[dirty boy]

I have an 05 750 just put on a full hmf exhaust ,dyno jet kit and a dyna fs ignition jetted as per instructions with with dyno jet kit runs great but pops alot when i let off the gas sounds like it back fires a little is this normal. This is my first time tuneing a 4 stroke not used to the differance. thank you for any help u can give me.

 

[dirty boy]

forgot

o yea im running 150 f 155r in the dyno jet kit with stock air box and k&n

 

[Bigmike750]

What is your elevation? Also were are your idle mixture screw's set at?

 

[dirty boy]

oops forgot about that

screw is at 2.5 out from bottom needle forth down from non pointy side

 

[Bigmike750]

First check your exaust pipe's where they connect to the head's to make sure there not sucking air on deceleration,common problem on these brute's. If the headpipe's check out ok then you can usually tune out most of the poping with the idle mixture screw's. Try giving each one a 1/4 turn in or out. Try the 1/4 "out" first. It's basically trial and error until you figure out what the bike want's.

 

[denhambrute2009]

just a question... but as everyone says "trial and error".. do you have to put everything back together then find out somethings wrong then go back and take it all apart again??/... just wondering b/c i got my exaust in yesterday but it will be a week or so before i can start jetting and stuff

 

[Bigmike750]

Generally what I do is after doing a jet change or anything that deals with an adjustment on the carbs I leave the plastic side panel's off and ride it a few time's with them off. That way if you need to go back in and make another adjustment it's quicker to get to the carbs. Pretty much anything that I do that require's removing the plastic I'll at least ride it around for a few mile's before reinstalling it.

 

[denhambrute2009]

how hard is it to get to the carbs and stuff... i wish someone could post some pics or something b/c im clueless about these main jets and needles and what not!...lol.. i got plenty of people that can help me but i was just wondering so maybe i could try myself.

 

[Bigmike750]

Well, if you've never done any carb work or rejetting the Brute will make you an expert!

Their one of the most time consuming bikes I've ever had to work on as far as the carbs go! The first time I ever did one I thought "holy crap, I have a hundred bolts and screw's outta this thing and I still can't see the carbs!" It's pretty much pulling all the plastic off that's so time consuming.Once the plastic's off it's a piece of cake.

 

[dirty boy]

thanks

thanks for the help big mike

 

[Bigmike750]

No problem at all buddy, glad to help.