Pazon B25ss igniition timing

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Pazon B25ss igniition timing

Post by *beezergeezer* »

Hi Guys/
I have just finished rebuilding a 1971 B25ss, I am running a +20" 10.1 piston original fitment..
I am also using a Pazon ignition and irridium plug BP8es equivalent...
i obviously realise due to today crap petrol i will get some pinking and use 10ml of octane booster per tank and 99octane fuel...
has anyone found and optimum ignition timing sweet spot, the book says 35 degrees and pazon say 37 degrees for B25, when i set it at 35 degrees it sounded like it was knocking, definitely not as all is set it to 37 degrees and it starts well but seems down on top end power (not carb as totally rebuilt slide jets etc)
so I am running at about 36 -36.5 degrees it pulls well but does seem to be a tad lumpy low down,
so like i say any of you out there found a sweet spot?
I am still running it in so any info will be appreciated..
Also i am running a standard oil pump the 3 stud version does anyone know if there are any aftermarket better ones out there? tried SRM but they don't do the 3 stud for B25ss ... sp=sharing

..see photo....Image
Jeff K
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Re: Pazon B25ss igniition timing

Post by Jeff K »

I would put a few miles on it and then start doing some plug readings. I have a old, large hand held 12v automotive exhaust gas meter that I like to use. Put the probe in the exhaust pipe and watch the needle. You would be surprise how many times the problem is not what you would think its is. Even though it carb has been has been rebuilt, do not rule it out as the problem. I would also use a timing light to check what the Pazon is doing at different rpm.
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Re: Pazon B25ss igniition timing

Post by beat »

good looking bike it is beezer

:thumb :thumb
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Re: Pazon B25ss igniition timing

Post by JB »

Very nice :grin:

Fairly certain the picture of your Beezer was taken around Gwithian/Godrevy area?

If you've got the later 3 stud iron pump then there's no real need to change to an SRM one in my opinion.

The adjustment of your front brake looks off to me! Because of the way the brake is designed, it's more efficient for the arms to be toeing out to each other than toeing in, although not as much of an issue with a B25 compared to the heavier bikes it was also fitted to.
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