How to make sure your bike isn’t a fire hazard come Spring
Cure those cracked, leaky old pipes in ten easy steps
1 Drip, drip, drip
If you’ve noticed a fuel leak from your bike chances are it’ll be from a perished pipe. As well as being a safety concern, leaking fuel will also result in an MoT failure, so you’ll need to investigate. First, completely drain the tank into a suitable container to make the job safer and easier – do this outside using a fuel syphon (these are cheap to buy and essential).
2 Free the tank
When the tank is completely drained you next need to gain access to the underside. Check the specific procedure for your machine in a workshop manual. The Honda VFR800 we are working on today first needs two bolts to be undone at the front, this allows the tank to then be lifted up rather than coming away completely as the rear is hinged.
3 Unclip connectors
Undo the electrical connectors that lead to the tank, these will be for the fuel tank level sender and the fuel pump. These types of connectors are often high-quality and properly sealed to prevent damp or water penetrating. This can often make them feel difficult to separate, so take your time and make sure any locking tabs are depressed or raised as required.
4 Take a breather
Now you need to remove the breather/overflow pipes from the tank – there will usually be two. They are responsible for venting the tank as fuel is used and also as an overflow for the tank filler. There is no need to remove them from the bike at the other end, simply move them to one side so as not to disturb the routing.
5 Pull off the pipe
There should now be only two pipes connected to the tank, one is to the injectors and the other is the return. Identify which is perished; in our case it’s the return pipe. Loosen the clip using pliers and slide it away from the injector outlet. Have a container handy to catch any fuel and gently twist and pull the pipe off. Repeat for the other end of the pipe and remove from the petrol tank.
6 Source the replacements
Never be tempted to use pattern or generic clips to tighten fuel lines. Although it might appear to be better to use a small jubilee type of fuel line clip, these often don’t sit correctly and cause the edges to cut into the pipe if overtightened. Original clips aren’t expensive, so it’s not worth cutting any corners. The same goes for the fuel line itself, always use OE where possible.
7 On the right route
Check the correct routing of the fuel lines in a workshop manual. Following the original routing is really important because if it’s done incorrectly the fuel line will get pinched and restrict fuel flow, causing running problems. At the same time check the routing for any breather pipes from the tank.
8 Is it in shape?
As mentioned in the previous step, one of the worst things to do is replace the fuel line with generic pipe. Even if you source a pattern pipe with the correct bore it often will have a different outer diameter. Original fuel lines are usually shaped to fit around the architecture of the bike – a generic pipe will not be.
9 Clip and fill
Fit the new pipe on the injector end first using the correct type of clip. Make sure that the pipe is the right way round to aid routing. Fit the pipe with a clip to the tank, and then click together the electrical connectors and breathers your removed earlier. Pour a small amount of petrol into the tank – around two litres will be fine.
10 Stop, listen, look…
Don’t fasten the tank yet, first you need to check that there are no leaks. Turn the ignition on and wait for fuel pump to initialise, you will hear it turn off once it has pressurised. At this point turn the ignition off and lift the tank up enough to shine a torch around the area where you fitted the fuel line. If there is no sign of leaks, refit the tank.