There were some 100's with the same stroke, but they all had real small bores , like 48mm.'s, like Parilla SS-21, Dap T91, ParillaTT25, TKM RL66. You would need to re-locate cyl studs. But why bother whan there are Reedjets out there at reasonable prices?
Why would you want too?.. if you want a 100cc, I have a reedjet I would swap for your sudam..
In answer to your question.. no.
You could do like jack suggests and turn a 1500.00 engine into a 400.00 engine, and good luck finding parts.. I have a couple tt25 topends if your dead set on doing it.. I don't know where you will find pistons..
Yes, 100 cc wet engines, they are formula "a" dd karts ran in euro.. same homolagation as the pcr tsl2k and 4 k's, vortex's, soniks, etc.. .. have run them as duals.. most of these engines come out of canada, and can be had for 4-500.00.
I don't think parilla made a tag sudam, they do make a wet parilla 125, as well as a aircooled tag engine.. if cheap enough, it should be a good candidate for a open build.. but forget about using on board starter it will never start it..
Too convert it too a 100cc would be alot more than just getting a 100cc. engine..
actually the EASYKART 125 uses the same internal parts as the SUDAM 125, they are the early Sudam 125 engines with the electric starter added, I have 3 of them and they are tons of fun, internally they are 3 port with the same exhaust and auxiliary ports as the sudam, the timing is a little more conservative and the compression ratio is lower, the carb is also a fixed jet HL348, I have one modified with the same head shape and porting as the sudam, same carb and exhaust and is as fast as the original, plus the starter which is a great convenience.
there is also a 100cc EASYKART TAG version, it bears nothing in common with the sudam, it is based in the TT75 engine
In theory Sudam stands for Sudamérica, which means South America in Spanish, so any builder that got involved in this specific SA class can have a Sudam engine, not only Parilla. Many European manufacturers didn´t build this engines other than during a few years that they made them for a FIA/CIK class later replaced by rotary valves 100cc, but some like Parilla, PCR and other did.