Browse F.A.Q. Topics
Engine
What spark plug have I to fit on my power unit?
Please, check the assembling instructions of the kit you have fitted.What’s the difference between piston A, B, C or D?
The piston with letter A has the smallest diameter, while the one with letter D is the biggest one. Every different letter means an increase of 0,01 mm.What kind of oil may I use for the mixture? In what percentage?
Use 2% synthetic oilHow much tolerance must the piston have with the aluminium cylinder?
The foreseen tolerance must be included between 3 and 3 cents (0,03 - 0,06)How much tolerance must the piston have with the cats-iron cylinder?
The foreseen tolerance must be included between 6 and 8 cents (0,06 - 0,08)How can I find the displacement of a power kit?
The displacement can be calculated through the following formula: Displacement= (DxDx3,1416xC)/4=DxDxCx0,7854 D=Bore (the piston's diameter) C= Stroke (distance between top and bottom dead centre)When have I to change my piston?
It depends on the cylinder kit you have fitted and on what kind of races you take part in. Generally a standard cast iron cylinder the piston lasts 5000/8000 km. The cast iron racing type can last 3000/5000 km, the evolution aluminium ones 500/1000 km. If your engine has been tuned up to take part to the Polini Italian Cup you have to change the piston every two races.When Have I to change the ring?
The wear of the ring should be the same as the piston. We do not recommend changing the ring only.I have just fitted a new 4 stroke cylinder and it makes a lot of smoke. What may I do?
Probably when assembling the piston, the spring located under the 2 scraper rings has broken. Change all the rings.Why is Polini ignition better than the standard unit? What are the advantages?
The most important advantage of the Polini ignition is the rotor. The flywheel inertial mass has been drastically reduced and you immediately find a better pick up. The advance curve has been studied for every kind of use of the engine and it has been personalised according to the brand and model.If I fit one of your “freer” air filters, do I to change the jets?
Yes, you have. Usually it is enough to increase the main jet. We suggest immediately increasing of 10 points and then adjust it according to the carburetion.I’m fitting my new piston. What’s the direction of the arrow I find on the top of the piston?
The arrow must be directed towards the exhaust port.
General
Are there any Polini technical service points?
There are no Polini's technical service points. For any questions relating to Polini parts please apply to your nearest retailerWhat have I to do if I receive a defective part?
Please, read the certificate of warranty included in every item.What have I to do to participate in the Polini Italian Cup?
Please, find all the information by visiting the races area on our web site.Is it possible to talk to the technicians at Polini?
It is not possible to directly talk to the technicians at Polini. For any information please apply to the nearest retailer who will get in contact with the Polini's technicians if they do not know the answer to your request.I have a problem with one of your products. What have I to do?
Please, read the certificate of warranty included in every item.
Minibikes/ Minicross
How can I adjust the spark advance of my minibike?
It is not possible to modify the spark advance because it is fixed. On the other hand it is possible to time the flywheel by placing a 0,3 mm shim between the rotor and the coil.Where can I find the part number for the minicross spare parts?
Visit our web section "minicross/minimotard".Where can I find the part number for the minibikes spare parts?
Visit our web section "minibike"Where can I find the item’s code for the XP4 bikes spare parts?
Visit our web section "minicross/minimotard".Is the XP 125cc bike homologated for a passenger too?
No. It can be driven by the driver only. No passengers allowed.Is it possible to use the 125 XP4 bike during the driving test to get the driving license?
No, it is not possible because the speed indicated in the certificate of conformity doesn't meet all the requirements asked from the law to get the driving licenceCan I drive my minibike on the public way?
NO, YOU CAN'T! It is forbidden by the law. The minibikes are not homologated to be driven on the public roadway.Can I fit hydraulic brakes on my GP3 or GP4 minibikes?
No, you can't. There are no hydraulic brakes available for this model.What’s approximately is the maximum speed a minibike can reach?
Maximum speed data does not exist. The minibikes are divided into categories according to their power. Take into consideration that the less powerful minibikes with 4,2 hp can reach 40/50kmh. The most powerful with 15hp can reach 100 kmh.How much oil may I put in the minibike Reverse engine?
Use 6 cc. of Sae 10W-30 oil type. See the use and maintenance manual.
Technical Faq
Are there any Polini technical service points?
There are no Polini's technical service points. For any questions relating to Polini parts please apply to your nearest retailerWhat have I to do if I receive a defective part?
Please, read the certificate of warranty included in every item.What have I to do to participate in the Polini Italian Cup?
Please, find all the information by visiting the races area on our web site.Is it possible to talk to the technicians at Polini?
It is not possible to directly talk to the technicians at Polini. For any information please apply to the nearest retailer who will get in contact with the Polini's technicians if they do not know the answer to your request.I have a problem with one of your products. What have I to do?
Please, read the certificate of warranty included in every item.How can I adjust the spark advance of my minibike?
It is not possible to modify the spark advance because it is fixed. On the other hand it is possible to time the flywheel by placing a 0,3 mm shim between the rotor and the coil.Where can I find the part number for the minicross spare parts?
Visit our web section "minicross/minimotard".Where can I find the part number for the minibikes spare parts?
Visit our web section "minibike"Where can I find the item’s code for the XP4 bikes spare parts?
Visit our web section "minicross/minimotard".Is the XP 125cc bike homologated for a passenger too?
No. It can be driven by the driver only. No passengers allowed.Is it possible to use the 125 XP4 bike during the driving test to get the driving license?
No, it is not possible because the speed indicated in the certificate of conformity doesn't meet all the requirements asked from the law to get the driving licenceCan I drive my minibike on the public way?
NO, YOU CAN'T! It is forbidden by the law. The minibikes are not homologated to be driven on the public roadway.Can I fit hydraulic brakes on my GP3 or GP4 minibikes?
No, you can't. There are no hydraulic brakes available for this model.What’s approximately is the maximum speed a minibike can reach?
Maximum speed data does not exist. The minibikes are divided into categories according to their power. Take into consideration that the less powerful minibikes with 4,2 hp can reach 40/50kmh. The most powerful with 15hp can reach 100 kmh.How much oil may I put in the minibike Reverse engine?
Use 6 cc. of Sae 10W-30 oil type. See the use and maintenance manual.What spark plug have I to fit on my power unit?
Please, check the assembling instructions of the kit you have fitted.What’s the difference between piston A, B, C or D?
The piston with letter A has the smallest diameter, while the one with letter D is the biggest one. Every different letter means an increase of 0,01 mm.What kind of oil may I use for the mixture? In what percentage?
Use 2% synthetic oilHow much tolerance must the piston have with the aluminium cylinder?
The foreseen tolerance must be included between 3 and 3 cents (0,03 - 0,06)How much tolerance must the piston have with the cats-iron cylinder?
The foreseen tolerance must be included between 6 and 8 cents (0,06 - 0,08)How can I find the displacement of a power kit?
The displacement can be calculated through the following formula: Displacement= (DxDx3,1416xC)/4=DxDxCx0,7854 D=Bore (the piston's diameter) C= Stroke (distance between top and bottom dead centre)When have I to change my piston?
It depends on the cylinder kit you have fitted and on what kind of races you take part in. Generally a standard cast iron cylinder the piston lasts 5000/8000 km. The cast iron racing type can last 3000/5000 km, the evolution aluminium ones 500/1000 km. If your engine has been tuned up to take part to the Polini Italian Cup you have to change the piston every two races.When Have I to change the ring?
The wear of the ring should be the same as the piston. We do not recommend changing the ring only.I have just fitted a new 4 stroke cylinder and it makes a lot of smoke. What may I do?
Probably when assembling the piston, the spring located under the 2 scraper rings has broken. Change all the rings.Why is Polini ignition better than the standard unit? What are the advantages?
The most important advantage of the Polini ignition is the rotor. The flywheel inertial mass has been drastically reduced and you immediately find a better pick up. The advance curve has been studied for every kind of use of the engine and it has been personalised according to the brand and model.If I fit one of your “freer” air filters, do I to change the jets?
Yes, you have. Usually it is enough to increase the main jet. We suggest immediately increasing of 10 points and then adjust it according to the carburetion.I’m fitting my new piston. What’s the direction of the arrow I find on the top of the piston?
The arrow must be directed towards the exhaust port.What is the compression spring for?
The compression spring is for a better calibration of the transmission. The stiffer spring helps the spring to transmit the power of the scooter to the wheel. In this way the variator too can give the best power.What’s the difference between primary gear and secondary gear? Which ones better to achieve more speed?
There is no difference between primary and secondary gear. In the Polini catalogue you can find a schedule indicating the number of teeth of each POLINI gear and that can help you to find the fastest one.What’s the variator performance?
All the Polini variators have been studied and tested on all the scooters brands and models. They have been all tested on the original engine without the power unit. The main feature of all the Polini variator is the increase of the variator range. Usually it is possible to modify the pulley ratio on the belt obtaining in this way a short gear for the starting and a longer gear exploit the maximum speed of your scooter.How can I calibrate the clutch?
The clutch is very important because it represents the pickup when starting: it's the acceleration. The Polini clutches, all but the EVOLUTION ones, are delivered with a coupling range calibrated for the original scooters. In the adjustable clutches it is possible to modify the pick up time at your choice But be careful not to over exaggerate this adjustment or you run the risk of burning the clutch out after only a few starts.How can I calibrate the transmission?
When setting up your scooter the last operation to make is the transmission calibration. First of all, you have to check that the engine is not defective. If you want to set up a scooter the best thing to do is to buy a POLINI variator. If you have already assembled a standard Polini muffler it is enough to modify the rollers calibration and change with a lighter serie. If you also fit a power unit we suggest adding the gears that let you a better set up of the transmission. If you decide to fit an EVOLUTION cylinder kit it is necessary to fit the corresponding EVOLUTION transmission you find in the POLINI catalogue.What will happen if I fit lighter or heavier rollers?
People think that the lighter rollers are for the pickup and the heavier ones for the speed. This is not completely true. Rollers of different grams are to calibrate your scooter according to the engine set up. The rollers aim is to match as much as is possible the speed range to the engine rev at the maximum power. In this way you achieve the best acceleration and the best speed that your scooter can generate.What will happen if I change the inclination of the cam of a torque calibrator?
The torque calibrator is indicated for the tuned-up scooters that need to increase the number of revolution of the variator, as for example the EVOLUTION engines. The more inclined cams oppose to the belt opening, increasing the number of revolutions of the transmission.I have to choose the gears for my bike: how can I find them in the catalogue?
The schedules are divided according to the scooter brand and model and Polini suggests a specific gear for them. Attention: for Piaggio models see the dedicated schedule.How much is the speed increase if I change the primary or the secondary gear?
The speed increases according to the teeth of the gear and to the engine power. If you increases the gear too much it must be adequate to the engine power. An Evolution gear on a standard scooter will only worsen the acceleration.When have I to change the rollers weights of my variator?
Rollers must be changed as part of the normal service of your scooter. Please look at your use and maintenance manual.
Trade Faq
What am I supposed to do if the spare part or the product I need is not available by your dealer?
If it is not possible to find a product available by one of our retailers, it is sufficient that you order that product by one of the retailers listed in our web site, which then will activate itself and stock up with it.Where can I find the price list of the products?
You can get information about Polini products' prices by turning to the authorized retailers or visitng our online catalogue .Where can I find the nearest Polini dealer?
Click on this area in order to enter our dealer map and find the nearest to you.Is it possible to directly purchase products in your head office?
We are sorry, but we do not directly sell from our head office in Alzano Lombardo. In order to purchase our products it is necessary to turn to our points of sale.I have ordered a product months ago but it does not seem to arrive. What am I supposed to do?
Please apply to the shop where you ordered the product.Could you send me some stickers?
You can find them at our authorized dealers. Visit the section dealer on the site: you can find the local dealer closest to you.Could you please send me the updated catalogue?
By visiting our website you can enter our online catalog section: an always up-to-date device that can be easily consulted and that can help you finding the most suitable spare part to meet your needs. Otherwise, you can turn to your area retailer. Visit our web section to find out the nearest dealer to you.Can I directly purchase products from you? I have a VAT number, but I do not work in the car/motorbike sector.
Please send a written request with a short description of your society and all your data to the following e-mail address: news@polini.com Each request will be evaluated from the export manager and you will be contacted as soon as possible by our staff.Can I directly purchase products from you? I am a private consumer.
Polini Motori does not sell directly to private customers. You can buy on our shop at www.polini.shop (for European countries only) or from one of our points of sale.Can I enter the reserved area?
The reserved area is dedicated only to foreign customers.Could you please send me your updated price list?
Polini Motori sends its own price list to authorized retailers only. Visit our web section to find out the nearest dealer.Could you send me some information about your products?
On our website you will find updated information about our products and events related to our company. Or you can go to one of our authorized dealer: see dealer.Can I purchase products during the trade fair?
We are sorry, but we do not sell products during trade fairs.I’d like to become one of your dealers. What do I have to do?
Please send a written request with a short description of your society and all your data to the following e-mail address: news@polini.com Each request will be evaluated from the export manager and you will be contacted as soon as possible by our staff.
Transmissions
What is the compression spring for?
The compression spring is for a better calibration of the transmission. The stiffer spring helps the spring to transmit the power of the scooter to the wheel. In this way the variator too can give the best power.What’s the difference between primary gear and secondary gear? Which ones better to achieve more speed?
There is no difference between primary and secondary gear. In the Polini catalogue you can find a schedule indicating the number of teeth of each POLINI gear and that can help you to find the fastest one.What’s the variator performance?
All the Polini variators have been studied and tested on all the scooters brands and models. They have been all tested on the original engine without the power unit. The main feature of all the Polini variator is the increase of the variator range. Usually it is possible to modify the pulley ratio on the belt obtaining in this way a short gear for the starting and a longer gear exploit the maximum speed of your scooter.How can I calibrate the clutch?
The clutch is very important because it represents the pickup when starting: it's the acceleration. The Polini clutches, all but the EVOLUTION ones, are delivered with a coupling range calibrated for the original scooters. In the adjustable clutches it is possible to modify the pick up time at your choice But be careful not to over exaggerate this adjustment or you run the risk of burning the clutch out after only a few starts.How can I calibrate the transmission?
When setting up your scooter the last operation to make is the transmission calibration. First of all, you have to check that the engine is not defective. If you want to set up a scooter the best thing to do is to buy a POLINI variator. If you have already assembled a standard Polini muffler it is enough to modify the rollers calibration and change with a lighter serie. If you also fit a power unit we suggest adding the gears that let you a better set up of the transmission. If you decide to fit an EVOLUTION cylinder kit it is necessary to fit the corresponding EVOLUTION transmission you find in the POLINI catalogue.What will happen if I fit lighter or heavier rollers?
People think that the lighter rollers are for the pickup and the heavier ones for the speed. This is not completely true. Rollers of different grams are to calibrate your scooter according to the engine set up. The rollers aim is to match as much as is possible the speed range to the engine rev at the maximum power. In this way you achieve the best acceleration and the best speed that your scooter can generate.What will happen if I change the inclination of the cam of a torque calibrator?
The torque calibrator is indicated for the tuned-up scooters that need to increase the number of revolution of the variator, as for example the EVOLUTION engines. The more inclined cams oppose to the belt opening, increasing the number of revolutions of the transmission.I have to choose the gears for my bike: how can I find them in the catalogue?
The schedules are divided according to the scooter brand and model and Polini suggests a specific gear for them. Attention: for Piaggio models see the dedicated schedule.How much is the speed increase if I change the primary or the secondary gear?
The speed increases according to the teeth of the gear and to the engine power. If you increases the gear too much it must be adequate to the engine power. An Evolution gear on a standard scooter will only worsen the acceleration.When have I to change the rollers weights of my variator?
Rollers must be changed as part of the normal service of your scooter. Please look at your use and maintenance manual.