Hi, i hope to get some tips from you guys. I wonder if i have to change my crank if i go for a 85 ccm polini cylinder? I have a 81 Vespa 50 Special.
If the crank is in perfect condition, there is no reason to replace it. Just make sure the con-rod is not bent, the endplay is within specs, and the roller bearing for the small end is good. This is enough for a daily driven scoot. But if you’re planning on racing, a good quality crank from malossi is your best bet. Hope this helps. Happy scootering and more horsepower.
Thanks for the help gileraboy, appreciate it:) This is as you say a daily driven scooter so it shouldn’t become a problem.
No problem, happy to help.[:)]