Hi,

Please search on Youtube for "GSXR400 starting problems Part1-3". I have 3 videos posted;

1. Trying to start from rest
2. Started & idling, missfire can be heard when revving
3. Bike running normal after a quick ride.

Please view the videos & let me know what you think is the problem, I'm want to sell my bike & need to sort this out before.

Many thanks

pm sent

Already commented a few things it could be on the vid.
But best to get someone whos an expert with these.

sounds like compression issues from experience with these. They do seal better as they warm. usually caused from running with carbs with o ring problems for extended periods

stripes maybe right about the comp. If not some things to try- When you fitted the o'rings are the pilot ones fitted well/correct (o'ring,washer, spring then screw), possible air leak that gets better as the part expands, weak spark- ive had the pick up give a similar problem.