no go after 5k rpm????

[KJShover]

The key thing is to change one thing at a time. that way we can eliminate things easier. What size jets do you have in there now and more importantly what do your plugs look like. They should be a nice tan color.

If your running a stock exhaust and no jet kit. I'm thinking putting your Vboost back to normal will help fix the flat spot.

 

[65fury]

The key thing is to change one thing at a time. that way we can eliminate things easier. What size jets do you have in there now and more importantly what do your plugs look like. They should be a nice tan color.

If your running a stock exhaust and no jet kit. I'm thinking putting your Vboost back to normal will help fix the flat spot.

Im not postive about the jets, but my needles are stock and the bike ran great before i cleaned the carbs, i put the vboost back on and i think it helped:confused2: but i still have a dead spot between 4-6k now it pulls hard to 4k and then sounds like its missing almost then after 6k it stats pulling hard again, if i WOT at 4k it stumbles, ill check the plugs in a minute and let you know. The exhaust is basically open headers... so no backpressure, im assuming this will lean it out? thanks

jason

 

[65fury]

Okay so i pulled the plugs and they all were a light tan color, sound about right? Should i try shimming my needles again(with thinner washers than before of course)???? i was told radio shack carries an assortment of washers... but i dont know what to ask for as far as the assortment pack? Also with the 4 2 1 kerker i was told it will richen my setup a little bit is that right? Thanks again, i know i have alot of questions but im taking a loooong trip August 18th and i need the bike to run right:clapping:

Jason

 

[[email protected]]

http://www.vmaxforum.net/showthread.php?t=1024&highlight=needle+test

Check out this thread. It explains the "needle test" and has some other useful carb tuning info. It should help determine wether or not you need to shim.

 

[65fury]

http://www.vmaxforum.net/showthread.php?t=1024&highlight=needle+test

Check out this thread. It explains the "needle test" and has some other useful carb tuning info. It should help determine wether or not you need to shim.

Thanks, ill try those tests tomarrow on my way to work, i did try the WOT at 4k and it stumbles bad....... can i try leaning it out by pulling the "Y" off? my needles are stock and cant be moved so how do i lean them out? Thanks

jason

 

[[email protected]]

Thanks, ill try those tests tomarrow on my way to work, i did try the WOT at 4k and it stumbles bad....... can i try leaning it out by pulling the "Y" off? my needles are stock and cant be moved so how do i lean them out? Thanks

jason

If its lean, it will feel kind of jerky. Almost like the bike has tourretes syndrome, LOL. If its rich, it will bog down but usually feels smooth.

 

[KJShover]

Okay so i pulled the plugs and they all were a light tan color, sound about right? Should i try shimming my needles again(with thinner washers than before of course)???? i was told radio shack carries an assortment of washers... but i dont know what to ask for as far as the assortment pack? Also with the 4 2 1 kerker i was told it will richen my setup a little bit is that right? Thanks again, i know i have alot of questions but im taking a loooong trip August 18th and i need the bike to run right

Yeah, a system will richen you up a little. I went down in main size to a 150 and probably can get away with a 147.5 with my stock carbs.

Shoot me your address and I'll get the .4mm shims in the mail to you. have you taken out your shims?

You can lean out by going with a smaller main. But this sounds like a needle issue not a main jet.

 

[65fury]

Well im going to have to say its running rich then, cause it still pulls thru 4-6k but its boggy, no tourretes here:rofl_200:tomarrow ill get some better info for you guys, ill do a hard run shut it off and pull a plug and see how it looks. Also ill pull my main jets and see what they are. I should have paid closer attention when i cleaned the carbs:bang head::bang head:


Jason

 

[65fury]

Yeah, a system will richen you up a little. I went down in main size to a 150 and probably can get away with a 147.5 with my stock carbs.

Shoot me your address and I'll get the .4mm shims in the mail to you. have you taken out your shims?

You can lean out by going with a smaller main. But this sounds like a needle issue not a main jet.

Yup shims are out! im going to get a few different main jet sizes from my yamaha guy just to have on hand in case i need to do some jetting:biglaugh: When i get my kerker will removing the "Y" help lean things up? or should i lean things up with jetting?


jason

 

[KJShover]

Yup shims are out! im going to get a few different main jet sizes from my yamaha guy just to have on hand in case i need to do some jetting:biglaugh: When i get my kerker will removing the "Y" help lean things up? or should i lean things up with jetting?


jason

It all depends on the bike, some run fine without the Y, some don't. mine ran like ass without the Y. I put it back on and shimmed that puppy about 1/8-1/4" it runs just fine.

My setup with the Kerker is; carbs stock, needles shimmed .4mm, jets dropped to 150 mains.

 

[65fury]

It all depends on the bike, some run fine without the Y, some don't. mine ran like ass without the Y. I put it back on and shimmed that puppy about 1/8-1/4" it runs just fine.

My setup with the Kerker is; carbs stock, needles shimmed .4mm, jets dropped to 150 mains.

Well since your setup is basically like mine will be ill probably copy you and see how it runs:biglaugh: id like to get an assortment of jets... know of a good place to get them?

Jason

 

[KJShover]

Morley can probably hook you up as well as your local bike shops. or you can get them online at powersport 360 for $2.50 ea.
http://www.powersports360.com/eshop...mpaign=base&v_traceback=c0728_2336_f0729_1338

 

[jfeagins]

Yup, new fuel filter too!:biglaugh:

Is your fuel pump building proper pressure and not trying to run too much at first "key on"? If the fuel pump diaphrams are misplaced inside it, and pressure is low..........it would run out up high before it gave indications at lower RPM's.

Also, I thought the airbox Y HAD to be in place for an OEM set up to breath properly, albeit, I thought without it, the bike would stumble from idle up into the midrange (not at high RPM's).

Trying to cover all bases.

 

[65fury]

Is your fuel pump building proper pressure and not trying to run too much at first "key on"? If the fuel pump diaphrams are misplaced inside it, and pressure is low..........it would run out up high before it gave indications at lower RPM's.

Also, I thought the airbox Y HAD to be in place for an OEM set up to breath properly, albeit, I thought without it, the bike would stumble from idle up into the midrange (not at high RPM's).

Trying to cover all bases.

Well my top end is pulling fine now, just my midrange is flat, the "Y" was put back on and vboost reconnected, im going to resync the carbs tomarow to see how far out they are since i wasnt able sync them perfectly the first time(the tool i had was missing a vaccum line and it was kinda janky)

Jason

 

[65fury]

Well after going thru all the carbs again and cleaning them really good! i found i had 165 mains and my floats were off, so i put some 150s in and set the floats correctly, installed the kerker exhaust. All other jets are stock(i checked to make sure) shimmed the needles with a .04mm shim and syncd the carbs. Needles to say my midrange is still stumbling and my top end doesnt pull nearly as hard:bang head: So i pulled the shim and it ran horrible, so i put in my thicker shim(1mm) and it ran a little better than the .04 shim. But im still boggin at 4-6k range at WOT. If i slowly rev up to 5 or 6k in 1st gear (1/4-1/3 throttle)no stumbling, as soon as i go WOT it stumbles! I get popping in the exhaust when down shifting too. Also my exhaust temp coming out the muffler is cool, never seems to get hot or very warm... kinda smells rich too :confused2:im 3 turns out on my A/F screws. oh and my bottom end doesnt have the same power now either...? Sorry bout the long write, im just trying to cover all my bases:biglaugh:


Jason