I have an older B3 Pro that was a hand me down from my brother.He gave it to me when I first started racing nitro.Its still an awesome motor.The first time I ran it was at our big spring race here in Ontario at Tillsonburg 2 years ago.Luckily before I tried to run it we noticed the carb was loose.We took it out and found a chunk broken out of the bottom of it,looks like someone my brother lent it too overtightened the pinch bolt.The peice of carb was still in the crank case so its a real good thing I didnt try to start it.We used some CA to hold it in and that lasted for 3 full race weekends before it came loose again.LOL.I now have another carb and pinch bolt to put on it and will keep it as a back up motor.I cant wait to try out a new B5.Hopefully I can get one before Motorama.