Apache speed problem. Please help.....

Hi there i really need some help. Ive finally got my sinnis apache on the road and on the way to the mot center there is a nation speed limit strip. Well cut a long story short i can only get about 45 mph out of it. I was wondering if there are any restrictions on them. I have a cone air filter and a performance exhaust on it. I am going to try a different jet in (a bigger one). If it is not that i dont know what it is. Has anyone else got anything else it could be if its not the jet.
Thanks for looking and will be great full for any advice. :confused1:

If you are running the stock 97.5 main jet that's probably the cause of the problem, buy a 105 and a 110 and try both of them. Also didn't you have a problem with your carb before? It could be blocked up or just faulty, if the bigger main jets don't work it might be easier to just replace it as you can get one for about £25.

Ok mate nice one thanks for your help again =)