# wanna make sure I dont burn my brute up



## zillakilla (Nov 8, 2013)

I have a 07 750 that I just recently put a 2in snorkel on and k&n filter it seems to run great with out re jetting plugs look good and headers aren't glowing. I think I'm good but not really sure don't want to run it lean and burn it up.. any help would be appreciated going to put a hmf utility on it monday evening im sure ill have to re jet then. I'm new to the brute force's. But am pretty good with grizz 660s


----------



## NMKawierider (Apr 11, 2009)

The 2" snorkel would have richened it a bit over 5000 rpm. Under that there won't be much difference. Just watch the plugs after the HMF. That may lean it some.


----------



## D-LUX (Apr 14, 2013)

You'll know when you ride it... If you rev it up in neutral does it fall back to an idle quickly or does it seem to hang up there in the rpm range? 


/i\


----------



## parkerexpress (Sep 7, 2009)

I have a MIMB 2 inch on my 05 with stock exhaust. Been like that for two years. Runs like a champ and no issues (related that that anyway). I didn't put HMF on it mainly because I didn't want to get into re-jetting. Good luck, would like updates on how it goes. If you dont experience any major issues with the HMF I may try it out.


----------



## D-LUX (Apr 14, 2013)

Re-jetting the carbs really is not that bad.... Personally the hardest part about it is trying to get to the idle air mixture screw when they're still on the bike

I may do a step by step write up on jetting these things if there is not one here already


/i\


----------



## parkerexpress (Sep 7, 2009)

I havent seen a write up yet but would like too. I am still only moderately good at carbs, still have alot to learn and learned most stuff through messing them up...lol. Dont want to do that on the Brute so I have left it alone.


----------



## D-LUX (Apr 14, 2013)

I'll do one when I need to re jet after the big gun system I'm throwing on

Won't be for a few months though


/i\


----------



## zillakilla (Nov 8, 2013)

It runs like a top right now straight back down to idle. My brother had has a 06 with 2in snorkel k&n and hmf utility "same set up" and the guy that jetted his told him he has the biggest possible jets in and still has to run with choke on. I noticed the stock air in take hole measured 3 x 2 3/8 so figured id anything I'd have to jet down. I will be getting the pipe tomorrow and then im sure the fjn will start!!!

---------- Post added at 08:42 AM ---------- Previous post was at 08:40 AM ----------

Where is the idle mixture screw?? Is it under that little cap??


----------



## D-LUX (Apr 14, 2013)

Bottom of the carbs... Start at 2.5 turns out... 


/i\

---------- Post added at 02:03 PM ---------- Previous post was at 01:34 PM ----------

When you pull them do not separate the carbs... If you do you need to sync them again..

The rear will usually need a jet size up, it tends to run lean


/i\


----------



## zillakilla (Nov 8, 2013)

Ok thank you there is no screw on bottom of carbs just a metal cap where the screw should be.. looks like you have to drill it out????

---------- Post added at 05:45 PM ---------- Previous post was at 05:36 PM ----------

Ok thank you there is no screw on bottom of carbs just a metal cap where the screw should be.. looks like you have to drill it out????

---------- Post added at 05:46 PM ---------- Previous post was at 05:45 PM ----------

10/4 buddy ill check it out agian


----------



## D-LUX (Apr 14, 2013)

If they have never been touched you need to pull out that cover


/i\


----------



## zillakilla (Nov 8, 2013)

Thank you... nothings ever been touched I just bought it with 34 hrs and 150 miles on it. Got a smoking deal at 2 grand!!!


----------



## D-LUX (Apr 14, 2013)

Incase you didn't find the screw it is inside this boss that's circled


/i\


----------



## zillakilla (Nov 8, 2013)

I figured that's where it was just wasn't positive thank you


----------



## zillakilla (Nov 8, 2013)

Ok so is there va conversion chart some where in her to go from dyno jets to kelin jets


----------



## Polaris425 (Dec 16, 2004)

Yep. Under "Quick Links" at the top...

MudInMyBlood Forums Carb Jet Cross-Reference Chart


----------



## zillakilla (Nov 8, 2013)

Thank you. There's a lot of info on here but having a hard time finding what I need. Looks like after the hmf utility I put on today I'm going to have to jet it up. Plugs are running spotless and Rear header gets cherry hot after 10 seconds of idle. Bigger mains and some shims in my feuture.


----------



## zillakilla (Nov 8, 2013)

So I have tried 4 different jet combos and either running to rich backfiring out the exhaust or running lean and turning the back header cherry hot!!! Do you have to run a dynojet kit?? Its poping and back firing out the exhaust in the mid range

---------- Post added at 03:24 PM ---------- Previous post was at 03:20 PM ----------

Which means it's rich in the mid range you adjust the needle to fix that but cant drop needle down only up... ????


----------



## D-LUX (Apr 14, 2013)

Grab a dyno jet needle and drill the slides if you already haven't 


/i\


----------



## zillakilla (Nov 8, 2013)

Drill the slides????

---------- Post added at 06:10 PM ---------- Previous post was at 06:10 PM ----------

Ordered the kit today


----------



## D-LUX (Apr 14, 2013)

The dyno jet kit will give you specific instructions on where and what size hole to put into the slides helps a ton with throttle response


/i\


----------



## zillakilla (Nov 8, 2013)

Yes sir now we got throttle response!!! But still runs like crap.....


----------



## D-LUX (Apr 14, 2013)

what is it doing? to rich? to lean? does it lay over at high rpm pulls?

mid range is the hardest thing to tune for and if you have a dynatek cdi box its near impossible to get rid of the mid range miss


----------



## zillakilla (Nov 8, 2013)

The rear header is glowing for about a foot. Back firing when coming off throttle. Pulls like a SOB! Iv got the dyno kit in with 160f and 165r clip on 5. 2 turns out on af. The pipe glowing makes me think its lean. Runs worse with choke on.

---------- Post added at 04:43 PM ---------- Previous post was at 04:41 PM ----------

Can only run it for a 100 yard stretch but is still pulling hard at 41mph when I have to get off it


----------



## D-LUX (Apr 14, 2013)

Still lean on the back cylinder... Crazy that the head pipe glows that far out of the cylinder 

When you say the clips on the fifth slot, you mean on the top of the needle or towards the bottom


/i\


----------



## zillakilla (Nov 8, 2013)

Bottom...

---------- Post added at 05:33 PM ---------- Previous post was at 05:31 PM ----------

I'm ready to set it on fire!!!

---------- Post added at 05:37 PM ---------- Previous post was at 05:33 PM ----------

It gets hot enough it starts sparking like you have a torch on it


----------



## D-LUX (Apr 14, 2013)

Did you change the pilots as well? 

If it's that far down the needle step up the mains again for both


/i\

---------- Post added at 09:59 PM ---------- Previous post was at 09:51 PM ----------

Ok this may be going in the wrong direction if it's burning out the exhaust that bad... Have you ever adjusted the valves? Like the exhaust valve is hanging open...

When idling at operating temp does it smell rich? 

This is a reason I don't like the hmf slip ons, the rear head pipe is much larger and shorter than the front making it hard to tune


/i\


----------



## zillakilla (Nov 8, 2013)

The bike has 34 hrs on it.. haven't touched the valves. The bike ran awesome until i putt the snorkels filter and pipe on it a week ago has not been run since them except for 100 yard test runs. I have tried every needle and main jet set up I can think of


----------



## fatkidkustomz (Aug 27, 2011)

If it's running worse with the choke on, it might not be lean. It may be too rich. Open up your air box lid a little and see what it does. 

Sent from my SCH-I535 using Tapatalk


----------



## zillakilla (Nov 8, 2013)

Ok will give it a try here in about 20 min


----------



## dman66 (Feb 20, 2011)

Ditch the 2" intake snorkel,and go 3" intake


----------

