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S3A constantly whiskering plugs??

Posted: Tue Oct 23, 2018 4:06 pm
by perfectpete
Hi there,

My recently rebuilt S3A is driving me crazy - one day she will run sweet as a nut and not miss a beat. Then, another day and she starts misfiring, so out with the relevant cylinder plug (it varies as to which cylinder!), and once cleaned up, she's running ok again!
I get roughly 30 or so miles of running before this happens - although it's not at the end of the run - it's the next day or so when the problem happens.
I have cleaned all electrical joints / earths throughout, and also replaced all points, condensers, coils and resent the gaps and timing.

I have also heard that Iridium plugs are good to stop the whiskering issue - anyone got experience of these?

Regards, Pete

Re: S3A constantly whiskering plugs??

Posted: Tue Oct 23, 2018 4:54 pm
by TF1
Iridium plugs made my h1 and h2 misfire and foul plugs

Re: S3A constantly whiskering plugs??

Posted: Tue Oct 23, 2018 5:31 pm
by SAM
Duff ngk?

Re: S3A constantly whiskering plugs??

Posted: Tue Oct 23, 2018 5:42 pm
by mraxl
Some things to consider....
-plug gap
-carb tuning
-2T oil
-B8HS plugs
-Don't baby it... run to red line a few times when ever you're out

Re: S3A constantly whiskering plugs??

Posted: Tue Oct 23, 2018 6:04 pm
by SAM
B8hs. Unless your racing!

Re: S3A constantly whiskering plugs??

Posted: Wed Oct 24, 2018 6:42 am
by perfectpete
Thanks all for the feedback!
Interesting - i have been running B9hs plugs since the engine rebuild (at the suggestion of the rebuilder), and plan to convert to standard B8hs after another 100 miles or so of running in - so let's hope this improves matters.
I am also going to get my carb's 'Tango'd' shortly, so i am sure this can do nothing but improve matters!

Regards, Pete

Re: S3A constantly whiskering plugs??

Posted: Wed Oct 24, 2018 7:20 am
by Wolfie
B9s or B8s should be fine, but where did you buy them?

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 7:29 am
by perfectpete
Hi Wolfie

I bought them off the internet - surely an NGK plug is an NGK plug wherever it comes from - or is it??

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 7:41 am
by Wolfie
Oh no definitely not.. the market was flooded with cheap chinky copies some years back, only buy them from your local bike shop.

I'll put money on that solving your problem..
Thumbs Up

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 8:17 am
by SAM
Wolfie wrote:Oh no definitely not.. the market was flooded with cheap chinky copies some years back, only buy them from your local bike shop.

I'll put money on that solving your problem..
Thumbs Up
Yep. They are everywhere!

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 8:52 am
by Nick64

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 4:16 pm
by Barrie
change your 2 strke oil

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 5:33 pm
by SAM
Ngk have big depot in hemel Hempstead! Might look by to see what they can do.

Re: S3A constantly whiskering plugs??

Posted: Thu Oct 25, 2018 7:41 pm
by Aardvark
I use Green Spark plug company for my NGK's.

I also use B8s plugs.

Touch wood so far no problems in six years.

Regards

Aardvark

Re: S3A constantly whiskering plugs??

Posted: Fri Oct 26, 2018 6:10 am
by perfectpete
Thanks all for the replies - i am stunned anyone would even bother to copy spark plugs, but there's modern life for you!
Will pop over to my local bike shop as suggested and start again with genuine new ones!

Incidentally, i am using Motul Technosynthese 2 stroke oil as recommended to me - any comments / advice on best oils to use (got a feeling i might have just kicked open a hornet's nest here with this question, but oh well??!!)

Regards, Pete

Re: S3A constantly whiskering plugs??

Posted: Fri Oct 26, 2018 7:35 am
by Wolfie
Gosh you must like burning yer money... :D :D

Try Carlube from Morrisons.. Thumbs Up

I don't know that stuff personally but these old motors don't burn hot enough for some modern synthetic oils and everything gets gummed up.

You could do a search of the site for 'Two stroke oil' and see how many times that hornets nest has been kicked..

Re: S3A constantly whiskering plugs??

Posted: Fri Oct 26, 2018 8:35 am
by SAM
As Graham says. Synthetic not a good idea. Mineral oil just fine. I buy 20 litres at a time. :D

Re: S3A constantly whiskering plugs??

Posted: Fri Oct 26, 2018 12:33 pm
by Doctorpayday
Gosh! how do you manage to close the seat down?

Doc

Re: S3A constantly whiskering plugs??

Posted: Fri Oct 26, 2018 1:34 pm
by SAM
Doctorpayday wrote:Gosh! how do you manage to close the seat down?

Doc
Problem it's a big container!

Re: S3A constantly whiskering plugs??

Posted: Fri Nov 02, 2018 8:57 am
by Neil the Don
Pretty sure your engine rebuilding would have suggested you run B8s while running in , then switch to B9s for full review riding.

And that Motul 1000 mineral oil is fine for that engine ?

Re: S3A constantly whiskering plugs??

Posted: Fri Nov 02, 2018 8:23 pm
by Mitsui Spy
I have been using Chinese NGKs (£16 for 20) and Asda mineral oil £5/litre in my 400 for years. Since I put it back to CDI from points it now runs fine on the plugs it fouled when it was on points. It gets caned everywhere and doesn't foul plugs or seize up.

A fouled plug says more about the ignition system than the plug.

A seizure says more about the way the bike is set up than the 2-stroke oil.

Re: S3A constantly whiskering plugs??

Posted: Sat Nov 03, 2018 5:26 pm
by gotz
Mitsui Spy wrote:I have been using Chinese NGKs (£16 for 20) and Asda mineral oil £5/litre in my 400 for years. Since I put it back to CDI from points it now runs fine on the plugs it fouled when it was on points. It gets caned everywhere and doesn't foul plugs or seize up.

A fouled plug says more about the ignition system than the plug.

A seizure says more about the way the bike is set up than the 2-stroke oil.
I totally support the above. Fouled up plugs can also be a result of riding habits....one of the many things my Dad taught me with a 2 stroke engine was ' to always work the throttle....don't always ride in the highest gear,.shift down now and then and let the motor rev ' .If my memory serves me right I only had 1 fouled spark plug and that was 1978.