wait Pablo let me get this straight ,Too much rain won't allow you to remove the two screws behind the seat and the filter hose
When its raining, and I have to wheel my Bikes outside to work on them, I get wet....
..and I HATE getting wet...I go all "crinkly"!...

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I've been fiddling with all my various Motor Bikes and vintage Motor Cars, over the past 62 years, so I've got used to it now...
...providing I am NOT outside when its raining!...

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Rain make me Wet and unhappy!
Paul...

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The snag with small engines with small Carburettors, is that the Jet holes/Float Valve are extremely small, and easy blocked, with any debris (and varnish build-up when left standing for some time), that passes the Petrol Filters.
This little Yamaha Bike had been standing unused for 15+ years in my house, so its Carb needed a good clean with solvent, and all the jets cleared, etc..
She is running as sweet as a nut now!...

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..but its started to bloody rain again!
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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.