Does the bike move with joggling? Do you often change the chain?

Maybe you will solve your problems with this product.

The transmission mechanism of a motorcycle is quite simple, made in most of the cases by two toothed wheels, one connected to the crankshaft (front sprocket) and one connected to the rear rim (rear sprocket), and by a chain, whose task is to transmit the rotary motion of the driving wheel, the front sprocket, to the driven wheel, which is the rear sprocket.

The front sprocket is never in axis with the swingarm pivot, except for some prototype motorcycles, so the overall length of the chain should change during the wheel travel, becoming maximum when the front sprocket, axle of the swingarm and rear sprocket are aligned.

This type of mechanism let the chain stretch at the moment of maximum extension, but it is not tense during the rest of the vertical movement of the wheel. Longer is the swingarm, less is the effetc at the same run of the rear suspension.

The fact that the chain is not always tense in the same way, generates some problems in term of regularity during the march. If the chain is not tense when we accelerate, the engine increases the number of revolutions and consequently the inertial effect relative to its rotating parts.

At first, due to the recover of the chain’s game, we feel a push on the wheel proportional to the increase in the number of revolutions of the engine, then, once the chain is completely taut, the whole engine torque is roughly transmitted to the rear wheel, giving us that whiplash effect that affects the driving pleasure.

Therefore, games too high on the chain give origin to little fluidity and a guide that is usually defined as “torn”.

On the other hand, excessive chain tension leads to a very high effort on the chain itself and on all the rear wheel and gearbox bearings. An exaggerated tension of the chain would bring it to stretch in a short time, requiring maintenance: moving the rear wheel of the bike, thanks to the registers that are present in every motorcycle, would consequently make the wheelbase longer than before.

This would make the bike less reactive and more difficult to ride, moreover, an excessive lengthening of the chain requires a replacement of the chain together with the rear sprocket and the front sprocket, which get damaged with the chain itself, requiring an expensive replacement in terms of time, work and materials.

To overcome all these problems and allow greater longevity to the chain, FreeSpirits offers you a dynamic chain tensioner, which aims to keep the chain always in light tension, so as to avoid sudden tears or irregularities during the ride, without overloading the wheel or gearbox bearings, or the chain itself.


This dynamic chain tensioner adapts itself to any condition of chain tension, thanks to a specially sized spring. It sets the goal of maintaining a constant tension, limiting its intervention when the chain is normally tensioned and intervening more decisively when the chain is too slack.

This chain tensioner is almost necessary for those who have mounted a riser system that raise the rear of the bike, because raising the rear, as explained above, change the moment of maximum tension. It is moved to a different moment of the travel of the rear suspension compared to the position of the original design, thus changing the tension of the chain during use.


This chain tensioner does not require maintenance, in fact, the lubricant of the chain is already sufficient to lubricate the sprocket wheel of the chain tensioner. You just have to mount it and enjoy immediately the result.

The kit is easy to install, it is complete of instructions and every change you make is reversible at any time, as FreeSpirits’s tradition.

The chain tensioner is compatible with the models:

  • Triumph Street Twin
  • Triumph Street Cup
  • Triumph Street Scrambler
  • Triumph Bonneville T100 since 2016
  • Triumph Bonneville T120


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