Incredibly, it’s now a decade since the final PX rolled down the Piaggio production line. As time goes by we’re finding that more and more parts are being dropped from Piaggio’s stock list, and finding quality substitutes presents challenges for us as suppliers and you as riders. Although we’re well known for supplying Vespa parts, a less well known fact is that we also commission many components, ensuring that the quality is as good, if not better than the originals. Sometimes that involves using our international network of contacts to track down the Original Equipment Manufacturer who supplied Piaggio and asking them to dust off their tooling, in other cases it involves finding a reliable manufacturer who can reverse engineer the process. In the latter case we look at maintaining an original appearance, but will also take advice on improving the product. Finally, if we can, we try to support British manufacturing and that’s how our range of PX Disc hydraulic hoses came into being.
Original’s not always best
It should come as no shock to anyone that Piaggio exists to make a profit, and as a consequence every component they use is a compromise between functionality and cost. The Disc’s hose is a really good example of this. It does the job it was designed to do, namely stop a standard scooter in a safe fashion, perfectly well. However, the fastenings are made of aluminium or ferrous metals (which corrode) and the hose itself is quite flexible- meaning a loss in the potential maximum efficiency. Finally, being able to route it through the headset at the speed required by a production line meant a major compromise in its design, namely a 90 degree bend.
It’s been a long time since we had any Piaggio or OEM pipes in stock, and the most recent examples had risen in price considerably. We thought it was time to produce our own solution, and that’s where HEL Engineering comes into the picture.
Proudly made in Devon
All HEL’s metal motorcycle components are manufactured at their Devon factory from a carefully selected mix of materials. The hose is bought in from a manufacturer in the UK and their stainless steel bars are obtained from Amodil in Worcester from their mill in Spain. Aluminium billets are bought from Smiths Metals from their Redruth branch to minimise transportation miles.
Additionally, all HEL’s stainless steel brake line fittings, aluminium master cylinders, callipers, thumb brakes and finger brakes are all made at HEL HQ on their own fleet of Star CNC and Brother CNC machines.
What impressed us most about HEL was that they only use stainless steel and titanium, and that the pipes are supplied fully swaged. This combination means that not only do their pipes last longer, they also perform more efficiently. There’s an added benefit in that the PVC coating used to protect the pipe comes in a range of colours, which gives even more options to customise your ride.
Change for the better
When discussing how we could best design a replacement hose the issue of the 90 degree bend came up fairly quickly. As a general rule, 90-degree bends are considered bad or undesirable in high-performance hydraulic systems. They introduce ‘minor losses’ in flow which lead to significant pressure drops, increased turbulence, and reduced flow efficiency. In fairness, these aren’t to the degree that would be noticeable on a standard PX, but on a kitted machine with a high-performance brake set up, every degree of efficiency is important.
There were good reasons for Piaggio to adopt this on the production line, we felt that performance was more important to our customers than the speed of fitting and agreed with HEL that we should soften that angle. A critical condition of this decision was that it would fit inside the headset without any need for drilling or cutting. Wev’e pleased to say that after lots of experimentation that’s something we’ve achieved, but it does mean the HEL line looks different than the OEM component. So, to clear up any questions about fitting here’s our handy guide.
Perfect fit
Obviously the headset top needs to be removed but fitting the hose is much easier with the headset lifted above the steering column, which allows much more room to manoeuvre the pipe in the narrow confines of the neck area. Thread the pipe from the bottom and up through the neck, then loosen, or preferably remove the master cylinder. This will make aligning the top threaded fitting much easier.
With the fitting inserted finger tight, reattach the master cylinder. Now, the difference in OEM and HEL pipes becomes clear. Whilst the OEM pipe sat above the throttle tube, the HEL pipe now runs above the throttle wheel. Don’t worry, although no one’s going to describe the area under a PX headset as spacious, there’s far more room that might be expected. As the throttle wheel only rotates through a limited arc, there’s plenty of space to run the pipe over it without snagging.
Our suggestion is to rest the fitting on top of the lug that guides the headset top and then try dry fitting the headset. You may find that a couple of very minor adjustments are needed before the headset sits snugly, but it will! The trick is to be patient and make any adjustments in small increments.
Once the headset top is sitting perfectly, the fastening can be fully tightened.
The next question we get asked is what are the two silicone ‘bobbins’ for?
These fit into the mudguard clamp and the hose fastening strap that’s located under the horncast. The ‘bobbins’ allow the hose to be secured firmly in place without constricting the internal diameter of the pipe.
Once that’s done, it’s simply a question of routing the pipe through the mudguard, connecting to the calliper using the banjo bolt and copper washers supplied with the kit and bleed as normal.
Simple? Certainly, but just as with all of the products we commission a lot of time and effort’s been spent to make sure this simple solution is the best we can achieve.
For more information, or to discuss bulk orders contact our sales team on 01226 203377
