High quality exhaust valves manufactured by G & S Valves - Head Size : 1.635" or 1.655", with standard Model 30/40 stem diameter : 3/8" and blank stem.
This is blank stem type valve, where customer cuts length and collet groove themselve - which is the most effective way of ensuring the correct valve length for your cambox (see Information Listing item at the start of the valve section for more information.
1.635"/1.655" head diameter are the most common sizes for 350cc Model 40 International exhaust valves. However, this is also a very useful valve if you happen to have an early CS1 and its valve seat diameter does not exceed 1.655" (which is a fractionally smaller diameter than the later OHV/ES2 valve - our Item 0678, which are often fitted as a substitute valve on Walter Moore CS1 engines) - because it is 3/8" diameter, and has a blank shaft - therefore it can be cut to whatever length is reqired for your early engine, and if fitting coil sprngs - can be cut with either a parallel type collet groove (i.e. most SOHC collet type) or tapered collet (as per most OHV and some early CS1 engines). We can supply correct dimensions for either collet type.
Note: we also sell 3/8" blank stem valves for 500cc SOHC models (i.e. 1.735"/1.750" head size) - our Item 0037A_1 or 0037A_2, which can also be considered for early Walter Moore CS1 models - so you can cut your own length/collet type - but these are often too large for the earlier CS1 engines. You can email us for more information or to consider optons if you have an earlier Walter Moore CS1 or later coil spring SOHC model.
Price is each.
This is a variable listing - with two valve types available - one with a fractionally smaller head size than the other, see listing detail for indvidual stock availability
Left blank at end, so these can be cut to the same length as your original, and then the collet groove machined afterwards. This is the best way to ensure that you will have a valve the correct length for your cambox and spacing between cambox and head, particularly important if you are replacing a valve with a more obscure length.
This type requires you undertake the final cutting to length yourself (we used to offer this service, but the cost of setting up a CNC machine for a single valve collet is prohibitvie)
The last picture for this listing gives the collet groove dimensions - as are performed by G&S on the 'sized' valves, so you can machine these valves to the correct dimensions (we can also provide dimensions if you wish to cut the valve for a tapered collet - as per 3/8" OHV valves, and some early CS1 models).