There was a problem, failures in the operation of the engine at high rpm, and pull from the bottom was perfect. Have docutel so 13 season. 14 when once again serviced the air filter, from Japan was installed. in place of the regular filter. Tried started without the top cover of the filter housing. Immediately there was a top, but bottoms gone. It was decided to add a parish of the air, cutting out extra holes in the lid of the box. Everything just fell into place, the lower classes remained, the top appeared. No more disadvantages.