Need advice

[jimbtn001]

new to pumping but i always end up with a doughnut i think its called.

[AndyJ]

The standard answer is "reduce the amount of vacuum and/or the amount of time in the tube."

But a big factor is often "tube too large in diameter." The closer the tube fits your erect shaft, the less room there is for the dog knot to form. You can still get a knot even with a tight tube, but it won't be as big.

Tubes commonly come in 1.75, 2, 2.25, and 2.5 inch outside diameters, or their metric equivalents. You may find it's cheaper to buy an inexpensive pump kit than it is to buy just a replacement tube.

(I always called it a 'dog knot' back in the day; I haven't got used to 'donut' yet...)

[sbelloten]

Agree with AndyJ

Reduce pressure and you will be as me to stay in the tube longer without a donut.