Why replace a high rpm motor with a low one? 1. The high one was burned out. 2. The low one was much cheaper and stronger. The con is that it is heavier (without a centered motor, jumping is awkward)
Neighbor kid wanted to upgrade his trail ripper quad from the stock engine (50-100cc motor) to a 212cc engine. We cut out the suspension, spliced the area, and welded the suspension onto the back (with custom brackets). We had to disassemble and reassemble the shocks to do this so we didn't destroy them when welding.
Built a custom motor mount and sprocket. Runs well. I will have to get video of this at a later time.
"Delay Rock" Kevin MacLeod (incompetech.com)
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