Successful 79cc engine swap on Motovox

#1
Hello, Been a while since I posted any progress on my projects and thought I would share another father/son project. Sometime last fall, my son's Motovox engine finally took a dump and we found a crack in the bottom of the engine casing. We already have another Motovox with the 212cc and know that would be too much for him so opted to try out the smaller engine from HF (79cc). This was a pretty straight forward install and we mounted it directly to the engine plate on center. There is an extra step on the install that is not on a typical 212 swap and that is to fabricate some type of throttle linkage. I took parts of the old linkage and blended them with the HF stuff in order to retain the governor. I also had to add an additional return spring because the linkage was not returning all the way to idle and although it works, does add a little bit of tension on the throttle which he found uncomfortable. I think I will just swap to a better set of grips and see if that helps. My son (age 11) also got his first experience on our lathe as he faced and parted off a new bushing for the chain tensioner due to the offset of the new engine. I also bent up a new clutch guard out of 16ga sheetmetal. Anyway attaching some pics and in a few moments when the video uploads I will post the link. The performance is definately a step up from the Motovox engine and I can feel some extra torque and speed but not so much that it makes the kid nervous (but enough to put a grin on his face). Enjoy-:thumbsup:



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https://www.youtube.com/watch?v=OBQWRr8SRBU&feature=youtu.be
 
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#2
Good stuff. This is what it's all about. I'm also in the process of putting one of those 79cc engines in a small frame for my 10 year old. Great work!
 
#4
Nice work !
We used a HF 79cc on my 8 year olds Azusa. I think that engine is perfect for a little kid. I had to buy mine when I was in Alabama and ship it home to myself. The 79cc is not available for sale in CA.
 
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