Parts › VILLIERS 32A,37A TRIALS 17 TEETH ENGINE SPROCKET 9437/17 Image 1 of 2 Image 2 of 2 VILLIERS 32A,37A TRIALS 17 TEETH ENGINE SPROCKET 9437/17 £25.00 17 Tooth primary sprocket to replace the original 20 tooth sprocket. Brings Gearing down for trials use Quantity: Add To Cart Added! 17 Tooth primary sprocket to replace the original 20 tooth sprocket. Brings Gearing down for trials use