev limiter was set unnecessarily low. Despite the improved performance, top speed was less than the Quasar models with the limiter kicking in at an indicated 83 mph. In real life this was somewhere in the low 70mph range, and riders soon discovered that opening the throttle to overtake on motorways became a high adrenaline sport. Fortunately, a solution was at hand in the form of a ‘speed ring’, which replaced the existing rear wheel sensor, recalibrated the speedo and put the HPE’s top end speed back in line with its predecessor. This is probably the most cost effective piece of tuning equipment ever produced in the world of scooters- two or four stroke! The HPE also saw a massive improvement in handling, with many of the historic problems such as low speed wobble being eliminated.
It’s fair to say that the RST’s arrival came as something of a surprise to the industry as a whole. However, we now know that its improved suspension, revised frame and streamlined styling were in preparation for the 310’s arrival. This makes the RST something of a ‘crossover’ model, incorporating the proven HPE 300 unit with the 310 chassis.
The machine we used is another scooter supplied by us from new and is one of the last pre-RST models. This was carefully maintained in our workshops until, with 7,500 miles on the clock, we took it in part exchange when the owner traded up to an RST. It's a perfect example of the type of used machine we like to offer in our showroom and was snapped up by Scootering Magazine for use in its ‘auto-tech’ series. The dyno reading used here is the one taken on arrival at Dan’s workshop, before the various upgrades that have been detailed in the magazine were made.
On our dyno run the HPE produced a maximum of 20bhp, whilst the limiter’s effects on top speed can be clearly seen.
Leader of the pack: GTS 310
Will Piaggio ever produce a larger capacity scooter than the 310? Who knows, but from the outset we should say that the 310 wasn’t created to satisfy the desire of scooterists for a bigger, faster machine. In fact those, undeniable, improvements are merely a benefit of developing an engine that can continue to deliver large capacity scooter performance whilst complying with increasingly difficult emission laws.
Had Piaggio simply wanted to create a larger capacity motor, they could have achieved that in a fairly straightforward fashion by stroking out the HPE. Instead they’ve gone way past simply stroking out the engine; there’s a new SOHC roller-cam timing system with optimised valve lift, the cylinder has been offset, a new multi-jet injection system has been developed and the crankcase has been completely revised. This new crankcase is claimed to reduce belt noise and houses an entirely new drive train. Starting is also claimed to be easier thanks to a new improved starter motor. Having left no stones unturned, this looks like an effort by Piaggio’s engineers to future proof the motor, giving them a little wiggle room when the next round of emissions regulations arrive.
At the factory, Piaggio claim 25bhp @6,500rpm, an improvement around 5%, but at much lower revs. In terms of torque the 310 sees that rise to 28.9Nm @5,250, an improvement of 10%.
For the dyno runs, we loaned Dan our own demonstrator; a scooter that you too can take out to test ride by contacting our sales team on 01226 203377. This is a scooter that’s very much fresh out of the box, in fact at the time of this test it had only covered 150 miles, so there’s plenty time for the engine to loosen up a little.
On the dyno, our 310 produced 22.03bhp, which suggests that Piaggio has been very cautious in its performance claims. Rather than the 5% gain over the HPE quoted by Pontedera, on our dyno the improvement is closer to 9.5%. Unfortunately, the rev limiter remains and this time it screams, "Stop trying to hurt me" at an indicated 87.71 mph.
So what do our dyno runs prove? Well, the 310 has an incredible 25% increase in power over the first generation Quasar machines and 10% over the HPE; proof that Pontedera’s engineers are never content to rest on their laurels.
The next question of course is how does that translate into real world riding? You’ll have to wait for part two of this blog to find out...
Images courtesy of Stan/Scootering Magazine
