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Chopped monoblock on 650 SS PR bike

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I have not owned a 650 SS  before and the carb layout and details were a bit of a surprise. The chopped mono has some features all  of its own, Special jet holder, a brass insert into the bottom of the body and  special short screws to hold the cover on.Access to everything is a nightmare . I'm Hoping you guys can fill me in on any wrinkles  i need to know !.  The engine has been tuned at some time with polished ports and valve gear , not seen inside but presume there could be other mods.  It will be some time before i can run it . Its clear why the twin carb bikes are often converted to a single . The older 99SS twin  carb  layout was almost practical. I was not that bothered whether i got to ride this bike , just intending to show it. Now really curious as to how it will go. Perhaps it really is a racer , we shall see. Cam and ignition timing next.

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Not any more.  They were supposed to increase the gas speed for a better spread of power ,but not sure as i also understood that they were there to provide a heat path to avoid carb freezing. Something I have experienced on the 88 and 99 ,   Nortons were good at propaganda, so I think the freezing theory is the truth and the power story a cover. I wont be riding it in freezing weather. . 

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The sleeves are an oddity.  If they made sense for a 500cc 88SS, why were they also used on 650SS? Both have the same size carbs.  I wonder why?

The fittings for twin carbs use three studs and one Allen screw.  It's not possible to fit a nut on a final inner stud.

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The 650 is fighting me all the way.  I have realised that once converted to a racer I will be very limited in riding it due to old age, it also is very tight possibly from standing for years  or rough honing  and is not run in at all. If I am going to get it into a good fast reliable runner then its going to have to stay in standard form in order for me to get the miles in.I shall get it in proper running  order ,then re-style it. I keep finding pointers to a history on the track,  the swinging arm spindle  and nut have been drilled neatly down the threads for some sort of locking pin. Cam drive gears drilled ,lightened and polished. Going to check cam timings to see if standard SS. If not then different running clearances may be needed. Its a proper puzzle. A camera up its bum may reveal more surprises.

 



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