Sparkplug size help

Arterious /

Okie I need a new spark plug for my tomos a35 engine, I was about to go and buy the exact one in there but i decided to check online first what the standard tomos plug was and from what i've seen its different then mine?! Mines a b5hS and I've seen in 2 different places that had a different type listed, can anyone with an A35 engine please tell me what type of plug they have in theirs?

Re: Sparkplug size help

Reeperette /

Reccommended plugs

@ Champion = L82C/L86C/L90C (Depends on which book you check)

@ Bosch = W8AC

@ NGK = B5HS

? Motorcraft = AE4/AE4x/AE6 (depends on book)

# Denso = W16-FSU

? AC Delco = 422Z

# Splitfire = SF409C

? = Performance unknown.

@ = Known solid performer.

# = Not reccommended by me.

Plug gap should be 0.5mm in any case.


Re: Sparkplug size help

Arterious /

as always ree to the rescue =) thanks yet again, one more question, when should i replace the plug? is there a way to tell physicaly or just use it till it dies?

Re: Sparkplug size help

My hyosung says to clean or replace a plug at 3000 miles

Re: Sparkplug size help

I'd say I replace my Bosch about every 1200 miles or so.Don't have to,but Bosch supers are only 99 cents at Auto-Zone,so,why not?Keep the old one in the tool bag for a spare.I always put a little `never-seize' compound on the threads.One cold morning a while back,the Franco-Morini just didn't want to keep running when I first tried to start her.I just pulled the extra plug out of the tool bag and installed it and she fired right up and kept running.I'm thinking about trying a `Splitfire' plug because my brother says that's all he runs in his chainsaw and it makes a big difference.He cuts a lot of firewood with those Stihl saws of his so I tend to take what he says seriously.Any thoughts on `Splitfires' anyone?

Re: Sparkplug size help

bosch platinum. 'nuf said.


Reeperette /

I would avoid splitfire in a 50cc...the temperature change from a normal plug is a little radical when you only have one cylinder, and on a gadget known to be as 'finicky' as a moped.

You'd almost certainly have to re-do your mixture, and I did not believe it till the guy showed me the piston, but one moped owner had used one, and after a while it weakened the top of the piston dome and damaged it.

70cc kits now...I dunno, for all I know it might be helpful there...but I'd be leery of using one in a 50cc.


Re: Splitfire.Thanks,Ree!

I appreciate the warning.How about on the 60cc kit I've got coming?My brother only uses them in chain saws,and I know they run rich and have a totally different torque curve.I just normally put a lot of stock in Tom's advice concerning 2-cycles,but he doesn't know a thing about 50cc mopeds.

Re: Splitfire.Thanks,Ree!

everyone seems to hate splitfire plugs. so there must a reason. and i always recommend bosch platinum.

Re: Splitfire.Thanks,Ree!

Thanks,Miguel.I know you like platinum,and so do I.I'm always open-minded about spark plugs,though,`cause most are cheap enough to experiment with.To give you an example of why I am curious: My brother set the carb and sharpened my chainsaw the other day and it cut twice as fast! So when he says something it's like the `ol E.F. Hutton commercial;..I listen.But like I said,he doesn't work on mopeds.

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