Vespa would like to thank you for choosing one of its products. We have prepared this manual to help you to get the very best from your scooter. Please read it carefully before riding the scooter for the first time. It contains information, tips and precautions for using your scooter. It also describes features, details and devices to assure you that you have made the right choice.
The instructions given in this manual are intended to provide a clear, simple guide to using your scooter; this booklet also details routine maintenance procedures and regular checks that should be carried out on the vehicle at an authorised Dealer or Service Centre. The booklet also contains instructions for simple repairs.
Personal safety Failure to completely observe these instructions will result in serious risk of personal injury. Safeguarding the environment Sections marked with this symbol indicate the correct use of the vehicle to prevent damaging the environment. Vehicle intactness The incomplete or non-observance of these regulations leads to the risk of serious damage to the vehicle and sometimes even the invalidity of the guarantee. The signs that you see on this page are very important.
INDEX VEHICLE...................................................................................... Dashboard................................................................................ Clock......................................................................................... Key switch................................................................................. Locking the steering wheel.................................................... Releasing the steering wheel............................
VESPA Vespa LX 50 4T Chap.
01_01 Dashboard (01_01) A = Speedometer 1 Vehicle B = Odometer C = Fuel gauge D = Front brake control lever 8
F = Preset light G = High-beam warning light H = Low fuel warning light I = Low-beam/position light warning light L = High/low beam switch M = Turn indicator switch N = Horn button P = Starter button Q = Throttle grip R = Digital clock S = Real brake control lever Clock (01_02) Hours and minutes are displayed in a 1 to 12, AM or PM, format on the instrument panel. Operating the function selection switch «T» month, day and seconds can be seen besides hours and minutes.
WARNING DEAD BATTERIES ARE HARMFUL TO THE ENVIRONMENT. THEY MUST DISPOSED OF IN SUITABLE CONTAINERS AS PRESCRIBED BY THE REGULATIONS IN FORCE. Key switch (01_03) LOCK = Ignition disabled, extractable key, steering lock engaged front glove-box locked. OFF = Ignition disabled, extractable key, steering lock disengaged, front glove-box unlocked. ON = Starter position, antitheft device disabled, non-extractable key, glove-box unlocked.
DO NOT TURN THE KEY TO «LOCK» OR «OFF» WHILE RIDING. Switch direction indicators (01_04) To set the left turn indicators flashing, move lever «B» to the left; to set the right turn indicators flashing, move it to the right. The lever automatically returns to the central position and the indicators remain on. To turn the indicators off, press the lever towards the switch.
Light switch (01_06) 0 = Dipped beam and position light 1 = High beam and position light 01_06 Start-up button (01_07) To start the engine, press the starter button, «P», after pulling either one of the two brake levers. 01_07 Opening the saddle (01_08) 1 Vehicle Insert the key into the saddle lock «A», turn it anticlockwise and tip the saddle forward.
The vehicle is supplied with two keys (one spare) which serve to start the engine and unlock the saddle compartment. The keys are accompanied by a tag marked with the identification code to be quoted when ordering duplicates. WARNING WE RECOMMEND KEEPING THE DUPLICATE KEY TOGETHER WITH ITS CODE IN A SAFE PLACE AND NOT ON THE VEHICLE 01_09 Identification (01_10, 01_11) The identification numbers consist of a prefix stamped on the chassis and on the engine, followed by a number.
Rear top box opening (01_12) Turn the key to the position«OFF». Then press it. With the key is in «LOCK» the glovebox is locked. 01_12 Bag clip (01_13) To use the retractable bag hook «B» located at the front end of the saddle, pull it forward lightly.
VESPA Vespa LX 50 4T Chap.
Checks Before using the vehicle, check: 1. that the fuel tank is full. 2. The oil level in the rear hub. 3. engine oil level (see section «Engine oil level»). 4. That tyres are properly inflated. 5. correct functioning of headlights, rear taillight and turn indicators. 6. The correct functioning of the front and rear brakes. Refuelling (02_01) Fill fuel tank«A» with unleaded petrol (minimum octane rating = 95).
2 Use CAUTION USING OILS OTHER THAN THOSE RECOMMENDED CAN SHORTEN THE LIFE OF THE ENGINE. Characteristic Fuel tank capacity ~ 8.5 l (2 l of which is reserve) Tyre pressure CAUTION TYRE PRESSURE SHOULD BE CHECKED WHEN TYRES ARE COLD.INCORRECT TYRE PRESSURE CAUSES ABNORMAL TYRE WEAR AND MAKES RIDING DANGEROUS. TYRES MUST BE REPLACED WHEN THE TREAD REACHES THE WEAR LIMITS SET FORTH BY LAW. Characteristic Front tyre pressure 1.
Running in (02_02) WARNING 02_02 DURING THE FIRST 1000 KM DO NOT RIDE THE VEHICLE OVER 80% OF ITS MAXIMUM SPEED. AVOID TWISTING THE THROTTLE GRIP FULLY OR KEEPING A CONSTANT SPEED ALONG LONG SECTIONS OF ROAD. AFTER THE FIRST 1000 KM, GRADUALLY INCREASE SPEED UNTIL REACHING THE MAXIMUM PERFORMANCE. Starting up the engine (02_03) The vehicle is fitted with direct drive automatic transmission.
2 Use CAUTION DO NOT CARRY OUT THESE OPERATIONS IN CLOSED AREAS SINCE EXHAUST GASES ARE TOXIC. CAUTION ALWAYS PLACE THE VEHICLE ON ITS STAND BEFORE KICK STARTING. Precautions CAUTION NEVER STRESS THE ENGINE AT LOW TEMPERATURES IN ORDER TO AVOID POSSIBLE DAMAGE. BE CAREFUL NEVER TO EXCEED THE MAXIMUM SPEED WHILE RUNNING DOWNHILL, IN ORDER TO AVOID DAMAGING THE ENGINE.
Difficult start up (02_04) If there is a problem you can follow the instructions below: 1.Carburettor flooded. Place the vehicle on the centre stand and check that the rear tyre is off the ground. Open the throttle fully and press the starter button for five seconds and then stop for five seconds. If the engine does not start after a few attempts, let the engine sit for a few minutes and then repeat the above operations.
Stop acceleration, then turn the key switch "D" to "OFF " to turn off the engine (extractable key). CAUTION 02_05 DUE TO THE HIGH TEMPERATURES THE CATALYTIC CONVERTER CAN REACH, ALWAYS TAKE CARE, WHEN PARKING THE SCOOTER, THAT THE EXHAUST DOES NOT COME INTO CONTACT WITH FLAMMABLE MATERIALS, TO AVOID SERIOUS BURNS. Automatic transmission To ensure simple, pleasurable riding, the vehicle is equipped with automatic transmission with regulator and centrifugal clutch.
Safe driving WARNING SOME SIMPLE TIPS ARE PROVIDED BELOW THAT WILL ENABLE YOU TO USE YOUR SCOOTER ON A DAILY BASIS IN GREATER SAFETY AND WITH MORE PEACE OF MIND. < Your ability and your knowledge of the vehicle form the basis of safe riding. We recommend trying out the vehicle in traffic-free zones to get to know your vehicle completely. ALWAYS DRIVE WITHIN YOUR LIMITS 1. Before riding off, remember to put on your helmet and fasten it correctly. 2. Reduce speed and ride cautiously on uneven roads. 3.
CAUTION DO NOT FORGET THAT DRIVING IN A STATE OF DRUNKENNESS, OR WHEN UNDER THE EFFECT OF DRUGS OR CERTAIN MEDICINES, CAN BE EXTREMELY DANGEROUS FOR ONESELF AND FOR OTHERS. CAUTION ANY CHANGES TO THE VEHICLE PERFORMANCE AS WELL AS ALTERATIONS TO ORIGINAL STRUCTURAL PARTS IS STRICTLY FORBIDDEN BY LAW, AND RENDERS THE VEHICLE NO LONGER CONFORMING TO THE APPROVED TYPE AND DANGEROUS FOR RIDING. 23 2 Use 8.
2 Use
VESPA Vespa LX 50 4T Chap.
Engine oil level In 4T engines, the engine oil is used to lubricate the distribution elements, the bench bearings and the thermal group. An insufficient quantity of oil can cause serious damage to the engine itself. In all 4T engines the decay of oil characteristics as well as some consumption is normal. Consumption can particularly reflect the conditions of use (i.e. when driving at "full acceleration" all the time, oil consumption increases).
Always check oil level before carrying out top-ups and add oil without exceeding the MAX level. An engine oil check-up and top-up should be carried out every 3,000 km at an Authorised Piaggio Service Centre. Engine oil change (03_03) Change oil and clean the filter after every 6,000 km at an Authorised Piaggio Service Centre. Empty the engine by draining the oil through drainage cap «C» with a cold engine.
Hub oil level (03_04, 03_05, 03_06) To check the hub oil level, proceed as follows: 1. Place the scooter on its stand on a level surface; 2. Unscrew the dipstick «A», dry it with a clean rag and then reinsert it, screwing it tightly into place; 3. Unscrew the dipstick again and check that the oil level barely reaches the 2nd notch from the bottom; 4. Screw the dipstick back into place completely. The screw «B» is the hub oil drainage tap.
Characteristic Rear hub oil Quantity: approx. 85 cc Tyres (03_07) Periodically check the inflation pressure of each tyre (when cold). The tyres are fitted with a wear indicator and must be replaced as soon as such indicator appears on the tread. Also ensure that the tyres do not show cuts on the walls or an irregular wear of the tread; if this is the case, please contact an authorised or adequately equipped workshop. CAUTION 03_07 TYRE PRESSURE SHOULD BE CHECKED WHEN TYRES ARE COLD.
Spark plug dismantlement (03_08, 03_09, 03_10, 03_11) The engine must be cold to inspect the sparkplug, proceed as follows: 1. Lift the saddle and remove the helmet compartment "A"; 2. Remove the sparkplug inspection door "B"; 3. Remove plug cap "C"; 4. Use the equipped spanner "D"(with rubber stop) and a 13 mm spanner to remove the sparkplug.
3 Maintenance NGK CR 8EB 03_11 Removing the air filter (03_12, 03_13) Remove the side fairing unscrewing the 2 screws marked A. Remove the air cleaner cap «D» after unscrewing the 6 fixing screws «C», then remove the filtering element. Clean with water and shampoo, afterwards dry with compressed air and submerge in a recommended oil and petrol mixture in ratio of 50%. Afterwards squeeze it, leave it to dry and mount it again.
Secondary air system (03_14, 03_15, 03_16, 03_17) Use the two screws "A" on the right side panel and remove it. Use the three screws "B" to remove the cover of the secondary air box. Move the cover of the box away and remove the sponge filter "C". Wash the sponge with water and a neutral soap, and dry it with a clean rag and shorts blasts of compressed air. When cleaning the filter, make sure the reed valve "D" is in good condition then reinsert it in its seat on the box.
3 Maintenance 03_17 Checking the brake oil level (03_18, 03_19) The brake fluid reservoir is equipped with a sight glass «A» made of transparent material; the quantity of liquid contained in the sight glass indicates the level of liquid in the reservoir. When the sight glass «A» is full, the level inside the reservoir exceeds the MIN level; when it is partially full, the level drops to the MIN level; when it is fully empty, the level of fluid in the reservoir is below the MIN level.
WARNING IN NORMAL CLIMATIC CONDITIONS IT IS ADVISABLE TO REPLACE THE ABOVE-MENTIONED FLUID EVERY 2 YEAR. NEVER USE BRAKE FLUID CONTAINED IN CONTAINERS WHICH ARE ALREADY OPEN OR PARTIALLY USED. CAUTION 03_19 THE BRAKING CIRCUIT FLUID IS HIGHLY CORROSIVE. THEREFORE, WHEN TOPPING IT UP, AVOID LETTING IT COME INTO CONTACT WITH THE PAINTED PARTS OF THE VEHICLE. THE BRAKING CIRCUIT FLUID IS HYGROSCOPIC, WHICH MEANS THAT IT ABSORBS MOISTURE FROM THE SURROUNDING AIR.
ELECTROLYTE CONTAINS SULPHURIC ACID: AVOID CONTACT WITH EYES, SKIN AND CLOTHES. IN THE CASE OF ACCIDENTAL CONTACT, RINSE WITH ABUNDANT OF WATER AND CONSULT A DOCTOR. CAUTION IN ORDER TO AVOID DAMAGING THE ELECTRICAL SYSTEM, NEVER DISCONNECT THE WIRING WHILE THE ENGINE IS RUNNING. DO NOT TIP THE SCOOTER TOO MUCH IN ORDER TO AVOID DANGEROUS LEAKAGE OF BATTERY ELECTROLYTE . Checking the electrolyte level The electrolyte level, which should be checked regularly, must always be at the maximum level.
Long periods of inactivity Battery performance will decrease if the vehicle is not used for a long time. This is the result of the natural phenomenon of battery discharging plus residual absorption by vehicle components with constant power consumption. Poor battery performance may also be due to environmental conditions and the cleanness of the poles.
SPENT BATTERIES ARE HARMFUL FOR THE ENVIRONMENT. COLLECTION AND DISPOSAL SHOULD BE CARRIED OUT IN COMPLIANCE WITH CURRENT REGULATIONS. Fuses (03_21) The electrical system is protected by a 10A fuse valve «B» located next to the battery. Before replacing a blown fuse, find and solve the problem that caused it to blow. Do not substitute the fuse with any alternative form of conductor CAUTION 03_21 IN ORDER TO AVOID DAMAGING THE ELECTRICAL SYSTEM, NEVER DISCONNECT THE WIRING WHILE THE ENGINE IS RUNNING.
Power: 12V 5W Quantity: 1 Instrument panel light bulbs Type: All glass Power: 12V 1.2W Quantity: 3 Front turn indicator bulb Type: Spherical Power: 12V - 10W Quantity: 1 RHS + 1 LHS Rear turn indicator light bulb Type: Spherical Power: 12V - 10W Quantity: 1 RHS + 1 LHS Stop and tail light bulb Type: Spherical Power: 12V 21/5W Quantity: 1 12V - 2W warning light bulbs Type: All glass Function: Turn indicators 3 Maintenance Quantity: 2 12V - 1.
To access the headlight bulbs, remove the front of the handlebar cover, as follows: 1) Remove the rear-view mirrors; for this operation follow the instructions described and illustrated in «Rear-view mirrors» section. 2) Unscrew the 3 screws holding the handlebar cover. The front central one «B» and the rear 2 «C». Once this is done, the handlebar cover can be removed. 3) Remove the handlebar cover to access the headlight and the bulbs. 03_22 N.B.
2. Turn on the headlight and check that the borderline of the projected light beam on the screen is not lower than 9/10 of the distance from the ground to the centre of vehicle headlamp and higher than 7/10; 3. If otherwise, adjust the right headlight with screw «A». N.B. THE ABOVE PROCEDURE COMPLIES WITH THE EUROPEAN STANDARDS REGARDING MAXIMUM AND MINIMUM HEIGHT OF LIGHT BEAMS. REFER TO THE STATUTORY REGULATIONS IN FORCE IN EVERY COUNTRY WHERE THE vehicle IS USED.
THE PRESENCE OF DROPS OF WATER, ON THE OTHER HAND, COULD INDICATE THAT WATER IS INFILTRATING. CONTACT THE PIAGGIO AFTER-SALES SERVICE NETWORK. Rear turn indicators (03_28) To gain access to the turn indicator bulbs, remove the fastening screws «E». The bulbs have a bayonet coupling, to remove them press gently and twist anticlockwise about 30°. To refit follow the same steps but in reverse order. 03_28 Rear-view mirrors (03_29) The mirrors can be set to the desired position by adjusting the mirror frame.
Idle adjustment (03_30) Proceed as follows: 1. Rest the scooter on its centre stand and lift the saddle (as described in the «Saddle opening to reach helmet compartment» section). 2. Remove the helmet compartment. 3. To adjust the idle speed, start the engine, then loose or tighten the screw «B» until you reach the recommended idle speed taking care the engine does not make the rear wheel move.
The brake disc and pad wear is automatically compensated, therefore it has no effect on the functioning of the front and rear brakes. For this reason it is not necessary to adjust the brakes. An excessively elastic brake lever stroke may indicate the presence of air in the braking circuit or an irregular brake operation.
Rear drum brake (03_32) Operate adjustment nut «B» and loosen lock nut «A» shown in the figure. Note that when the throttle is in idle the wheel should rotate free. After the adjustment, screw lock nut «A». CAUTION 03_32 THE BRAKING ACTION SHOULD BEGIN AFTER ABOUT 1/3 OF THE BRAKE LEVER STROKE. Puncture (03_33) The vehicle is equipped with Tubeless tyres. When there is a puncture, Tubeless tyres - unlike tyres with inner tubes - go flat very slowly. This offers greater riding safety.
5 - Drain the petrol from the carburettor tank. 6 - Replace engine oil. Recommended products AGIP CITY HI TEC 4T Oil to lubricate flexible transmissions (brakes, throttle control and odometer) Oil for 4-stroke engines Cleaning the vehicle Use a low pressure jet of water to soften the caked dirt and mud deposited on the painted surfaces. Once softened, sponge off mud and dirt using a car body sponge soaked in a car body shampoo and water solution (2-4% of car shampoo in water).
PLASTIC SURFACES, TO PREVENT THEM LOSING THEIR SHINE AND MECHANICAL CHARACTERISTICS. WARNING WHEN WASHING THE ENGINE WITH A HIGH-PRESSURE WATER JET: • ONLY USE FAN SPRAY JETS. • DO NOT PLACE THE WATER JET NOZZLE CLOSER THAN 60 CM. • DO NOT USE WATER AT TEMPERATURES OVER 40° C. • DO NOT DIRECT THE JETS DIRECTLY TO CARBURETTOR, WIRING, SLOT DIFFUSER ON THE TRANSMISSION COVER AND SCROLL COVER. DIFFICULTY STARTING No fuel in tank Refuelling Filters, jets or carburettor dirty or clogged.
3 Maintenance there are any cracks or breakage, replace the spark plug. If the spark plug is in good condition, contact an Authorised Piaggio Service Centre. LACK OF COMPRESSION Spark plug adapter "worn", valve clearance not adequate; worn piston gas rings Contact an Authorised Service Centre. HIGH CONSUMPTION AND LOW PERFORMANCE Air filter blocked or dirty.
IRREGULAR AUTOMATIC TRANSMISSION Deteriorated roller container or belt. Contact an Authorised Service Centre. INCREASED EXHAUST NOISE Deterioration of the SAS system and/or of the tab Contact an Authorised Service Centre.
VESPA Vespa LX 50 4T Chap.
4 Technical data 04_01 50
4 Technical data TECHNICAL SPECIFICATIONS Engine type Single cylinder 4-stroke Piaggio HiPER4 Cubic capacity 49.9 cc Bore x stroke 39 X 41.8 mm Compression ratio 11.5 :1 Length 1755 mm Width 740 mm Overall height 1140 mm Wheel base 1290 mm. Fuel Unleaded petrol Chassis Unitised body made of stamped plate. Fuel tank capacity ~ 8.
Steering and suspensions Fulcrum steering tube on the front wheel-holder hub; helicoidal spring suspension and double-acting hydraulic shock absorber; rear with single chamber hydraulic shock absorber and coaxial spring not adjustable at preloading Rear tyre Tubeless; 120/70-10" Front tyre Tubeless; 110/70-11" Rear wheel rim Die-cast aluminium alloy; 3.00 x 10" Front wheel rim Die-cast aluminium alloy; 2.
VESPA Vespa LX 50 4T Chap.
Warnings (05_01, 05_02) WARNING IT IS ALSO RECOMMENDED THAT "ORIGINAL PIAGGIO SPARE PARTS" BE USED, AS THESE ARE THE ONLY ONES OFFERING YOU THE SAME QUALITY ASSURANCE AS THOSE INITIALLY FITTED ON THE VEHICLE. IT SHOULD BE REMEMBERED THAT USING NON-ORIGINAL SPARE PARTS CAUSES YOUR WARRANTY RIGHTS TO EXPIRE. WARNING 5 Spare parts and accessories 05_01 PIAGGIO MARKETS ITS OWN LINE OF ACCESSORIES THAT ARE RECOGNISED AND GUARANTEED FOR USE.
VESPA Vespa LX 50 4T Chap.
Scheduled maintenance table Adequate maintenance is fundamental to ensuring long-lasting, optimum operation and performance of your vehicle. To this end, a series of checks and maintenance operations (at the owner's expense) have been suggested, which are included in the summary table on the following page. Any minor faults should be reported without delay to an Authorised Service Centre or Dealer without waiting until the next scheduled service to solve it.
6 Programmed maintenance Steering - adjustment Brake control levers - greasing Brake pads - check condition and wear Brake fluid level - check Safety locks - check Electrical system and battery - check Tyre pressure - check Vehicle and brake test - road test (*) See instructions in «Idle speed adjustment» section AT 6000 KM OR 12 MONTHS, 18000, 30000, 42000, 54000 AND 66000 KM Engine oil - replacement Hub oil level - check Spark plug / electrode gap - check Oil filter (net filter) - clean Variable speed r
AT 12000 KM OR 24 MONTHS AND 60000 KM Engine oil - replacement Hub oil level - check Spark plug/electrode gap - replacement Air filter - clean Oil filter (net filter) - clean Idle speed (*) - adjustment Throttle lever - adjustment Variable speed rollers - check or replacement Driving belt - replacement Odometer cable - greasing Steering - adjustment Brake control levers - greasing Brake pads - check condition and wear 6 Programmed maintenance Brake fluid level - check Transmission elements - lubrication S
6 Programmed maintenance Vehicle and brake test - road test (*) See instructions in «Idle speed adjustment» section (**) See regulations in the «Secondary air system» section A 24000 KM AND 48000 KM Engine oil - replacement Hub oil level - replacement Spark plug/electrode gap - replacement Air filter - clean Oil filter (net filter) - clean Valve clearance - check Idle speed/carburetion - Adjustment (*) Throttle lever - adjustment Variable speed rollers - check or replacement Driving belt - replacement Cyl
Safety locks - check Suspensions - check Electrical system and battery - check Headlight - adjustment Tyre inflation and wear - Check Vehicle and brake test - road test AT 36000 KM Engine oil - replacement Hub oil level - check Spark plug/electrode gap - replacement Air filter - clean Oil filter (net filter) - clean Idle speed (*) - adjustment 6 Programmed maintenance Throttle lever - adjustment Variable speed rollers - check or replacement Driving belt - replacement Odometer cable - greasing Steering -
6 Programmed maintenance Brake fluid level - check Transmission elements - lubrication Safety locks - check Suspensions - check Electrical system and battery - check Headlight - adjustment Tyre inflation and wear - Check SAS box (sponge) (**) - cleaning Vehicle and brake test - road test (*) See instructions in «Idle speed adjustment» section (**) See regulations in the «Secondary air system» section AFTER 72,000 KM Engine oil - replacement Hub oil - change Spark plug/electrode gap - replacement Air filte
Driving belt - replacement Cylinder ventilation system - check Odometer cable - greasing Steering - adjustment Brake control levers - greasing Brake pads - check condition and wear Flexible brake tubes - replacement Brake fluid level - check Transmission elements - lubrication Safety locks - check Suspensions - check Electrical system and battery - check Headlight - adjustment Tyre inflation and wear - Check 6 Programmed maintenance SAS box (sponge) (**) - cleaning Vehicle and brake test - road test (*) S
Product Description Specifications AGIP ROTRA 80W-90 Rear hub oil SAE 80W/90 Oil that exceeds the requirements of API GL3 specifications AGIP BRAKE 4 Brake fluid FMVSS DOT 4 Synthetic fluid AGIP CITY HI TEC 4T Oil to lubricate flexible transmissions (brakes, throttle control and odometer) Oil for 4-stroke engines AGIP FILTER OIL Oil for air filter sponge Mineral oil with specific additives for increased adhesiveness AGIP CITY HI TEC 4T Engine oil SAE 5W-40, API SL, ACEA A3, JASO MA Syntheti
6 Programmed maintenance
TABLE OF CONTENTS A H S Air filter: 31 Headlight: 39 Horn: 11 Hub oil: 28 Saddle: 12 Scheduled maintenance: 56 Spark plug: 30 Start-up: 12 B Battery: 34 Brake: 33, 43, 44 I T Identification: 13 C Clock: 9 Technical Data: 49 Top box: 14 Transmission: 21 Turn indicators: 41 Tyre pressure: 17 Tyres: 29 K Key switch: 10 Keys: 13 D Disc brake: 43 L Light switch: 12 E Engine oil: 26, 27 M F Maintenance: 25, 55, 56 Mirrors: 41 Fuses: 37 65
The descriptions and illustrations given in this publication are not binding. While the basic features as described and illustrated in this manual remain unchanged, PIAGGIO - GILERA reserves the right, at any time and without being required to update this publication beforehand, to make any changes to components, parts or accessory supplies, which it considers necessary to improve the product or which are required for manufacturing or construction reasons.
