so all the sudden yesterday it start to bog when i open the throttle; its still running fine but it now back fire sometimes and it sounds like its running on 2 cylinder; plus the gas smells like fuel.
Any idea what cause it? I have read up on the FPR problem, anyway to test it? I just don't want to start replacing thing before finding out the actual problem.
Thanks
Kit

 

Disconnect the vacuum line that connected to FPR, if you find fuel there, it's a good indicator that your FPR is due to be replaced.

If you haven't replace your FPR for a long time, it might be a good idea to replace it anyway since it is the second biggest problem for F4i (CCTL being the first one)

 

I was having the same issue (somewhat) with my bike. If its not the FPR, then the next thing it could be is the fuel filter inside the tank. My FPR was good when my bike was getting ****ty gas milage, backfiring on start up, exhaust was smelling like fuel, and I had slow revs too but the filter changed fixed it all. Of course, check the FPR first since its the most common and easiest to check

 

Thanks for the post; my symptoms are similar. New FPR will arrive tomorrow, but to change the filter did you have to change the whole fuel pump assembly, or was it just a replacement screen? I want to change mine, but I don't want to pay out the a** for a new pump. I have a hazy memory that the fuel filter is integrated into the pump.

 

I hope this can help you

https://cbrforum.com/forum/f4i-main-...sembly-146028/

 

Right, thanks for the reply; i have ordered a fuel filter and a injector unit(1/2 price compare to a new FPR in UK) so hopefully will swap it and see if thats the problem