Hi all,

Having managed to oil up NGK B6HS at a rate of roughly 1 per trial, would it do any harm trying a slightly hotter NGK B5HS? I won't be riding the bike on the road!

Does anyone else use these in their Cub?

Bruce.

could be worth a try, but think you realy need to sort the rings or valve guides to stop the oil getting in the chamber.if it,s a rebuilt motor, then maybe the rings need bedding in....or have you run it in too gently and the bore has glazed?

I had a similar problem on my B40, using 1 plug a trial, and also thought it was because it burnt a little oil.

But in reality I think it was more that it was running a bit rich. The oil smoke (I still have) is probably less that running a 2 stroke at 25:1, and plugs seemed to handle that ok.

I was using a plug per trial in my Ariel,then went from a B7 to a B5.Had no problems since having ridden it all summer without missing a beat.I just concluded that the plug was cleaning itself better as it was running hotter.It doesnt use oil or give blue or black smoke,so I think all must be well in the combustion chamber.

So on that basis,if its not smoking I'd try it.

Thanks for the response guys,

I purchased another B6HS and a B5HS to try today.

If it works, I'll let you know!

Bruce

I worked my way down from the recommended B7HS (2 sooty plugs per trial)to the BP4HS

The 4 is a 'hotter' plug

The P is for 'projected insulator' - gives a wider heat range

Never change the plug now, just gap it occasionaly

I worked my way down from the recommended B7HS (2 sooty plugs per trial)to the BP4HS

The 4 is a 'hotter' plug

The P is for 'projected insulator' - gives a wider heat range

Never change the plug now, just gap it occasionaly

A lot of locals use 4's in cubs. Last time i tried to order some from my supplier they said they were having trouble getting them so if you have some hang on to them. Seems to one to fit for Cubs.

have a look here for slightly more obscure plugs

http://www.gsparkplug.com/shop/