If the jubilee clips/clamps are getting tired on your Carb intake and air filter boots they can cause bad starting when the engine is warm and high idling etc.At the time of posting the Honda want £4/$8 each if you can find them.
I've found a better and cheaper option.
You can buy a Jubilee clip,"Kit" and make your own to the exact correct lengths you need.They come in the small width 8mm type(Which we need) and the standard 12mm types,
http://www.amazon.co.uk/NS-CT1691-Hose- ... B001MFX4TG
To get imperial sizes to match use this converter,
http://mdmetric.com/tech/cvtcht.htm
5/16" diameter should work.