woolleybac

Hi SK 400 Yes you are correct I am Birkin S3 ZA from South Africa and the Birkin factory is about 8 miles away. I have contacted Caterham but no reply yet, if it needs stripping I will do it myself to save a lot of time. I don't think its the problems you mention, this morning when I pushed the car out of the workshop the shaft was tight making the feel like the hand brake was on. I am sure its just a tolerance problem and mine only comes free when the outer aluminium casing gets hot. As aluminium expands more than steel this could be part of the reason its loose when hot? I don't know yet how many heat cycles it will have to go through to stay loose all the time. My next race is in two weeks at Kyalami race track, one thing is sure it will get hot Chris.

Hi there this is my first post on this site and I have the answer to SK400 question. My new box is doing the same as yours with 4th giving the most problem, I have found that its the 4th gear getting tight on the main shaft and some times when the clutch is pressed the gear stops/sticks on the shaft with the teeth not aligned so it will not engage 4th. If you double clutch and get the gears to spin again it will go into gear, this only happens as the box is warming up and by the time its hot it changes gear very well. I found going from 3rd to 4th it would not go in, I kept the clutch pressed and rolled to a stop. There was no way it would go in any gear, I could feel the syncro's trying to slow the main shaft and only when I let the clutch out in neutral to get the gears to spin would it engage gears again. I don't think there is damage taking place its just very hard to change gear until its up to operating temp. Good luck.