RK Chain Kits

A chain kit brings together the chain, front sprocket and rear sprocket for your bike, and it is changed as a whole for a good reason: a new chain on worn sprockets soon wears out, and new sprockets with the old chain improve nothing. RK kits are made for a specific model and years and come in Standard, Reinforced and Racing 520 versions.

When it is due

• The chain has reached the end of its adjustment and the adjuster will not tighten it any further.
• There are stiff links that do not return to position, or rust that lubricant will not shift.
• The teeth of the front or rear sprocket are sharp or hooked, like a shark's fin.
• You hear noise or feel jerking when you open the throttle, or the tension varies depending on where on the wheel you measure it.

Pitch, teeth and final ratio

The chain number (420, 428, 520, 525, 530…) gives its pitch and width; chain, front sprocket and rear sprocket must share the same pitch, and each kit in this section already comes matched for its bike. The final ratio depends on the teeth: one more tooth on the front sprocket lengthens the gearing and the bike accelerates less; more teeth on the rear sprocket shorten it and the bike pulls harder, at the cost of higher revs on the road. The usual choice is to keep the standard ratio; if you want to change it, ask us on the chat before ordering.

Fitting and upkeep

It is done with the bike on a stand that leaves the rear wheel free. Tighten the front and rear sprocket nuts to the torque in the manual, set the chain tension to the slack your bike's maker specifies and align the wheel carefully. The joining link, if it is a rivet type, needs a specific tool; if you have no experience with the drive, it is a job for a workshop, because a badly closed chain is a hazard. Afterwards, lubricate it regularly and check its tension from time to time. To see the brand and its three versions, go to RK; and for other brands, to the brands directory.