Final transmissions (chain, sprocket) for motorbikes (made by PBR Sprockets - Italy & EK - Japan)

Rear sprockets are all made of Ergal 7075 T6, and they are grey colour anodizing processed (or red colour, as mentioned in the notes of the relevant code). They are very resistant, light and long lasting. Weight of ergal sprocket, compared to steel one, is less than 50%, and its duration is about 2/3 of the steel one. In some cases (as mentioned in the notes of corresponding codes), they may undergo a further hard anodizing treatment, which considerably improves hardness and therefore resistance to abrasion and corrosion.


Rear sprockets

 

Front sprockets

Semifinished ergal rear sprockets are also available.

Front sprockets are made of 18NCD5 steel and for some of them the version with lightening holes is available.

In order to easily remove the front sprockets avoiding it to rotate, we advise to keep the rear wheel still by braking and engaging first gear. Once the front sprocket removed, accurately clean the small shaft before mounting the new sprocket on it.

Chains are made by EK (Japan) and are natural gray, green, red, gold or blue colour. Pin or clip links are included in the packaging. In some cases, both of them are included but it is always advisable to use the pin link if available. If you are going to use the clip link, also use some red silicone to avoid its slipping off due to vibrations.

For the chains, on our site, you can find spare links, the tool for cutting, tightening and riveting and the grease remover / lubricant.

  

Applications for standard / stock final transmissions
Applications for racing final transmissions

Rear sprockets specific for Marvic wheels and for Marchesini / PVM / BST / TWM wheels are further available.

  

By choosing the ratios, 1 front sprocket cog is equal to about 3 rear sprocket cogs (the exact ratio is given by: number of rear sprocket teeth / number of front sprocket teeth).
The above stated, ratios have to be chosen in a way that a max. difference of 2 cogs is not exceeded. This way, you can always keep the same chain length. The Kawasaki ZX-10R Ninja is an exception: a rear chain with over 1 tooth more than the stock one cannot be used, since length of stock chain will not allow that. Remember that if you want more acceleration you have to mount a rear sprocket with more toothing, or a front sprocket with lower toothing. Ratios have to be necessarily and exclusively chosen by yourself. It is usual to mount a rear sprocket with 2 teeth more than the stock one, but that is however a medium choice which does not mean to be satisfying to everybody.
In a circuit, generally the right final ratio will be that allowing to achieve, at the highest gear, about 200 rpm more than the max power rate, always staying 200/300 rpm under the maximum rate the engine can reach. This way, you can take advantage of the trail of the driver who is preceding you.
Choosing the final ratio, remember that the bigger it is, the more the acceleration will be. But if it is too big, you will lose speed. If on the contrary the ratio is too small, you will lose acceleration and will not manage to reach the maximum speed.

If your final transmission has exceeded 5000 km, we advise not to change only one of the three components, but to change them altogether (chain,rear and front sprockets). This, because final transmission would otherwise deteriorate in very few kilometres.

For the best working and longer duration of the transmission, it needs to be cleaned and lubricated every 1000 Km at least, using our specific cleaner and lubricant for chains.

Different toothing for front and rear sprocket are available for each bike, both with stock and narrow racing pitch. By racing pitch, chain, rear and front sprocket are replaced with a bit more narrow components (with some exceptions where the pitch remains the same and only the chain is replaced with a lighter, smoother one), therefore transferring more power to the driving wheel (about 1-2 CV more, according to engine power), to the detriment of total duration of final transmission.
Tests on average duration proved that 30000-35000 Km can be covered by using stock lead with steel rear sprocket. With the same front sprocket and chain, but ergal rear sprocket, distance covered goes down to 20000-25000 Km, and using the narrow racing lead you can run 10000-15000 Km.