That’s interesting!
I probably won’t have the time nor the skills to try this approach though (the forum has been down for more than a month, and I still have a lot of work to do!).
After a first try, manually choosing keywords seems to have fairly good results, though I didn’t re-categorized yet and just played with SQL queries.
select title from topics
where category_id = 10
and lower(title) not like '%saddle%'
and lower(title) not like '%crank%'
and lower(title) not like '%pedal%'
and lower(title) not like '%rim%'
and lower(title) not like '%carbon%'
and lower(title) not like '%spoke%'
and lower(title) not like '%wheel%'
and lower(title) not like '%frame%'
and lower(title) not like '%hub%'
and lower(title) not like '%tubeless%'
and lower(title) not like '%disk%'
and lower(title) not like '%hydraulic%'
and lower(title) not like '%duro%'
and lower(title) not like '%dominator%'
and lower(title) not like '%torker%'
and lower(title) not like '%nimbus%'
and lower(title) not like '%bearing%'
and lower(title) not like '%pad%'
and lower(title) not like '%repair%'
and lower(title) not like '%handlebar%'
and lower(title) not like '%kh%'
and lower(title) not like '%kris holm%'
and lower(title) not like '%coker%'
and lower(title) not like '%tube%'
and lower(title) not like '%build%'
and lower(title) not like '%29er%'
and lower(title) not like '%36er%'
and lower(title) not like '%backwards%'
and lower(title) not like '%riding%'
and lower(title) not like '%foot%'
and lower(title) not like '%train%'
and lower(title) not like '%training%'
and lower(title) not like '%learn%'
and lower(title) not like '%learning%'
and lower(title) not like '%dismount%'
and lower(title) not like '%habit%'
and lower(title) not like '%idle%'
and lower(title) not like '%idling%'
and lower(title) not like '%freemount%'
and lower(title) not like '%free mount%'
and lower(title) not like '%free mounting%'
This query returns 33000 topics of 52000 from the main category that could be re-categorized. The number seems realistic, but I still probably need to add more keywords.
The method seems reliable enough.