I just bought an hmf sport series slip on for my 400ex and i was wondering if i have to jet it or what ever?

 

I would highly recommend re jetting it. It will be runnin lean if you dont re jet it when you put the pipe on.

 

 

I am pretty sure that if you dont re jet it you will be rebuilding your motor fast because of how lean it will be running.

 

ok, i dont know anything about jetting and the muffler is the only thing i have custom on my 400ex. At hmfengineering.com, theres a basic kit, would that work?and if not how much would it cost me for what i need

 

I have the HMF utility series slip on for my rubicon, and I ordered it from www.worldwideperformance1.com and it came with jets, so I just took it to my local shop and had them install the muffler and jet kit that came with the muffler. I paid I think around $220 to get the muffler and jet kit shiped to my house then it was another $90 to get both installed on my rubicon.

 

Call HMF. they might know what size jet to put in. It should only cost around $90 to have it installed.

 

Call HMF they will tell you what size jet you need. Go to your local Honda dealer and buy your jet and a repair manuel for your 400EX. You'll save money and the manuel will come in handy in the future for making some repairs you can do yourself. Shops always charge a lot, even for something as simple as a jet change on your 400. I think if the throttle cable will allow it, loosen the clamps on each side of the carb, roll the carb over so you can get to the bowl. Remove the bowl, remove the float, don't loose the float pin, remove the jet and replace with the right one. Don't over tighten the jet. Put float and bowl back on, turn carb back down and tighten clamps, be sure to tighten clamps or you will suck dirt into the motor. I hope I helped. If throttle cable is too tight you might have to pull the fuel tank and carb, but try to find some way to get some slack in the cable first. Also I forgot to tell you to pull the drain plug on the bottom of the carb first to drain gas, be sure gas is off.

 

so i open the carb and put the stuff in and hmf will tell me the settings and i dont really need the most powerfull one, i just want to atleast make my quad run good and so i wont blow the engine or w/e and i dont want to spend too much money

 

Yes HMF should be able to tell you what size main let you need. Go to a local dealer get it or order it. Jets cost about 4 to 6 dollars and repair manual can cost 35.00 to 50.00, but you can use it to do small repairs in the future and save a lot of money. Then follow the directions above. You get to the main jet through the bottom of the carb. I tried to explain how I do it with removing the carb. Any more info I can help you with just ask and maybe some one else has abetter idea.