Hey MO! I have a Bintelli Havoc 150cc and still can’t figure out which -B case gy6 engine I have, or if I even have a -B case engine in my scooter! Help! dmartin95
Yes, you are correct dmartin95. The BN157qmj has 54mm stud spacing, however, it loosely is considered a B case engine by some, but not by ScrappyDog. We call it the BN
The BN157 with extra long case (16″ wheel) has a standard A case cylinder, but has a taller head, and also has a slightly longer crankshaft. The variator and rollers are different also. This BN engine that is deviant typically has a -3 at the end of it. To confuse matter more, there is a BN157QMB (no -3) that was used in some scooters, like the Lance Duke, that uses 12″ wheels and is NOT a deviant -B. Parts for this variant are at the below link, and we are adding some more BN parts including complete engines which will arrive next week:
The engine we call a -B has 57mm stud spacing, which we sell as the gy6-200. The cylinder and head are different of course, but the crank and variator are overall the same enough to interchange. We sell stock, and even now performance parts for the larger case -B and these can be built out to 232cc’s. The gy6-200 is generally built to a beefier and high quality standard and also includes oil cooling:
Now we confuse things even more with the -B engines as there are some other deviant gy6’s out there, especially with ATV based engines, like Kazuma. Let’s not forget that QJ (Quingiang) has another variant engine which has a different cylinder and head, but not much different. We sell the QJ parts at the below link:
Hope this helps. MO!