I have my 1979 shovelhead apart for inspection, it has S&S 4 1/4 flywheels, they are about 1/8 smaller diameter than stock, the clearance on the scraper is supposed to be .020. Has anyone else ran into this problem, if so how do you fix it? Weld a 1/8 piece of aluminum to the scraper? Talked to a machinist, he said to use a cold rolled low carbon shim and pin it to the inside of the motor and bend it to fit the scraper. I have also heard that without the scraper the flywheels throw too much oil on the rear cylinder and the oil ring can't keep up and it starts blowing oil out the rear exhaust and fouling the plug

 

you have no info about the bike for an answer

how is it you came to take it apart in the first place

was it smoking ?????

a fine line between too close the scraper to the flywheel distance and not enough - i would stop asking people who are not versed in S&S flywheels like the tech guy from S&S you should be calling - call them with the wheels numbers

 

I would not " pin " anything in the crankcase it will eventually work lose and then the fun begins . Only way to tell what's going on is split the case and get the feeler gauges out so and find what the gap actually is . Back in the day with smaller dia. stroker wheels you would build up the scraper boss with weld then have it fly cut to the right dimensions and this took a competent knowledgeable shop it isn't a backyard fix .

How about some more specs on the motor like bore , ect. ???

 

Weld up the case than cut back the weld till you have your .020" It is done that way all the time!

 

you can also do as I have done-- take a piece of aluminum flat bar -- drill 4 holes 3/8 tig weld it to the scraper -- yes you still have to weld it.. saves a little time and excess heat -- then fit it to .020 -- since the flat bar is well flat you only need to smooth the 3/8th holes and bevel the edge
whats the number/letters on the wheels