Spark Plug Question

[bigd]

Having read some of the threads I'm not sure if I'm running the right spark plug, my engine is a T5 with a Malossi 172 kit fitted, the spark plug I have in at the minute is a NGK B9ES, most of my journeys would be less than half an hour around town with the odd couple of hours at weekends, I've attached a picture of the spark plug I removed. 

[bigd]

Cheers Gaz, I should of said the plug I removed was a Champion N4C.

[pxguru]

Way too rich if that was plug chopped from full throttle. Whats the carb and jetting?

[henri]

havent got my manuals to hand an cant remember as never run a t5 but i'm with gaz a b9 or champion equivalent (havent got my sparkplug equivalent lists either)seems too cold a plug for the use your doing , as pxguru asks was plug chopped or just pulled at home after cooling/idling n runnin on less than half throttle , the nose of center electrode should be rich tea biscuit brown,or as i like to think/say "if ya plugs golden so are you" ,works on bath plugs too, from where plug has got to temp an burnt off the deposits .
would of thought if ya mix was rich with a cold plug like that you'd get fouling/wet oily plug syndrome , not pleasant a disease but cure is easy ,new plug off right temp range ,i'd go down to a b8 or equivalent ,an see how it looks after a few miles ,takes bout 10-15 miles to get "true colour" on a new plug with the sort of riding ya doing, unless ya a "WOT" (wide open throttle) type of urban hooligan , then it takes me bout 4-5 on a warmed up scoot. H

cant be arsed to go upstairs to other puter i can load pictures on but got some piccys of my missus's plug i chopped this week ,will post in mornin an give ya a idea what your lookin for , ok ,h

[vespasco]

Yup! ^^^^^^^^^
Either the b8/w4 is too cold or your jetting is too rich
Too much oil is also a slim possibility
Or your cut the engine after idling....

[bigd]

The plug was taken out back home probably after idling, not 100% sure on carb and jetting, is there away to find out?

I have been putting a 40/1 mix in, on the advice of the seller.

[henri]

nah , 50/1 or 2% if ya metric ,all vespas are that, tho he might of jetted it to match more oil but i dont know why ya would, ya carb will have a little plaque with spaco n size on , shud be either 20/20 or 24/24 ,an ya jets are the brass screw heads in top of carb under filter ,littler 1 is pilot n bigger 1 is called ya stack, unscrew it an read off the numbers ,its in 3 parts ,top with screw head is air correcter ,middle with a few holes is atomiser prob a be3 or be5 ,an tip/bottom with 2 holes is main jet ,not sure on t5 ,memory says tad smaller but most 170-180cc px's run around 118 to 122 ,
could be wrong on numbers as thats px 1's memory is draggin up , also what exhaust ya runnin an drilled or standard filter makes a diff to jetting , H

[bigd]

Cheers H,

The exhaust is a Simonini Sports Exhaust and the air filter hasn't beed drilled.

[henri]

am a bit tipsy (oh ye) but if i remember will look in mornin but drunk memorys sayin simoni's a expansion chamber ,but then sober bits sayin not the sport 1 ,sorry will look in morn an check t5 specs aswell, but stand by my earlier soberer statement a hotter plug is needed , my spider/zen senses are tingling an by "the twitchin of my thumbs a halfords trip your way comes", until ya get right heat range plug in any plug chop/colour isnt going to tell much , got to give up now mate,sorry but eyes are crossin an so's my legs ,need the little/big boys room urgent , H

[henri]

from the t5 owners page a standard 1 runs a 112 main on pre mix be4 atomiser an 50/100 pilot with a 120 calibrater?,guess they mean a air correcter, a malossi 172cc runs a same calibrater? be4 atomiser ,125 main ,pilot 50/100 with standard filter, an 100/100 with drilled ,
gaz'es 110 main is for auto-lube 1's an the extra g on the carb must mean sumting but i aint got a clue what, prob that it runs a larger p200 filter in that larger airbox, stick "vespa t5 jetting" in google an thats what ya get,hope it helps , H

[bigd]

Thanks for the replies lads, I will order up some new sizes of plugs and report back.

[sime66]

I scanned back through this thread quickly - did you get an answer about how/where to check your jetting? How to plug chop properly?
Also, what about your leak? Any progress with identifying the source?

[henri]

_ this is the sort of colour ya lookin for ok , plug from my missus's cosa after a free-er filter n jetted like a px125e pre-mix ,not a proper plug chop just after the mot run an about 20-25 miles potterin round town , colours the rich tea golden brown , on nose n electrode , you can find plug colour charts online but most are for 4 strokes ,ya need to check against a 2 stroke one ,but reckon a lot off ya darkness on your plug will be coz of the extra oil , ok, sorry i didnt post this in morning as promised but life/hangover got in the way , hope it helps ya , h 

[pxguru]

Lovely looking plug

[vespasco]

Ah Henri..I got a great detail of your brickwall but not ya spark plug..!! its a bit blurry on my phone...
But from what I can see it looks good for max hp and quick jaunts around town.

Whats your guys views on the following...?
If that was on my fast-ish motor that ran long WOT quite often id prefer to see that a tad richer...with all the base ring just black, and a slightly darker chocolatey colour on the porcelain. And id try a slightly hotter plug or 1/2 mark down on an equivalent plug. Thats by looking at how black the electrode is and how black the 1st few threads of the plug...
Or am I being over cautious/talking out of my a*se?!

[rab]

That plug colour is exactly how mine is burning on the 112 main it was all biscuit colourd on the 110 main

[sime66]

The Plug Chopper's Biscuit Scale:

[henri]

its for the management to run round town doing her job on ,not totally happy with it just posted to give bigd a idea of what to look for , had to guess the jetting an it might be a bit lean as it runs well fast for a 125 , on way to mot up a 1/12 hill pulled 3rd at 45-47 on speedo , snatched 4th at a plateau an did last bit at 49-50 ,on otherside going down a 1/20 2/3rds throttle saw speedo nudge 62-64 , nxt day 2 up on flat half throttle saw a steady 52-54 ,
know these are speedo's n didnt believe em so noted rpm on tacho an not sure if i used right ratios for a cosa but maths says its only overeading by 3-5 mph tops, seems ok for a 125 ,an seems to have loads of bottom end torque compared to my px150e engine , no probs doin a hillstart on steepest road 1/4 2up ,pulled first straight into second an would of had 3rd but was at junction then ,
if was goin to be used on WOT or long runs wud probably richen up a jet size or 2 , just a shame its loads of work to make my px fit her cosa n vice versa , tho she is booked for a dragv race against a px200 on a sip2 pipe , just for giggles of course , H

[vespasco]

Bourbon biscuit for my set up!!!

[sime66]

You see – the biscuit scale in action.
Henri’s is a Rich Tea; I’m going to look at mine on Saturday.
I added the Oreo biscuit so BigD feels a bit better about his plug:

[vespasco]

Hahahahahaha!!
When im riding, mines a 2 sugars, strong brew, lots of milk.

[pxguru]

Sime66, The biscuit scale is just perfect
Mines a bit digestive on the tip and oreo ring at the base of the cone, just the way I like it. Taken in the services after about 20 mins on the motorway.

[vespasco]

That looks a lot more pleasing to the eye §)

[sime66]

Finally, for those that like to live dangerously, I've added the Arrowroot at the other extreme:

Reckon I'll be sticking to a safe digestive

[sime66]

Don't be silly! Everyone knows that a custard Cream would come between an Arrowroot and a Rich Tea.

[rab]

well between the arrow root and the oreo its actually a very good scale to go by if custard cream was added it should be pinned by admin

[sime66]

I can do a six-biscuit scale, if you think it would help.
I have my reservations though, because it's really only half a degree of scale, and it's best not to be dallying at that end of the scale anyway;
but OK, give me a moment or two..............................

[rab]

it gives a close enough guide that anybody can follow with ease and if they cant they should buy a push bike lol

[sime66]

The Plug Chopper's Six-Biscuit Scale:



I cannot accept responsibility for the misuse of this technical documentation.

PLEASE CHOP RESPONSIBLY

[vespasco]

From hence forth, ye shall be known as...
Sime6Biscuits