Post by onewheeldrive on Apr 10, 2013 21:58:46 GMT -5
Here's a weird one. I tore my engine down yesterday--- been down for a few months, and I'm soon to be rebuilding it from top to bottom. It was running excellent, speed and power wise. I can't complain at all.
Anyway, I pulled the head off and saw what was a bigger piston than I expected. I'm actually not all that surprised, to be honest it was holding speed uphill much better than before, and I had more throttle to spare compared to previous equivalent speeds before. I basically thought to myself--- cool they sent me a 60cc engine, for the price of a brand new 50cc engine.
After I got everything, crank and all, tore down--- I decided to measure the piston with my calipers. It read about 1.
inches, and I went to the metric converter site and punched it the numbers--- now that is what surprised me! 47mm? It wasn't a 60cc top end, it was a 72cc(a.k.a 80cc). Nice. ;D
Now before I go on, I had to replace my top end and crank before--- but on my last engine, not this project/engine. I still had that piston, still attached to the crank in my garage. Now I wasn't sure if my calipers were off or what earlier, so I decided to measure that one. It was supposed to be a stock 50cc replacement top end--- well guess what now? It measured about 1.73 inches, equivalent to a 44mm piston----a.k.a 60cc!
Never even noticed it until now.
I still, yes STILL, wasn't sure if my calipers were just off or what---not the most expensive one. Well, I knew I had another piston laying around somewhere from way back, and sure enough it was the 39mm, I had 3 different pistons right in front of me.
I'm pretty sure I'll be ordering the 72cc top end. I'm very satisfied with the power.
Weird, huh?
Ordered a 50cc top end rebuild--- got a 60cc
Ordered a new 50cc engine---got one with a 72cc top end.
Anyway, I pulled the head off and saw what was a bigger piston than I expected. I'm actually not all that surprised, to be honest it was holding speed uphill much better than before, and I had more throttle to spare compared to previous equivalent speeds before. I basically thought to myself--- cool they sent me a 60cc engine, for the price of a brand new 50cc engine.
After I got everything, crank and all, tore down--- I decided to measure the piston with my calipers. It read about 1.
inches, and I went to the metric converter site and punched it the numbers--- now that is what surprised me! 47mm? It wasn't a 60cc top end, it was a 72cc(a.k.a 80cc). Nice. ;DNow before I go on, I had to replace my top end and crank before--- but on my last engine, not this project/engine. I still had that piston, still attached to the crank in my garage. Now I wasn't sure if my calipers were off or what earlier, so I decided to measure that one. It was supposed to be a stock 50cc replacement top end--- well guess what now? It measured about 1.73 inches, equivalent to a 44mm piston----a.k.a 60cc!
Never even noticed it until now.
I still, yes STILL, wasn't sure if my calipers were just off or what---not the most expensive one. Well, I knew I had another piston laying around somewhere from way back, and sure enough it was the 39mm, I had 3 different pistons right in front of me.
I'm pretty sure I'll be ordering the 72cc top end. I'm very satisfied with the power.
Weird, huh?
Ordered a 50cc top end rebuild--- got a 60cc
Ordered a new 50cc engine---got one with a 72cc top end.
