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Hey, new to the forum, not sure if this is the correct place for this, but I'm having some issues with my 06 brute.

Recently picked up a 750, ran amazing, and had tons of torque, but couldn't wheelie for the life of me, anyway, after doing some riding I figured it was a bit lean since it has an hmf slip on, and the valves needed an adjustment as well since it would pop out the exhaust when letting off the throttle, and backfire in reverse when the speed limiter was active, so I adjusted the valves and put a dynojet kit in as well as a wideband gauge.

It ran like ****

Wideband was reading max rich, over 10:1 and it wouldn't go over about 28 mph, and it barely had enough power to get out of its way, so I put all the stock stuff back in the carb but left the dynojet springs, didn't fix it, except when I get on the throttle, it's full rich then it kinda coughs and pulls like a bat outa hell and the wideband goes from 10:1 to 14.9:1 (at work)

so I put the stock springs back in, but that just made it worse, now it won't cough and go, now it just stays at 10:1 regardless of rpm or throttle, just 10:1 at 1/8 to full throttle, so rich it can't actually rev, even in neutral

I pulled the carbs all apart and cleaned them, even though I couldn't find anything wrong anywhere, not even dirt stuck in anything

I checked the chokes when I initially installed the dynojet kit, they weren't and haven't yet stuck, cables are free and the plungers move freely, but I decided to put stiffer springs in, so both seal (I tested) and basically can't stick in the bores

What do you guys think? Could adjusting the valves 180 out do this? Maybe a plugged exhaust? Or is it still something with my carbs?

Yes, filter is clean, no snorkel, belt is new ish, but no slippage, pink primary, stock secondary, moose module
 

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A couple of things that you have to make sure of is: that the choke plungers are in fact sealing. Even a twist in the cables can do that. That the valve last is correct on all valves. That the float levels are correct..and the A/F screws are no more then 2.75 turns out. 2.25-2.50 is normal. Did you drill the hole in the CV slide? If so are you sure they are in the correct positions? And I'm not sure about the main jet sizes. Should be 2-up from the stock sizes. Stock was 152/158 so..158/162 but if the float levels are high then that would be way too much and with a full exhaust system most will want the front and rear closer to the same so closer to the front's numbers. Also...make sure you don't have any larger slow or pilot jet then #40 . The #38 's were too lean with the Dynatec or Moose CDI but over #40 was a killer.
 

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A couple of things that you have to make sure of is: that the choke plungers are in fact sealing. Even a twist in the cables can do that. That the valve last is correct on all valves. That the float levels are correct..and the A/F screws are no more then 2.75 turns out. 2.25-2.50 is normal. Did you drill the hole in the CV slide? If so are you sure they are in the correct positions? And I'm not sure about the main jet sizes. Should be 2-up from the stock sizes. Stock was 152/158 so..158/162 but if the float levels are high then that would be way too much and with a full exhaust system most will want the front and rear closer to the same so closer to the front's numbers. Also...make sure you don't have any larger slow or pilot jet then #40 . The [URL=https://www.mudinmyblood.net/forum/usertag.php?do=list&action=hash&hash=38]#38 [/URL] 's were too lean with the Dynatec or Moose CDI but over #40 was a killer.

I'm op, just had to make a new account since the Facebook linked one wouldn't let me log in.

Yes, I drilled the hole in the CV slides, but I doubt that's the cause of the issue, but I might JB weld it if it would help

I've verified the chokes are sealing using a blowgun, no air would pass through with the choke level closed, the cables are straight and Free

Never touched the floats, and idle jet is still the stock #38 . A/f screw is about 2.5 turns out, idles at about 14.5 warmed up
 

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I'm op, just had to make a new account since the Facebook linked one wouldn't let me log in.

Yes, I drilled the hole in the CV slides, but I doubt that's the cause of the issue, but I might JB weld it if it would help

I've verified the chokes are sealing using a blowgun, no air would pass through with the choke level closed, the cables are straight and Free

Never touched the floats, and idle jet is still the stock #38 . A/f screw is about 2.5 turns out, idles at about 14.5 warmed up
The how about electrically? And battery or charging issues? 12 volts or better on the coils? Have you tested the pulse coil? Have you tied it with the gas cap loose...cause the tank vent check could be stuck.
 

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I'm op, just had to make a new account since the Facebook linked one wouldn't let me log in.

Yes, I drilled the hole in the CV slides, but I doubt that's the cause of the issue, but I might JB weld it if it would help

I've verified the chokes are sealing using a blowgun, no air would pass through with the choke level closed, the cables are straight and Free

Never touched the floats, and idle jet is still the stock #38 . A/f screw is about 2.5 turns out, idles at about 14.5 warmed up
The how about electrically? And battery or charging issues? 12 volts or better on the coils? Have you tested the pulse coil? Have you tied it with the gas cap loose...cause the tank vent check could be stuck.
Was no electrical problems before, it was always running well before I put the dynojet kit in, it ran like **** after putting it in, so put it all back to stock but that didn't fix it, haven't touched anything else.
How would a clogged tank vent cause it to run litterally as rich as it possibly can?

I'm still thinking it has to be the choke, but I don't see how, seeing as I've doubled the spring tension on them, and ensured they move free.

the little plastic boot thing that goes over the end of the cable where the springs seat is cracked where the bend is, but its still solid in there when the clamp is installed

Voltage is good, about 13ish at idle, battery fully charged
 

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Alright, did some digging, it seems the little brass jet thing in the tap that goes on the bottom of the diaphragm is missing, and because of that, the CV slide is staying shut at all times, how important is that brass jet thing? What can I do to go about fixing it? Besides buying a new CV slide
 

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Alright, did some digging, it seems the little brass jet thing in the tap that goes on the bottom of the diaphragm is missing, and because of that, the CV slide is staying shut at all times, how important is that brass jet thing? What can I do to go about fixing it? Besides buying a new CV slide
The vacuum that operates the slide comes through the hole or holes on the bottom of the slide and enters the top side of the diaphragm where it lifts it against the spring. That brass orifice has a hole much smaller then the holes in the slide to allow it to return by bleeding-off that vacuum. If missing, the hole is too large and the vacuum will not build up enough to raise the slide....so..you must have it. Usually you must get a new diaphragm or complete slide piece. PJ Motorsports may have it.
 

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Alright, did some digging, it seems the little brass jet thing in the tap that goes on the bottom of the diaphragm is missing, and because of that, the CV slide is staying shut at all times, how important is that brass jet thing? What can I do to go about fixing it? Besides buying a new CV slide
The vacuum that operates the slide comes through the hole or holes on the bottom of the slide and enters the top side of the diaphragm where it lifts it against the spring. That brass orifice has a hole much smaller then the holes in the slide to allow it to return by bleeding-off that vacuum. If missing, the hole is too large and the vacuum will not build up enough to raise the slide....so..you must have it. Usually you must get a new diaphragm or complete slide piece. PJ Motorsports may have it.
Figures, has anyone successfully got it working without it? If I was to restrict the hole by some other means, then is should still work right?
 

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Looks like most of the carb rebuild kits on Amazon have 2 of those little guys, I'll just go ahead and order a kit
Send a link because I can't seem to find one on Amazon for the CVKR-34. PJs also doesn't have a kit.
Ordered this one, cause it was cheap and it has those guys in the pic, though I'm pretty sure some of it will be incompatible, but that doesn't matter

https://www.amazon.ca/dp/B07TXWB8LF/ref=pe_3034960_233709270_TE_item
 

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Alright, got it all fixed now, replaced those tiny jets in the diaphragm, added the dynojet springs with 1 washer under the stock rods, and added dynojet 150/155 jets, and it runs better than its ever run before.

Hits 65 mph no problem, it's hard to keep the front end on the ground now!

Wideband is bang on, part throttle and idle are perfect, 14-15 at idle, and around 13-14 at part throttle cruise, and 11.8-12.5 at full throttle
 

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Alright, got it all fixed now, replaced those tiny jets in the diaphragm, added the dynojet springs with 1 washer under the stock rods, and added dynojet 150/155 jets, and it runs better than its ever run before.

Hits 65 mph no problem, it's hard to keep the front end on the ground now!

Wideband is bang on, part throttle and idle are perfect, 14-15 at idle, and around 13-14 at part throttle cruise, and 11.8-12.5 at full throttle

Good. Congrats!. Time to do some ride'n :)
 
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