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Leftover Thrust Washer???

1771 Views 10 Replies 6 Participants Last post by  fastback50
Ever build something on your motorcycle and have this one little washer leftover? too. Dammit.
I have 4 super thin washers left over on my 1973 honda SL175. After rebuilding the top end (i didn't touch the bottom end), I put the bike together and ran it for about an hour. I then noticed these washers leftover on my bench. I have three theories: either (2)washers go on each side to the cam, they are spacers for the stator, or go somewhere on the end of the points case? Washer specs are: OD-22mm / ID-16.4mm/ Thick-.08mm.
Any help would be appreciated. I have pretty much built the entire bike from a pile of parts and this is the last gremlin i have to chase out.
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Here is an older pic of the bike...will post more recent ones soon.

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Maybe the spacers under the valve springs?
Looks like the thrust washer that control the end float on the cam shaft.
At least if it was a 350 there are parts that look identical and that is their purpose.
Thanks fellas...
I checked valve spring washers and found them too thick. I am thinkin that they must be thrust washers on cam...just don't know exactly where they go.
175's don't use thrust washers on the cam, washers on the valve seat b spring washer part# 14777235690 are 22 OD 15mm ID 1mm thick on the cb175. Only other thin washer on the topend I can think of is the one that sits behind the cam lobe on the spark advance that's approx the same OD and ID but about 0.1 mm thick and would be my guess but you wouldn't need 3

a couple of points I feel compelled to make on your build, to get the best out of your motor you should extend the headers so that they stop approximately where the original rear axle was, and add a couple of inches of radiator hose between the pod and carb, the 175's are intake and exhaust fussy. On a safety note the rear brake stay should be one piece not two pieces joined ( a single bit of flat bar will suffice )
Great post simo....that helped alot.
I am going to look behind the points case and I think you are correct that the washer goes back there. Also might explain the small oil leak.
The pic I posted is old and I have modified the exhaust with some baffles and a reducers on the end. I also rejetted the carbs so they work with the air filters. I have gotten it to run really well but might be robbing some horsepower from the motor so I will keep at it and see if the intake hose helps.
To be on the safe side I will bump up the flat bar thickness and ditch the old one. I got a new milol so I will make a nice custom one.
Thanks for the suggestions and great diagnosis. You rock buddy. Will post more pics and put togeth Dr a build thread when I get it back up and running.
If the you're leaking oil at the journal you'll need to replace the radial oil seal iirc it's a 8x 20 x 35
heres a picture of the advancer washer
You also might want to put the front fender mount on, as it is a fork brace also. You can leave the fender off, but the brace is important as the forks are pretty flexible. You should notice a little better handling.
I did put the front fender back on...that thing was a little twisty around corners without it.
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