What did you do to or for or with your Laverda today?

For triples the standard plug for low comp piston engines is B8ES.

High comp engines use B9ES.

A protruding tip may cause issues by glowing hot and causing pre-ignition.

I had an SFC 1000 come in with BP8ES as the owner said they were recommended by a reliable source.
I changed them to B9ES during the service.
I don't want to run the risk to go against factory specification

Looking forward to seeing Pop put back to standard. :o
 
There is a heat range and type for each engine configuration, after extensive work done by the manufacturer.
The engine in my bike is Corsa specification (compression ratio, valve and port sizes).

It also runs offset smaller diameter plugs as the head was repaired to solve cracks from plug holes across valve seats. The plug hole size was reduced and offset to minimise the chance of it happening again, but the spec is still as per B9ES.

The rest of the bike is irrelevant to this discussion, which is spark plug spec.
 
Not plug related but.....

Just finished work on a new seat for the Jota, originally supplied by a very nice chap on here and from way down under so very appreciative to him (bigthumb).

I wanted to give it a makeover before I fitted it as i can't leave anything alone :D and to bring it up to scratch, did take a bit of doing but that's part of the challenge and enjoyment of it all,and i'm happy with the results.
New cover from Tony at Eldorado.

























Just need to test it out now (bikebend) (bigthumb)
 
Went for 300 km ride through Tanunda, Nuriootpa, Koonunga, Kapunda and Eudunda ::)
 
Well, apart from being soothy (always), I just inserted these B9ES as they were told on here to be the correct plug heat grade for an SFC1000. I have used B8ES in my former RGS as well as my SFC1000 for decades with no melted pistons etc. so far.
But, better take the advice from the experts. So I bought a box of 10 B9ES and am now trying them out.
Apart from that, brass is new, gaskets, slides, jets, needles, floats are straight and set at 18mm, float forks are not too open, idle mix screws are new and set to 1,5 turn as recommended, though I just set them to 1 1/4 turn to try and lower soothyness, needle clip are at the middle notch, 60/2 slides, 265 atomiser, 118 main jet, 65 idle jet, acceleration pumps are installed and functioning well, all syncronised with my carbtune following procedures.
Standard paper air filter always clean fresh one, 2 * 40mm holes in bottom of airbox from factory, 40mm downpipes and 2 Jota end Cans.
Motowitt Mk 1 ignition, and I don't remember which curve right now, but it's standard.
Battery always charged fully and plenty of cranking amps. Schnabel voltage regulator as Nippo Denso burnt off like they always do.
cams are pretty spot on, so are valve clearance, primary chains and cam chain adjustment. Ignition pickups are original and adjusted to be pretty spot on.
Valve springs are Motodd 1/4 round less, same length. Bikes done 43000 km i total. Always fresh oil every 1500 kms and at least every year. No oil consumption ever. No smoke from anywhere.
Inlet tracts are swapped to 36mm aluminium ones and rubber connectors to carbs. Fits perfectly.
Carb top screw tight etc.
Choke plungers lubed at assembly and have a bit slack so they sit tight at the bottom position. Only ever use the chke function as a start aid device, around ? way and after 5-6 seconds off, just keeping gas a bit open while Warming up a Little bit.
Bike starts easy hot and Cold, and accelerates really well, strong pull from 1500 rpm to 8400. Smooth and calm stable idleing as well.
To prevent valve clearance distortion, I have always used Castrol Valmemaster + (ocatane version) plus used Shell Vpower 99. Tried anoter brand once for one tankfull, but same result.
Still soothy plugs.
Ggrrrrrr  ;(

Could it be a good idea to go smaller in idle jet size, say 62,5?

Lower needle (K1) to lowest position?

Can deceleration letting go of the gas roll make sothy plugs?

Any suggestions?

Kind regards,
Jacques
 
redfox said:
Well, apart from being soothy (always), I just inserted these B9ES as they were told on here to be the correct plug heat grade for an SFC1000. I have used B8ES in my former RGS as well as my SFC1000 for decades with no melted pistons etc. so far.
But, better take the advice from the experts. So I bought a box of 10 B9ES and am now trying them out.
Apart from that, brass is new, gaskets, slides, jets, needles, floats are straight and set at 18mm, float forks are not too open, idle mix screws are new and set to 1,5 turn as recommended, though I just set them to 1 1/4 turn to try and lower soothyness, needle clip are at the middle notch, 60/2 slides, 265 atomiser, 118 main jet, 65 idle jet, acceleration pumps are installed and functioning well, all syncronised with my carbtune following procedures.
Standard paper air filter always clean fresh one, 2 * 40mm holes in bottom of airbox from factory, 40mm downpipes and 2 Jota end Cans.
Motowitt Mk 1 ignition, and I don't remember which curve right now, but it's standard.
Battery always charged fully and plenty of cranking amps. Schnabel voltage regulator as Nippo Denso burnt off like they always do.
cams are pretty spot on, so are valve clearance, primary chains and cam chain adjustment. Ignition pickups are original and adjusted to be pretty spot on.
Valve springs are Motodd 1/4 round less, same length. Bikes done 43000 km i total. Always fresh oil every 1500 kms and at least every year. No oil consumption ever. No smoke from anywhere.
Inlet tracts are swapped to 36mm aluminium ones and rubber connectors to carbs. Fits perfectly.
Carb top screw tight etc.
Choke plungers lubed at assembly and have a bit slack so they sit tight at the bottom position. Only ever use the chke function as a start aid device, around ? way and after 5-6 seconds off, just keeping gas a bit open while Warming up a Little bit.
Bike starts easy hot and Cold, and accelerates really well, strong pull from 1500 rpm to 8400. Smooth and calm stable idleing as well.
To prevent valve clearance distortion, I have always used Castrol Valmemaster + (ocatane version) plus used Shell Vpower 99. Tried anoter brand once for one tankfull, but same result.
Still soothy plugs.
Ggrrrrrr  ;(

Could it be a good idea to go smaller in idle jet size, say 62,5?

Lower needle (K1) to lowest position?

Can deceleration letting go of the gas roll make sothy plugs?

Any suggestions?



Kind regards,
Jacques
Click to expand...

Are you doing plug chop after wot run or after popping up the corner shop ??
No harm in trying smaller pilot.
9's definitely won't clear up plugs as they are colder than 8's!
 
Grant said:
A protruding tip may cause issues by glowing hot and causing pre-ignition.
Click to expand...

Logic would indicate that if one NGK plug runs hotter than another it will have a different heat range number,  So I'd assume that BP8ES shouldn't get any hotter than B8ES.

Vince said:
It's not good to have any plug sticking out into the chamber ...
Click to expand...

I believe the reason for projecting plugs is to get the spark closer to the centre of the combustion chamber. Initiating the mixture burn as close as possible to the centre of the chamber is a good thing. So it's probably a sensible choice of plug for engines with low piston crowns. But if the piston crown is high enough to contact the plug's earth electrode, then the projection isn't a good idea. I've never measured piston/plug clearance in my Jota engine (with Hi-comp pistons) so I've not tried "P" type plugs. There's probably heaps of room in there though, so maybe I should give them a try.
 
Hooksey: I don't understand what you are saying. I am no natively English, so I don't get the meaning of the corner shop expression.

Anyway, I am thinking this:

* could Castrol Valvemaster+ add to the soothing?
*  maybe going to 62,5 sized pilot jets.
* can some type of spark plug caps make a weaker spark and inhibit propper burning of fuel mixture?

I have now filled up the tank with fresh Vpower 99 octane and will not add anything else for the tank full.
Waiting on sunshine. It's pouring Down outside right now, and Work is in the way ;)
My plan is now to inspect pickups positioning and advance if possible,  take a good run, get back home, and then take a look at the plugs.
Next is new spark plug caps.
Next is smaller pilot jets.
Next is another brand of fuel (OK just released 100 octane).
Next is a tank of 95.
Next is Castrol Valvemaster without the "+".

No, I don't test it with WOT and then a sudden off, then look at plugs, as I need it to run through town, idleing etc. without soothing in that condition too. Maybe I should do it, just to see if the standard #118 is too big? But strange it is. Carbs does not seem worn at all inside where the slide moves.

Kind regards,
Jacques


 
Jaq, pointless trying to read a plug and make adjustments to suit said plug unless done at wot ! Take a plug spanner out on the open Rd with you  ;) and work your way back from the main jet.
Too Mutch tootling around town on the pilot jet and no good for your highly strung Sfc think you need a 750 gt  8)
 
Oh, and it should be one of those ex-police arabian models...  ;)

All right, I'll give it some beans on the highway and break ignition, cool down and have a look.

Kind regards,
Jacques
 
It's much harder to read plugs with unleaded fuel, always burns with more soot.
Sooty plugs are maybe made worse using 98 unleaded plus Valvemaster additive. Not sure as I have never run it.

You have the SFC 1000, same engine as the Corsa, and the 65 pilots with 118 mains is the standard setting.

Personally I would not be guided by plug colour or sootiness these days, rather I would either set it up best I can by vacuum gauges, strobe etc or take it for a dyno run.
 
Paul Marx said:
Quite, forget plug readings with unleaded.
Use seat of pants.

Paul
Click to expand...

How often do you need to wash the pants to get the spark plug soot out?
 
Sooty plugs are maybe made worse using 98 unleaded plus Valvemaster additive. Not sure as I have never run it.


I use BP or Caltex 98 with a valve saver every 2nd or 3rd tank and NGK B7ES 32 thou gap in my S2 Jota. The plugs look good with a nice clean burn after a decent/long ride. eg not sooty.
Only time they get sooty is when I run it in the shed after its been sitting around for 4 or 5 weeks. = cold fouling?

The plugs are what was in the bike when I bought it from a reputable shop in Adelaide who had done the service before sale.
Don't no maybe its different here in Sth Oz, our tallest mountain is a little over 2,000 ft above sea level.
 
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