Another Carb question

[Fruteless]

I am going to be putting on a full fmf exhaust system on a 300ex for my brother and I was wondering if the needle has to be moved. The quad is all stock even the air filter. I am pretty sure the main jet should go to 128 and the pilot stays the same. I live in Pa if that makes a difference(the sea level position). Thanks!


Couldn't Find anthing under the search.

[Colby@C&DRacing]

the needle should be ok if you have a stock filter, Pilot does not have to be changed but it would start and run better in the cold with the next size larger pilot, To gain more from the pipe I would spend the money to get a high flow airfilter.

[Fruteless]

Would I need to jet differently if I put one in and when I jet it does the jet just screw in the whole way or where do I start.

[Bob-Hobo]

My 300 had a 125 main jet and it had a full system and filter. Plug was always brown too.

[Fruteless]

Man, you didn't even have to jet it. The dirt bike shop where I live wants to do it but they want $100 for the start. That's way too much and the other shop only does yamaha and won't touch it because it is a honda. Jetting doesn't sound that hard. I mess with alcohol rc cars. I think I can get it with some help.

[redrunner]

Pull up the servicehonda.com sight and get a schematic on the carb, then search for 300ex jetting here and you will get plenty of info. Just be careful not to strip out the slots, use a good flat screwdriver and push down when turning. If you do R/C's engines then moving the needle will be simple. As usual just keep track of how it comes apart.

[Fruteless]

You guys have been most helpful. The polls show that the setup of choice is a 40 pilot, 128 main, and drop the needle one on the e-clip. I went through all of the articles and no one topic dealt with this. So when I do this during the week I will post the results and have a close to definite answer. Thanks any other input and help is much appreciated. :p