Bantam D1, D3, D5 & D7 - Original recommended plug:- Champion L7, L10, L82/C and L86/C. ) 0.500 inch (12.7 mm) reach.
- NGK recommended plug :- B6HS Stock No 4510 or Iridium BR6HIX Stock No 3419. )
Bantam D10, D13, D14, B175 and Bushman - Original recommended plug:- Champion N4. ) 0.750 inch (19.05 mm) reach.
- NGK recommended plug :- B7ES Stock No 1111 or Iridium BR7EIX Stock No 6664.)
Most Bantam Club members recommend the use of Iridium plugs to give good starting and excellent whisker free running. These plugs have a very fine centre electrode of only 0.024 inches (0.6 mm) diameter in rare and very hard Iridium material.
The stock no is useful when looking for a plug such as in Halfords as this number is printed on the end of the box. All plugs can be obtained cheaply on eBay as there are a number of sellers with postage as low as £0.50 whereas some have free postage but a higher plug price.
Recommended plug gap for all the above plugs:- 0.018 to 0.020 inches (0.45 to 0.55 mm).
When fitting a brand new plug, tighten by hand up to the sealing washer and then tighten a further 2/3 turn with the plug spanner. When re-fitting a used plug, tighten by hand up to the sealing washer and then tighten a further 1/12 turn with the plug spanner.
Thanks to Jubilee