Not really, you do get the odd whiff.
To be fair though you only seem get that smell from 4 strokes I run my BSA B25 on Castrol R30 and it smells sweet, but my Greeves on R30 smells like most two strokes.
I
I had a similar problem on a KTM MX bike I had it welded then re-bored the spindle hole.
It never let me down, and it went off some big jumps!
(the welding cost me a fiver at a local welding specialist)
I agree with mclarke, I went to see if I could gets some parts from the autojumble
All the autojumble stands packed up at 2pm on the Saturday!
The trial was good, but you normally watch these for free.
Also Tesco are clean out of Bantam D14 engines! (probably had them b.o.g.o.f last week)
I would think you are safe with a BP6ES its just a slightly colder plug, I very the temp on my MX bikes according to the ambient temperature
With a colder plug the worst you will get is fouling
