My cat is fine at motorway/cruising speed and high revs but when hot going slow on low throatle it runs jerky like its miss firing any ideas.

probably worn emulsion tubes.

probably worn emulsion tubes.

if so are they renewable

if so are they renewable

Yes they are, it might also be the carbs need balancing..(Syncing), this can also give snatchy performance at low throttle openings.

...Paul

My cat is fine at motorway/cruising speed and high revs but when hot going slow on low throatle it runs jerky like its miss firing any ideas.

Fuel vaporisation, hot day, hot engine, hot fuel, hot air, hot carbs.

My suzuki is a b4st4rd for it on hot days.

its more like when it warms up rather than hot hot