Deep dive, Sintesi 88 - type EH

More than any other generation, the 1988 Sintesi AF1 125 was a huge jump forward and offered the 125cc class features rarely seen on superbikes let alone on learner legal motorcycles. At the time it was compared to the mighty Honda RC30 superbike racer for the road, which is high praise indeed, but again this was a 125cc motorcycle you could ride at 17 (UK) making it even more remarkable.

The updates over the previous Project 108 model were considerable with the new bike featuring all-new bodywork including twin round front headlights, GP inspired radiator openings on the fairing, separate seats for the rider and pillion, with the pillion seat colour coded to give the elusion of a single seat unit. The metal fuel tank hinged upwards to gain access to the spark plug, battery and coolant reservoir. The stock Sintesi gained bold new graphics with a purple colour band which were very much in-tune with the younger generation of the era. For the UK (and export) market we gained the classic Reggiani Replica with striking graphics and the number 6 proudly displayed on the tail piece. This bike featured heavily in the UK media and helped put Aprilia firmly on the map.

Chassis updates include:
All new twin-spar aluminum frame - significantly lighter and stiffer over the steal frame it replaced.
Alloy 'rear set' foot rests for the rider and pillion.
38mm upside-down fork - 4 years ahead of the Japanese
Single-sided swingarm and APS suspension - carry over part from the project 108
New 17" multi spoke wheels - sizes: 100/80-17 front and 130/70-17 rear
New 320mm floating front disc brake with a four-piston calliper

Engine updates include:
The new Rotax 123 replaces its predecessor, the 127, and remains a mainstay of the Aprilia range up until 1994, when it was replaced by the Rotax 122. Here are the most important new features:

New aluminum cylinder with Gilnisil-treated liner
New two-piece cylinder head for improved cooling.
Stroke 54 x 54.5
Compression ratio dropped to 15:1 (15.5:1 on the Replica).
Balancer shaft (not present on the Rotax 127).
Dell’Orto PHBH 28 RD oval-section carburettor.
Rave 2 pneumatic power valve
New airbox with dynamic air intake mounted on the right side of the bike.
Maximum power output of 28.66hp at 10,500 rpm

A, B and C versions
In early production the fuel cap is located on the right hand side of the fuel tank and without the breather hose, with the vent integrated in to the fuel cap. These early models can be identified by the codes "A" and "B" which are visible on a decal on the seat subframe.

All subsequent production bikes have identification code "C," on this version the fuel cap moved to the left side with an additional external vent on the right.

Left side, AB fuel tank, right side C fuel tank

Colours

Black, purple, white and red

Dark blue, aquamarine, white and red

Replica

There is a forth colour that appeared in a bike listings catalogue which I am not 100% clear if this was a pre-production colour that got dropped for another option, a low production colour (I have not seen another one?)or even a colour mishap in the print process!

Black, green, white and red

Pre-production Project 108 AF1 Replica

Here is a great picture from the 1987 Milan motorcycle show showing the Replica version of the AF1 Project 108. As you can see the bike has slightly different colours with red on the tank and more green on the side panel and a green number spot on the tail, but the biggest change is that it also features a single headlight. 

It is common for manufacturers to display non-production ready machines or display machines in differing colours to test the market, or maybe the headlight fairing just wasn't ready in time for the show? I have also heard that twin headlights only became legal in Italy in 88, so maybe aprilia updated the bike to take advantage of this, but that needs fact checking. Either way its another piece of the model time-line.

image 1987 Milan Motorcycle Show

production version of the AF1 Replica

The 1989 AF1 Reggiani Replica

Did Aprilia release any production Type EU Sintesi bikes with a number 6 on the tail piece (Reggiani) or were all bikes number 4’s (De Radigues)?

On Aprilia's own workshop manual it features the Sintesi version 1 (type EH) and the version 2 (type EU), on closer inspection the type EU features a number 6 on the tail unit like the type EH Reggiani relplica.

Image from the official Aprillia workshop manual

Digging a little deeper the number change happened to reflect the changing of Aprilia's sponsored GP riders and the need to sell was being raced at the time.

Making its debut at the 1988 Bologna Motor Show, Aprilia presented the updated type EU Sintesi Replica 125 motorcycle featuring the number 6 on the seat unit, this was to reflect their then sponsored rider Loris Reggiani who ran that number in 1988 season. However, after finishing 13th in the 88 season Aprilia did not renew the teams contract and the rider switched to Honda. For the 89 season Aprilia replaced Reggiani with the Belgian Didier De Radigues. As the new rider came from the 500cc class to the 250cc class he did not have a race number frpm the previous season so was assigned the race number 4. To reflect their new rider Aprilia changed the tail number from 6 to 4 on the Replica model for production versions, however some bikes were sold as Reggiani '6' bikes in the first few months of 1989 but are extremely rare.

This would also explain why the De Radigues Replica bikes are technically in the 88 Reggiani colours rather than the revised 89 colours as at this point the bikes were probably already made or at the minimum some body panels would of been painted ready for assembly. 

1988 Reggiani race bike

1989 De Radigues race bike

If you have a genuine number 6 type EU please leave a message bellow as I would love to see it!

Many thanks to the contributors of the Aprilia AF1 page on facebook and  125 Stadali

UPDATE 06/11/2023

Taken from Practical Sportsbike magazine July 2016

number 6!

image captured from a video at the 1988 motor show

Brochure, 1988 AF1 Sintesi Replica

*** this brochure showed the bike with a red Aprilia decal and an Elf sticker, production bikes had white lettering for the Aprilia decal and a Mobil 1 decal. Here is my photoshopped version to correct the image to actual spec.

AF1 - model history

 AF1 or 'Aprilia Formula 1' is a series of small capacity motorcycles from (at the time) a small Italian motorcycle manufacture Aprilia that seemingly came out of nowhere in the late 80's and in to the 90's. 

The 125 category in the UK was fairly stagnant for years with the mainstream Japanese only rally offering colour updates on long running machines. We had the Honda NS125F which was made in Italy and featured a larger chassis, but Kawasaki's AR125, Suzuki's RG125 (actually based on a RG80) were tiny. Yamaha updated the ageing RD125 with the more modern TZR125 but even this was skinny. All of these bikes had similar performance as in the UK all learner 125's had to be restricted to 12hp giving a maximum speed of around 70-75mph.

Meanwhile in Europe and in particular Italy 125's were about to turn in to serious motorcycles with almost 30bhp and reaching speeds of up to 100mph! 

Aprilia first showed there intentions by showing a prototype AF1 125 at the Milan motor show in 1985 and although styling was maybe influenced by the Japanese it was light years ahead of anything else.

1985 AF1 125 prototype

 In 1986 Aprilia release the AF1 50 making the 50cc version the first production AF1.

1986 AF1 50

1987 - AF1 Project 108 Type AC/1

The production version of the AF1 125 made its debut in 1987 and was called the 'Project 108'. The biggest change over the prototype was the addition of a single sided swing arm. The Aprilia name for the swing arm was 'Project 108', hence the model name. This was a technical first for a production bike on sale in Europe, although Honda did have it on the VFR400 NC24 in Japan. It also featured a steel box section frame, 3 spoke 17" wheels (16" on the prototype), anti dive forks and RAVE power valve on the Rotax 127 engine.

1987 AF1 Project 108, white, black

1987 AF1 Project 108, blue with white panel

With new rivals hitting the market in the form of the Cagiva Freccia C9, Gilera ZK and the Honda NS Aprilia made a quick update with a twin headlight fairing.

1988 - AF1 Project 108 Type AC/1

With a striking paint scheme inspired by the 250 gp race bike if Loris Reggiani or the first time the 'Replica' is offered. For the Second colour Aprilia really embraced the era using contrasting colours, something they will embrace of the next few years.

1988 AF1 Project 108 Loris Reggiani Replica

1988 AF1 Project 108, white, black, red 

1988 - AF1 Sintesi Type EH

First shown in June 88 the all new AF1 Sintesi changed the game more so than any other generation. With more than a passing resemblance to Honda's RC30 the Sintesi featured the new Rotax 123 engine with RAVE 2 power valve, aluminium beam frame, 38mm upside down forks, single sided swingarm with new muli-spoke wheels. Colour options are black, purple, white, red or blue, aqua, white, red

1988 AF1 Sintesi, black, purple, white, red

1988 AF1 Sintesi, blue, aqua, white

For the export markets like the UK a Replica was also produced, this is another Reggiani replica with a number 6 on the tail piece.

1988 AF1 Sintesi Replica

1989 - AF1 Sintesi Type EU

In keeping with Aprilia's mid-model updates the Sintesi was updated for 1989 and featured a new top fairing with smaller headlights, new 'AF1' alloy top yoke, new clocks (loosing the fuel gauge) and a new 'aircraft' style fuel filler cap. This model was offered in the Sintesi colour scheme and the Replica. The Replica now had the number 4 on the tail piece reflecting Aprilia's current GP rider of the time Didier De Radigues.

1989 AF1 Sintesi

1989 AF1 Sintesi Replica

1989 Sintesi Sport Type FG

The final Sintesi was called the Sport and was produced for the Italian Sport Production Championship using a 34mm carb opposed to the 28mm carb from the previous version. This gave a decent power increase but as it was sold alongside the new Futura sales were not that strong.

1989 Sintesi Sport

1990 AF1 Futura Type FM

Aprilia launch the Futura as successor to the Sintesi in Feb 1990, although its looks like a big redesign in reality it has minor updates to the chassis and engine and keeps the 34mm carb from the Sport. The new fairing features a flush single headlight but for the UK market twin headlights were used. 

1990 AF1 Futura

UK version with twin headlights

1990 AF1 Europa Type PV

Launched shortly after the Futura was a naked roadster version called the Europa. The Europa was produced to appeal to riders that didn't want a race replica and competed with the new NSR-F but with lower gear ratio's it actually accelerated quicker than its faired stable mates. Made in both 1990-91 without change.

1990 AF1 Europa, Metallic amaranth

1990 AF1 Europa, Metallic electric blue

1991 AF1 Futura Type GE & GR

Another mid-life update for the Futura, this time with a modified seat unit rather then the headlights. Offered in both a stock colour scheme and the return of the Reggiani Replica.

1991 AF1 Futura - Type GE - show bike with original Futura bodywork

1991 AF1 Futura - Type GE - production

1991 AF1 Futura Reggiani Replica - Type GR

1992 AF1 Futura Sport Pro Type HC & FM

Although from a technical point of view the Sport Pro is identical to the Futura '91, there are a few detailed updates including a new control unit for the exhaust valve control that opens at 8400 rpm. (7800 rpm on the other Futuras), a new exhaust can in aluminum with a carbon wrap and a 28mm carb, (which was needed for racing), an adjustable rear shock absorber and a wider 140/70 rear tyre.

Type HC were the original Sport Production bikes (772pcs), Type FM are in fact 91 Futura's in Sport Pro colours (2228pcs). For the road the FM is faster due to the 34mm carb.

1992 AF1 Futura Sport Pro

92 Sport Pro UK version, note twin headlights

After the Sport Pro Aprilia had a wholesale redesign and dropped the single sided swignarm for a double sided with the RS 125 which continued on sale in various forms until the two stroke engine effectively got outlawed by emissions. 

For a deep dive in to the model history and also a look at the AF1's main rivals take a look at https://125stradali.com/en/aprilia-125-stradali-aprilia/

Magazine, AF1 Family Tree - Practice Sportsbikes