This is the crankshaft bevel gear,, fitted to SOHC pre-Featherbed magnesium racing engines - i.e. M30/M40 and SOHC Manx type engines. These gears faithfully replicate the original Norton tooth profile and pattern and we have them made for us by a top specialist UK gear manufacturer.
Price is Each.
Because these have been made with the original (and correct) Norton bevel gear profile, they can be used in conjunction with original Norton lower vertical bevel gears (unlike some other pattern SOHC gears made in past years by others, that required they were always changed in pairs). However, if required, we also sell the corresponding lower vertical bevel gear (Item 0421).
Photograph 1 shows the gear from front and rear. Photograph 2 shows an original Norton gear at the top of the photograph and our gears underneath. Photograph 3 shows the International bevel gear on the left, with the shallower SOHC Manx gear on the right. The shallower gear was fitted to the magnesium crankcase racing engines - it being shallower, to allow for the Twin row timing side main bearing fitted to this type of engine. If you have an aluminium crankcase Internation or post 1930 CS1 model (with single row timing side main bearing - then we also sell the bevel gear for that engine as well - Item 0422
Final point - for anyone building a SOHC Norton engine for the first time - shimming the crankshaft and bevel gears is one of the most important tasks to undertake correctly to ensure it results in a reliable and healthy engine. Although not complex (compared to some modern engines), it needs to be undertaken in a specific order - and some elements of this process can be fiddly and time consuming . . . but it is definitely worth spending that time to get it right. If you are not sure how to do this (and what parts it helps to have to make this task more efficient), then email us on firstname.lastname@example.org and we will try and offer technical assistance