Stock YZ pipe
Posted September 07, 2005 - 08:12 AM
Posted September 07, 2005 - 11:07 AM
Posted September 07, 2005 - 11:13 AM
Posted September 07, 2005 - 03:20 PM
Without the insert it's pretty open and probably not that much different than the YZ in terms of flow.
I found that the YZ exhaust required a bigger main compared to the stocker completely uncorked. All things equal, when I put the YZ pipe on I had a terrible high end miss, which was cured with the re-jet. I also had a noticeable mid to high end boost. I think the YZ exhaust flows better.
Posted September 07, 2005 - 09:06 PM
I was wondering if I will need a jet kit on my 02 WR426 when i put a stock YZ pipe (slip on) on? My bike has the grey wire mod, twin air air filter, zip ty fuel screw, yz throttle stop, and that's pretty much it for the engine mods. It runs fine with an open wr pipe and a gyt-r insert. Will I need a jet kit? If so, which one is the best for the $$?
I have the same set up as you. With the free mods and stock un-corked pipe my bike ran pretty good with the stock jetting. After switching to the YZ pipe I soon realized the jetting was way off . I went with the JD kit because of all the recommendations on this site and I must say that I am very impressed . It is like a whole new bike. I couldn't be happier Just spend the money, you will be happy you did.