ET: Engine (Twin) Plug Query

[brian gains]

Which is the less risky option regarding potential damage, running a hotter plug BP5, or dropping the needle a notch.
Rear cyl' seems to be running a little rich by plug appearance so I have gone to a NGK BP6 hoping the hotter plug would have better appearance but not much change with sooty appearance.
No problems with acceleration and fuel consumption is not alarming but I do get twitched about plugs fouling.

 

[Bill Thomas]

More like the slide too rich ??, That's where you are most of the time.

 

[greg brillus]

Try N5 C Champion plugs.........they seem to keep the electrode cleaner than NGK plugs.

 

[brian gains]

I do not do a lot of town riding so I thought that at speeds of 40mph + it would be the needle that comes into play.
I'll give the Champion a go.

 

[Albervin]

Is that 40 mph in 3rd or fourth gear? What slide do you have? Is the needle new? What position is it in now? How old are the jets? Only ever change one setting at a time.

 

[Gordon Ryley]

Hi Is a BP 6 the same as a BP 6 E I have tried all the usual permutations I could not get
these plugs for months ie BP6E I have read about them on our site in the past .
The Green Plug Co told me they did not stock them the classic car people like them.
months went by then they were in stock, with 8/1cr the starting & tick over is good
plug colour ok the twin & myself are getting older the bike is winning the battle.

 

[Chris Launders]

I spent some time last year setting up my 32mm concentrics on my twin, as I've always been rubbish at it a friend told me to mark off the relevant positions on the twistgrip for closed, 1/8th, 1/4, 3/4 and full throttle so I would know where I was in the carb's operation, I found at a steady 50 mph in 4th I was still on the slide !!!

 

[Bill Thomas]

Hello Gordon, As Brian has said BP5 and BP6 I would say yes,
B is 14mm thread,
P is Projected insulator,
6 is Heat range, About right for Vin's.

E looks like thread reach ? = 19mm which is as good as 3/4",
Have a read and see what you think,
I prefer Champion N9Yc, But that's another story .

Hope I am still Riding at your age ??, I have always started my Bikes sitting on them,
Unless they give trouble , But early this year I fitted a "D" centre stand, Not the handles just the stand,
To my Ex L/ning and I should have done it years ago, The stand has been in the Garage for years !,
And as I am getting older, I think it is more easy to give it a good kick on the stand ??.
All The Best, Bill.

 

[Bill Thomas]

https://www.vincentownersclub.co.uk/resources/some-information-on-spark-plugs-for-vincents.1380/