The tyre is too tight and we cannot get the tyre fitted over the Stopaflat tube.
Solution 1: Over-inflate the old tube for a day or two before trying to install. That will stretch the tire a little and make installation a bit easier.
Solution 2: Soften the Stopaflat inner tube in hot boiled water (NOT BOILING WATER) for not more than 1 minute. Install it right away after taking out of the water.
The tyre is too loose and there is a gap in between the Stopaflat tube and the tyre.
Solution: Cut-out the valve stem on the old inner tube, and pack that inner tube into the inside of the tire... BEFORE inserting the puncture-proof tube unit. Leaving the old, airless inner tube inside therefore filled-up some of the extra space remaining inside
Questions & Answers
I have recently installed one of your Stopaflat tubes in my three wheel mobility scooter on the 16 inch by 2,25 inch front wheel. Now there is a terrible side to side vibration at speeds over 10 km an hour, is this normal or do I now have some sort of wheel balance problem now. I noticed that when I received the product was zipp tied in a small box and slightly distorted the circular shape of the product, could this be the problem and will it eventually regain its shape or is it now permanently damaged because of the way it was packaged.
Unfortunately you have used the unmatching size of Stopaflat tube with the tyre. However, our largest size of 16" x 2.125 tube is still too small for your 16" x 2.25 tyre. In this case, it forms some space/gap between the tire and the tube. Also, the friction inside will start damaging the tube when riding. After a certain period of damage, the side by side vibration is being formed.
You should STOP using the damaged tube immediately. And in the future, you must get a matching size of tube for the wheel.
However, there are some tips that may be helpful for you.
1) No matter of any sizes of the solid inner tube. They must be placed in the tyre tightly (shouldn't be moved around)
2) If the space/gap is formed even with matching sizes (tyre/tube). You may use the old (pneumatic) inner tube as a "SPACER", the method as below:
Cut-out the valve stem on the old inner tube, and pack that inner tube into the inside of the tire... BEFORE inserting the puncture-proof tube unit. Leaving the old, airless inner tube inside therefore filled-up some of the extra space remaining inside.