ON short trips, make sure you have the following items:

1. NGK BP(R)5HS Spark Plug with 0.5 mm gap
2. Front & Rear Bulbs
3. 0.2 uF 500V DC Condenser (or 0.22 uF 1000V DC Polypropylene Capacitor)
4. Tyre Pressure Gauge
5. 150 mm (6") Adjustable Spanner for:
• Spark Plug (21 mm)
• Wheel Nuts (17 mm)
• Seat Bolt (14 mm)
• Engine Cover Nut (13 mm)
• Engine Protector Clamp Bolt (10 mm)
• Spark Plug HT Terminal Nut (7 mm)
• Condenser Nut (7 mm)
6. Flat-Blade Screwdriver for:
• Contact Breaker fitting & adjustment
7. Cross-Head Screwdriver for:
• Rear Bulb replacement
8. Puncture Repair Kit
• Two Tyre Levers
• Two Tyre Valves
• Two Valve-Extracting Tyre Caps
• Inner Tube Repair Kit
9. Cotton Cloth

ON long trips, make sure you have the following items:

1. NGK BP(R)5HS Spark Plug with 0.5 mm gap
2. Magneto Rotor Extractor
3. Front & Rear Bulbs
4. Filters:
• Foam Air Filter
• Fuel Tank Filter
• Carburettor Fuel Filter
5. Fuel Return Pipe (Clear Tubing of 9 mm internal diameter x 105 mm long)
6. Contact Breaker
7. 0.2 uF 500V DC Condenser (or 0.22 uF 1000V DC Polypropylene Capacitor)
8. Tyre Pressure Gauge
9. Two Front Spokes (13 gauge [2.2 mm], 225 mm long)
10. Ten Rear Spokes (13 gauge [2.2 mm], 195 mm long)
11. Spoke Adjustment Tool
12. Flat-Blade Screwdriver for:
• Contact Breaker fitting & adjustment
13. Cross-Head Screwdriver for:
• Rear Bulb replacement
14. 9 mm Ring & Open-Ended Spanner for:
• 9 mm Air Filter Housing Cover Bolt
• 9 mm Main Jet
15. 10 mm Ring & Open-Ended Spanner for:
• Cylinder Nuts
• Cylinder Head Nuts
• Fuel Pipe Unions
• Carburettor Throttle Cable Assembly Bolt
16. 14 mm Ring & Open-Ended Spanner for:
• Magneto Rotor Nut
• Seat Nut
17. 15 mm Ring & Open-Ended Spanner for:
• Carburettor Manifold Union
18. 150 mm (6") Adjustable Spanner for:
• Spark Plug (21 mm)
• Wheel Nuts (17 mm)
• Seat Bolt (14 mm)
• Engine Cover Nut (13 mm)
• Engine Protector Clamp Bolt (10 mm)
• Spark Plug HT Terminal Nut (7 mm)
• Condenser Nut (7 mm)
19. Puncture Repair Kit
• Two Tyre Levers
• Two Tyre Valves
• Two Valve-Extracting Tyre Caps
• Inner Tube Repair Kit
20. Analogue Multimeter with 3 (or more) Resistance Ranges to check:
• 0.2 uF 500V DC Condenser
• Contact Breaker
• Magneto Coil
• HT Lead
• Front & Rear Bulbs
21. Cotton Cloth

TO remove the Magneto Rotor when replacing the Contact Breaker or Condenser, use a Magneto Rotor Extractor. A suitable Magneto Rotor Extractor may be made from two M10 x 50 mm Washers (each about 2 mm thick), one M8 Nut, one M8 x 50 mm Bolt and three M6 x 40 mm Bolts as shown below:

1. Braze-weld the M8 Nut to the centre of one of the M10 x 50 mm Washers
2. Braze-weld the two M10 x 50 mm Washers together
3. Drill three 6 mm diameter holes through the washers, 16 mm from the centre hole and 120° apart (27.7 mm between hole centres)
4. Make the thread end of the M8 x 50 mm Bolt conical using a flat file and screw the bolt about half-way into the M8 Nut
5. Using a Permanent Marker Pen put black marks about 7 mm from the ends of three M6 x 40 mm Bolts and insert the bolts into the M10 x 50 mm Washers as shown below

To remove the Magneto Rotor:

1. Prevent the Flywheel turning by using a Flywheel Clamp
2. Remove a 14 mm Centre Nut from the Magneto Rotor end of the Crankshaft
3. Remove a 75 mm Black Metal Plate and Rubber Seal
4. Remove a 14 mm Centre Nut and Washer
5. Pick up the Magneto Rotor Extractor assembly and screw the three M6 x 40 mm Bolts into the three Magneto Rotor holes until the black marks on the threads are just reached
6. Tighten the M8 x 50 mm Bolt against the centre of the Crankshaft end until you hear a sharp click and you will find that the Magneto Rotor can now be removed by hand

TO prevent the Flywheel turning when loosening or tightening the Crank Pin (Big-End) Bolt or when removing the Magneto Rotor:

1. Remove the M6 x 10 mm Bolt and Brass Washer beside the Fuel Pump (shown below)
2. Look into the resulting hole with a lamp and turn engine over slowly until flywheel is not blocking the hole
3. Screw in a M6 x 20 mm Bolt as a Flywheel Stop Bolt into the hole and tighten

WARNING! When you have finished the work you wish to do, make sure you replace the original M6 x 10 mm Bolt and Brass Washer

Another, perhaps stronger, way to prevent the Flywheel turning is to make your own Flywheel Clamp. This may be made from 20 mm x 20 mm x 105 mm (3 mm thick) right-angled mild steel using the pictures below:

Use two M6 Bolts taken from the Crankcase Cover and additional M6 nuts as spacers to secure the Flywheel Clamp to the two Crankcase holes shownbelow by arrows:

TO check that the VeloSoleX S 3800 has the correct Air-Fuel Mixture Ratio, one can use Gunson's Colortune:

The Colortune adaptor fits in place of the Spark Plug and having a clear window, one can see the Combustion Colour inside the Combustion Chamber while the engine is running. There are three main possible colours:

1.  Yellow  - Mixture Too Rich
2.  Bunsen Blue  - Mixture Correct
3.  Whitish Blue - Mixture Too Weak

There may also be a slight Red tinge to any of these colours due to the presence of oil in this 2-Stroke engine, which can normally be ignored.

TO check that the VeloSoleX S 3800 has the correct Cranking Compression Pressure, one can use Gunson's Hi-Gauge Compression Tester:

The Hi-Gauge Compression Tester adaptor fits in place of the Spark Plug of a fully warm engine. The throttle is kept wide open and the VeloSoleX S 3800 is pushed for a few metres before a reading is taken. A Reset Button, shown by the arrow above, allows subsequent readings to be taken.

A VeloSoleX S 3800 engine with little cylinder wear, good piston rings, good head gasket and good decompression valve seal should show a Cranking Compression Pressure reading of about 6.5 bars (95 PSI or 650 kPa).