Istanbul Airport to Sabiha Gokcen Airport Bus Duration

The route from Istanbul Airport to Sabiha Gokcen Airport is generally a traffic free route. So If there is no problem, the duration from Istanbul Airport to to Sabiha Gokcen Airport may not exceed 90minutes(the route is around 85km) with bus. With taxi, it would not be more than 70-80minutes. But when you talk about Istanbul traffic, any generalization may be wrong. If there is an accident, a concert, a football match or even heavy rain on the route, it may take up to 3 hours. These are exceptions, but worth to take into account. So planning for the worse would be safer for you.