The Mountain Road could be closed for five weeks this summer for work to enable TT 2022 to take place.
Plans are in place to shut the route, in stages, between the 16 August and 19 September.
TT organisers say it's essential that a failing drainage system, in the Stella Maris and Barrule Park areas of Ramsey, is rectified before racing can take place again.
The first section to close would be the section between Barrule Park in Ramsey and the Bungalow.
This would be for two weeks with access from the northern villages and Ramsey via the Tholt-y-Will.
The next three weeks of work would see the stretch of road between the Creg Ny Baa and the Bungalow closed between 9am and 4pm.
The Department of Infrastructure says general maintenance will also be carried out including replacement of the centre and edge lines and new tram signals.
It claims delaying it beyond September would 'almost certainly' increase the duration of the works due to bad weather.
Minister Tim Baker said:
"The department acknowledges that this will be an inconvenience for many people but this work is necessary to allow next year's TT to go ahead as well as for safe long-term use.
"Nobody likes a road closure but repairs have to be done and this is the least worst option.
"I am not prepared to jeopardise the return of the TT in 2022 by failing to undertake this work now."
Consultation is now taking place with local businesses and Ramsey Town Commissioners.