183.5cc motor is alive

[Johnny 5]

I got the 62mm bore 60.8 stoke motor running, and it sounds good. Not able to test it in the dirt till next weekend. Going to make the breather on the valve cover a little bigger to reduce the crank case pressure.
Also going back to the 31 tooth sproket from the 39. with more power dont need to rev it out.
Jetted the carb from a 120 main to a 125 and the plug is coming out dark brown. Rich is good .
The compression is 155 psi after only 1 hour of run time. Starts a little slow but the battery is 2 years old. Stock compression was 125psi.
When testing power full throtle in the garage it would spin the tires and launch hard.
I will post a video soon.
I am so glad that it is running after all the money and time spent.
Hope it stays together for the season. I just dont know how hard you can push a gy6 until it blows due to heat and presure.
Thanks for all the help buggymasters.

[ckau]

Good job! You'll enjoy the new found power.
The motor spins over slower due to the higher compression. you may find yourself replacing starter clutches. There are heavy duty starter clutches out there that will handle the extra compression. You may have to cruise through the scooter sites to find one. Howett motors came stock with the HD clutch. I can't remember but I belive it was either the dunes or was it the tomberlines?, that came with howett motors.
An oil cooler would be that motor's best friend. The cooler is almost a must to keep the temps in check after such a upgrade.

[Johnny 5]

The start clutch is a 6 pin heavy duty one that came wiyh the motor. Some times even when the motor was stock it would take a second ignition cycle to start but always starts.
I am going to get a oil cooler before we go on our first 3 day desert trip next month.
I have the crankcase vent going into the oil seperator that was cut off the stock air box and into the home made intake tube for reducing back presure on the case fumes.
Going to install a little bigger vent tube in the valve cover and bigger vent hose to reduce case pressure.
Sent back the decompression tube vent when I thought about if the buggie tipped/rolled over all the hot oil would drain out and maybe catch fire.
We dont plan on rolling or flipping but I tipped my buggie on its side in soft sand and the first thing I could smell was gas from the cap vent dripping on the muffler.
I thank GOD it didnt catch fire and my seat belt released after several tries due to my weight on the seat belt latch. Tipped it back over and waited a couple minuets to restart it so the oil could drain back to the bottom.
Has anybody with a big bore stroker had any seal or gasket problems with the extra case presure due to the larger displacement?