Spinlock clutches and jammers

Spinlock clutches and jammers - How to select the right one?

It's not very easy to select the right clutch for your boat. The forces on the clutch depend on the type of boat you have, type of sail cloth, type of halyard and the way you sail your boat. A racer will always have a higher demand on his clutch then your average cruiser. Keep these points in mind when you select your Spinlock clutch:

Which diameter halyard do I need for my Spinlock clutch or jammer?

Every clutch had the most holding power at the maximum diameter. If you have a halyard of 8mm for example, please make sure your clutch is has a maximum size of 8mm. If not, you can change the cam to a size smaller with these kits. If your halyard starts to slip in the clutch it will wear up very quickly.

Rope cover in combination with aluminum or ceramic cam

The combination of rope cover and cam material is a critical one. Only the Spinlock Powerclutches XX come standard with a ceramic coated cam. We advise to use a rope with a Technora cover for these, as a polyester cover will wear out too fast. TN-Racing is a great halyard. A more economic solution is to splice a piece of TN-Cover over your halyard. All other Spinlock clutches have an aluminum cam and can deal with all covers. If you want to upgrade the grip, the XTS, XTR and XCS clutches can be upgraded to a ceramic cam.

Upgrade halyards from polyester to Dyneema^® core

We recommend having halyards with a core of HMPE fibres, such as Dyneema^® or Stirotex^® on your boat. Dyneema^® does not stretch and does great things to the performance of your sailing boat. When ever you are using polyester halyards your sails might start to sag in a puff which isn't great for the performance and fun of sailing. But if you use Dyneema® halyards all the forces will come down to your clutch, please keep this in mind when changing from polyester to Dyneema^®.

Do I need to inspect the cams of my Spinlock clutches?

Check your clutch at least once a year. Especially the cam because an old worn-out cam will cut your halyard pretty quickly. We sell Spinlock service kits with spare cams. Replacing the cam of a clutch is pretty easy.

How much force is there on my halyard or clutch?

On a windy day the loads on your clutch can become pretty high. How high depends on the type of boat, type of sails and type of halyard you have. There is a simple formula to calculate the loads on your clutch, however this formula is only an indication. Read more information on breaking loads on halyards and sheets here.

Formula: Maximum load = 30 x size of your sail*

* Use 13 x for a spinnaker