Alan sent me pictures of a left Ace 100 case sitting beside a differing right Ace 100 case. The Left case comes from a pair which has a very high case number, P56648. The right case comes from a pair with the case number P42406.
The Ace B+ cases, according to Terry’s chart info, started with P58852. So even though they didn’t mount the cases in the bikes in numerical order, I would guess the P56648 would be in the Ace B range?
What I don’t understand is the thickness difference of where the cases meet the cylinder (see pics).
Was there a batch of motors which had both a thicker area where the studs screw in, and, a larger rear alignment dowel? When did this occur? But it still has the case part number 921001-02. Any explanations would be greatly appreciated.
In the top photo you see the ‘odd’ left case with a typical right case. In the lower photo you can see the enlarged alignment dowel. The hole in the alignment dowel appears larger than the hole for the kick shaft!
Thanks!
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