Hi Max,
Always possible , I put another carby on it yesterday, I have had the Honda motor sitting here for probably 5/6 years. The bloke I bought it off said the thought there was something wrong withe valves or cam. I never bothered looking at it till I decided to put this motor on this barrow setup because unlike all the other GXV's this one has a completely flat underside so it could sit on the plate with only a small hole for the shaft in it. When I started it up it was backfiring and would only run on full choke. Put another carby on it and it runs and starts first pull. Genuine Honda carbys seem to be able to sit for quite a while and start no problems it is the Chondas and Briggs that seem to have these problems with sitting. Anyway I will give it a start every so often, I seem to chase firewood at any time of the year or whenever some becomes available