Tuesday 27 September 2016

Walk Fat Boy Walk

One of my very good friends has Chronic Myeloid Leukemia. After his diagnosis he was helped by, and was very impressed by the charity Bloodwise. On Saturday I walked from Exeter to Dawlish to raise money for them. While he sponsored me, one of my colleagues said that it didn't sound like much of a challenge, and that I should at least do it barefoot, or with a hat made out of a pineapple, or something. It was a long walk, and I now have blistered feet and a bloody bruise under a toenail. My sponsor will be pleased to know that I did have to do battle with two of nature's most fearsome foes: The sea, and a wittering old lady.

The last section of the walk was along the seawall at Dawlish. It was blowing about force 6 onshore and the waves were breaking over the wall. I didn't get swept to my death, but I finished the walk drenched head to foot with seawater.

Most of the people on the walk were lovely but going too slowly for me. (They were generally walking with some combination of children, dogs, and bloodbourne cancers). I ended up at the front and absolutely unable to avoid talking to a boring old woman. She went on and on about herself, how the walk should have been advertised, standards in journalism, standards in teaching and the decline of Exeter. I found her so irritating that whatever subject she started banging on about I would take the most opposite and offensive viewpoint that I could. Sadly she was absolutely un-wind-up-able and despite an hour's concerted effort I failed to provoke an argument.

Thank you very much to everybody who sponsored me. It really is a worthy cause.

Richard "nobody said I had to be polite or magnanimous" B

Sunday 11 September 2016

TMax Fever

The Yamaha T-MAX is susceptible to a disease where it won't restart in hot weather. Mine developed the disease and I thought that it was a battery problem. I was wrong. This is everything that I know for sure about T-MAX Fever: In essence it is "The bike will start after a few hours. Go and buy an endoscope"

(This relates to the XP500, I don't know if any of it holds true for the newer XP530)

  • If you turn the ignition on while the stop/run switch is set to run, then the fuel pump should run for 2 seconds. You can hear the relay click behind the headlamp, and you can hear the fuel pump run under the front of the saddle.
  • During a bout of T-MAX fever the relay clicks but the fuel pump doesn't run.
  • Whatever the problem is, it exists within the fuel tank. I managed to disconnect the fuel line and check that the pump was getting power - it still didn't run until the bike had cooled down for several hours.
  • The fuel pump runs all the time that the engine is running. A fuel pressure regulator valve inside the tank directs most of this fuel back into the tank, the fuel line to the injectors should be pressurised to 2.5bar.
  • The fuel tank contains a single complicated unit comprising the filter, pump, pressure regulator, fuel level sender, wiring, and connectors.
The motor is on the left next to the filter. The F.P.R is just visible on the right below the main column.
  • Yamaha calls this whole unit the "fuel pump" and they don't sell the individual components. They charge about £400 for the unit. The thieving bastards.
  • It is easy to get a replacement pump to fit into this unit.
  • It is nearly impossible to get a replacement F.P.R for this unit. Polini sells one (part number 1730001) that runs at 3.5 bar rather than 2.5 bar. It seems to have the same dimensions as a F.P.R. from an old Toyota MR2 but that has an even higher fuel pressure pressure.
  • During correct operation petrol pisses out of the F.P.R and runs back into the tank.
  • If I owned an endoscope I could have checked that this was happening by simply stuffing it into the tank through the filler - I don't.
  • On my bike the F.P.R had seized - unfortunately my attempt to "free" the valve destroyed it.
This is what I believe happened:
  1. Innumerate environmentalists persuaded everyone that petrol should be laced with ethanol.
  2. Galvanic corrosion between the different metals seized the F.P.R.
  3. The pump has been working against a solid column of fluid, labouring and cavitating and eventually overheating.
  4. The hot pump just about carries on spinning, but won't restart once it's stopped.
I have fitted a new (second hand) unit to my bike, judging by what I've read it's still from the susceptible batch. I might fit a fuel pressure take-off to the fuel line and buy a gauge but that is looking rather difficult. If the pump gets noisy, or if I have fever problems again I will rush out and buy an endoscope and observe the F.P.R. I'll keep my readers informed.

Richard "Everybody's got the Fever" B

Tuesday 6 September 2016


My favourite motorbike was a Kawasaki GT550. They fitted and suited me and their reliability was legendary. They were blessed with lazy and benign handling characteristics, they had a multi-function display that would have looked futuristic in the 80's and self-cancelling indicators with tactile feedback.

I called mine "The Old Faithful" and I rode nearly a quarter of a million miles on it. The only times that it didn't take me to where I wanted to go were when it was stolen and when it had a flat tyre. It had a shaft drive running in an oil bath so it never once asked me for a new chain and sprocket. It broke a couple of clutch cables, but I was able to start it in gear and carry on riding it with clutchless changes. About half way through its life I took the frame out and had it powder coated. It had a twin-coil lost-spark ignition system so when one of the coils went wrong I could ride it home on two cylinders. I think the worst fault was when the steering head bearings went rusty and stiff. It was almost impossible to balance but I carried on taking it to work while the bearings were on order.

Compare that to my Yamaha T-MAX which is less than 4 years old and has 22,500 miles on the clock. It has developed a serious and expensive fuel injection fault and every time it gets hot it strands me at my destination for a few hours while the (submerged) fuel pump cools down.

Richard "It's like that one girlfriend that you never really get over." B