# won't run, misses, won't go over 38mph



## Hangingfor8 (Oct 3, 2009)

I'm haven issues with my 06 brute 750. I did a rebuild with new jugs, pistons, with the head gone through with new valves and springs. After I put the motor together, I added a snorkle, cleaned the carbs, retimed it. I can't get it to run good, If I really give it gas it bogs and it won't go over 38mph What do you all think? Timing? dirty carbs?


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## wood butcher (May 11, 2009)

try choking down the snorkle some with tape and see if it runs better and check ur chokes for sticking


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## DaBrute (Aug 16, 2009)

Did you rejet?


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## Hangingfor8 (Oct 3, 2009)

no, I haven't rejetted, It sounds like it's running rich


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## drtj (May 3, 2009)

Need smaller jets


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## Hangingfor8 (Oct 3, 2009)

is it common to need smaller jets after snorkling?


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## Yesterday (Jan 2, 2009)

did you use a 3 inch rubber 90* elbow when you snorkeled your airbox


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## RDs Neighbor (Jun 24, 2009)

It can go both ways. In all of my research (please don't take that as me speaking as an expert) most have to jet down after snorkeling. It is like breathing though a straw. It limits the amount of air flow in. 

Now with that said, this all depends on the size pipe and fittings you used. If you used 2" all the way, you most probably are running rich, and need to jet down. The current MIMB setup suggest 2" piping with a 3" rubber elbow exiting the air box. The 3" setup has allowed most to get away without re-jetting at all.

I used the 3" method with 2" piping, and I can't seem to get enough fuel to it. It leaned my bike out like you wouldn't believe. It has been six months and I am still monkeying around with it. It is real close though.

Moral of the story, expect the unexpected.

My immediate advice would to be concentrate on the air fuel screw mixture, and the needle. The jets are from about 3/4 to WOT. I see a lot of guys get hung up on jet sizes and it doesn't matter on the low end of the fuel curve. I am not saying it's not important, I'm just saying don't put the cart before the horse. Get it running real good at the low and mid range of the fuel curve and then proceed to dialing in the perfect jet size.

IMHO

Good Luck :bigok:


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## DaBrute (Aug 16, 2009)

What he :haha:said


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## Hangingfor8 (Oct 3, 2009)

I used the 3" elbow and 2" pipe. It just seems to be running rich. I'm thinking of just taking to the local shop that deals with snorkles. But I want them to garantee it'll be right. Like that'll really happen =P


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## drtj (May 3, 2009)

Mine was when I snorked mine had to go down on the jets a few sizes. I think I'm running a 144/148


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## RDs Neighbor (Jun 24, 2009)

Hangingfor8 said:


> I used the 3" elbow and 2" pipe. It just seems to be running rich. I'm thinking of just taking to the local shop that deals with snorkles. But I want them to garantee it'll be right. Like that'll really happen =P


Man if you did all the work in your initial post, you can definitly handle getting the carbs correct. I would give it a try if I were you. You could hang your hat on the whole job. That is cool shiz there.:bigok:


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## Hangingfor8 (Oct 3, 2009)

RDs Neighbor, It's been a haul doing all this stuff. I'm more of a fab guy, but I went ahead an ordered the dynpjet kit. I guess I'll give it hell.


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## 650Brute (Dec 18, 2008)

drtj said:


> Mine was when I snorked mine had to go down on the jets a few sizes. I think I'm running a 144/148


 
138 F, 142 R


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## RDs Neighbor (Jun 24, 2009)

Hangingfor8 said:


> RDs Neighbor, It's been a haul doing all this stuff. I'm more of a fab guy, but I went ahead an ordered the dynpjet kit. I guess I'll give it hell.


Atta Boy...It ain't that bad, just don't put the plastics on untill you got it just right. It takes longer to get to the dang things than to work on um.

There is a 90* mechanical screw driver you can buy that makes adjusting the AF Screw easier. I forgot who was posting pictures of it. It's floating around on a couple of the threads here. I use the screwdiver tip holder with the flat blade tip installed from my battery drill to adjust the screw. You will have to let the engine cool in between adjustments though.

By the way. Seat the AF screw all the way down and scribe a line..... in line with the screw head so you have a reference to where you are when turning. I bought a little mechanics mirror to confirm how far I actually turned it. This will help from having to remove the carbs everytime you adjust it. 

Take care and good luck
Neighbor


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## brianmcc23 (Sep 28, 2009)

RDs Neighbor said:


> Atta Boy...It ain't that bad, just don't put the plastics on untill you got it just right. It takes longer to get to the dang things than to work on um.
> 
> There is a 90* mechanical screw driver you can buy that makes adjusting the AF Screw easier. I forgot who was posting pictures of it. It's floating around on a couple of the threads here. I use the screwdiver tip holder with the flat blade tip installed from my battery drill to adjust the screw. You will have to let the engine cool in between adjustments though.
> 
> ...


 
I have a quick question... When testing your air fuel setting do you need to have the air box and cover on? I know it runs with it off but is that too much air? I was messing with my Teryx one day and it will not run under load with that airbox cover off. 

Thanks. not trying to hijack your thread but figured while we was talking about airfuel settings I would throw it in.


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## RDs Neighbor (Jun 24, 2009)

Yes it needs to be on. As you stated, it is way to much air. It may idle like that but I doubt you go very far with it off.

Everything I am suggesting is to be done and then ridden with the final setup. Snorkel, air box lid etc. If further adjustment is needed, repeat the whole process. Do a plug chop. Hold the throttle at the postion you are testing and kill the engine. Read the plug. Paper Bag brown is great, dark is okay, grey is bad. Rememer rich is better than lean. There should be a song for this by now, LAAAAA idle to 1/4 is the AF screw, 1/4 to 3/4 is the needle position, and 3/4 to WOT is the jet and a partridge in a pear tree.

Good luck


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## Hangingfor8 (Oct 3, 2009)

my 0 to 3/8 seems to be perfect so I'm guessing I'll do the needle position and jets first. If that doesn't do it then I'll adjust the AF screw


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## RDs Neighbor (Jun 24, 2009)

You are most probably okay on the AF screw and shouldn't need to re-adjust it. 

Dyno jet will tell you put the clip on the 4th ring, you should probably start at the 3rd position. Probably 142F and 148R (that is if you are running a stock pipe) If you have an aftermarket high flow pipe it will probably be closer to Dyno Jet recommendations.

BTW all jet manufacturer sizes are different. There will be three different sizes for the same jet diameter, use the link below as a cross reference.

If the bike stats to backfire, move the needle up by lowering the eclip, and or go up in jets. Pay close attention to where you are in the throttle position when the problems start so you can adjust the proper circuit. 

Keep in mind, if you add a pipe later, you will probably have to do this all over again. But it is worth it.:bigok:

http://www.mudinmyblood.net/forum/showthread.php?t=116

Let us know how it turns out.


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## Hangingfor8 (Oct 3, 2009)

I have the Wileyco full stainless exhaust. It flows much better than stock.


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## Hangingfor8 (Oct 3, 2009)

*HELP!!! rejetted and still not right*

I snorkled my bike and I have a Wileyco full exhaust so I needed to rejet. I followed the jetting suggestion via the dynojet directions and I still can't get the machine to run right a full throttle. I used the 150 in the front carb and the 155 in the rear. I have my needle set on the first groove and the fuel mix screw at 2 turns out. Help guys I want my brute back!!!


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## Guarino113 (Oct 3, 2009)

have you talked to bootlegger? hes helping me with mine. he knows what hes talking bout.


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## hondarecoveryman (Feb 28, 2009)

:agreed: Bootlegger is all you need on jetting


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## BIGDIRT (Nov 14, 2009)

Did you jet kit come with the drill bit?


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## Hangingfor8 (Oct 3, 2009)

Yes it did come with a drill bit. I've got it running better, but I got a little surge/sputter in the top end. I'm not sure what thats about. Any idea???? It's really got me aggrovated. Last night I had to walk away from it for fear I might just torch the sob.


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## Hangingfor8 (Oct 3, 2009)

Help Please!!!


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## drtj (May 3, 2009)

Pm bootlegger he will get u back running right


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## Bootlegger (Dec 18, 2008)

Got your PM and returned it....I have been reading some now. Your Needles need to be on the 4th notch down from the top. Air screw 2.5 turns out....then we will work from there. I will PM you my number.


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## RDs Neighbor (Jun 24, 2009)

Be sure to make sure the foot on the plastic riser isn't covering the hole you drilled. You may have to snip one of them off to keep from blocking the hole. It doesn't sound like that is your problem, but the more you take it out the greater the chance it will happen. Look in the bottom of the slide everytime you put it together and make sure you see light cominging through the drilled holes. You could have everything set correctly and the bike will run like crap and that would probably be the culprit. It happened to me.


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## Hangingfor8 (Oct 3, 2009)

ok I'm goingback out to put it on the 4th notch and turn the air screw out to 2.5. I'll be sure to check that the new hole isn't covered as well. Thanks everyone.


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## Hangingfor8 (Oct 3, 2009)

I did as you said and put the needle on the 4th spot and adjust the fuel air screw to 2.5 turns out and it actually got worse and the idle seems to be really high. i tried to adjust it down, but its as low as it can go.


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## RDs Neighbor (Jun 24, 2009)

I take it that it is stumbling or falling on its face when you reach the top end by saying it is surging. That is a rich condition. Go down one size in jets and try it again. 

Do you have the idle tuned all of the way out? You do know that it is a seperate adjustment than than the A/F screw misture? I wouldn't worry about the idle right now, you can set it later.

How does it run from a dead stop to 1/4 throttle and from 1/4 up to about 3/4 throttle. 

If you are working with Bootlegger on the side let me know, I don't want to confuse the situation.

Have patience you'll get there.


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