Your first message said Clashmore, and your correction said Clashnore.
I looked at the transcription on FreeCen, and John Gordon, aged 75, is in Clashnore.
I also looked through the entire enumeration district, and I don't think the households are in any sort of order at all - they are all muddled up, and don't look as if the enumerator has tried to follow any sort of route when collecting the schedules.
There are two households listed at Clashnore, two at Nether Clashmore, two at Clashmore, three at Nether Clashnore, one at Backside/Neither Clashmore and two at Backside.
The modern 1:25,000 map shows Clashnoir at NJ226219, Upper Clashnoir NJ223221, Nether Clashnoir NJ229224, Clashnoir Cottage NJ237222and Crofts of Clashnoir NJ238220. There is nowhere named Clashmore marked in this area.
The 1:10,560 map at www.old-maps.co.uk
shows the matching places, but spells them Clashnore rather than Clashnoir. So there is no doubt that what is listed as Clashnore in the 1841 census is the same as the modern Clashnoir.
I see that the 1841 census listing at Clashnore includes Jean Gordon, aged 60, and John, aged 33. The 1851 lists at Clashnore Jane Gordon, 70, and her son John, 43, described as insane. So this is obviously the same family.
In 1851 no places are listed as Clashmore, so all the ones spelled with an 'm' in 1841 are spelled with an 'n' in 1851.
To sum up, I am pretty certain that your John Gordon lived ast what is marked on modern maps as Clashnoir.