Vmax fuel issue...maybe

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Nah, it's the Cobras!

Don't even-bother loooking at anything until you replace the Cobras! Replacing the Cobras and returning the carbs to stock jetting will make that bike act like it's had another spark plug high-tension wire added. The VBoost will work! Sure, your choice, OEM, UFO, VooDoo, Mark's, Delkevic, Kerker, Marving, Supertrapp, anything but Cobras!

Yes, it's "that-big a deal."

you sound like you are 100 percent sure...is there a way to test your theory short of me buying something else. these Cobras look brand new and a new set aint cheap
 
I had put Cobra's on my bike after I got it & it never did that. It even had a stage 1 kit in it which I took out & put back to stock & it still didn't do that. got rid of the Cobra's & put on the Jardine cans it has now with my own baffles & end caps what a difference. Then dropped to 150 mains better yet.
 
why do people put Cobras on if their that shitty, I see them advertised for the Vmax
Purely looks and sound. Many people put stuff on their bikes due to looks, without doing some research and seeing that their new 'accessory' is hurting performance.

Lot's of cruiser guys do this also. They see what looks good, sounds good, and then 'gots to have it!'
And louder stuff to so many people makes them think of power and speed. But you can't deny dyno's, drag runs, and races to find what really works well.

Vinnie
 
I had put Cobra's on my bike after I got it & it never did that. It even had a stage 1 kit in it which I took out & put back to stock & it still didn't do that. got rid of the Cobra's & put on the Jardine cans it has now with my own baffles & end caps what a difference. Then dropped to 150 mains better yet.
See that’s the problem. I don’t know who owned it before the last guy and he sold it because it scared him after a week. I have no clue what the original owner did. I just know he took really good care of it and you know what a pain in the ass it is to take the carbs off
 
A Stage 1 Dynojet kit is not a good choice. Stage 7 is a good choice, or the Morley's Muscle kit [email protected]

The Stage 1 kit is problematic. Use the search function to have an hour's-worth of fun seeing how they are a poor choice for the VMax. However, the Dynojet Stage 7 kit, which needs a full aftermarket exhaust of proper design, and definitely not a Cobra 4 into 4 is a good one. I use a partial Stage 7 kit, I do not eliminate the VBoost; I have a UFO 4/1 with a custom canister exhaust.

Yes dropping 1 or 2 main jet sizes (150, 147.5 Mikuni) usually helps performance of a VMax. Dynojet main jet numbers are higher-numerically for an equivalent to Mikuni size. Use the search engine here to get that info for exact #'s.
 
A Stage 1 Dynojet kit is not a good choice. Stage 7 is a good choice, or the Morley's Muscle kit [email protected]

The Stage 1 kit is problematic. Use the search function to have an hour's-worth of fun seeing how they are a poor choice for the VMax. However, the Dynojet Stage 7 kit, which needs a full aftermarket exhaust of proper design, and definitely not a Cobra 4 into 4 is a good one.
So let’s say I wanna keep the Cobras. What’s my next step? And if I am going to change the exhaust, is Holeshot the way to go? I don’t wanna spend a grand. And I can’t tell you how pissed I would be if I did and had the same issue. Not at you of course cause you’re not the only one suggesting. Have you read some of the others
 
Here is what FIRE-MEDIC hates so much. I had a guy throw these in on my first vmax i got. Never put them on because there is no collector to the set up. Like they said it is 4 into 4 and i am not going from idol to wfo. to get down a strip of asphalt. BUT they ar shiny and pretty and i like to look at them and so does my dog.:rolleyes:
 

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I don't 'hate 'em,' I just think that if you're buying a performance icon, reducing the performance is antithetical to the bike's role in motorcycling. However, it's your bike so you get to do whatever you wish to it. If you like pretty, shiny things, like Gollum, in Lord of the Rings, the Cobras are maybe your choice.

I've ridden Cobra-equipped bikes, and the difference in performance was dramatic, compared to my stock-engined, UFO 4/1 exhaust bike. Just so you get this right, 'the difference in performance was dramatically-poorer!' VBoost didn't hit like a stock bike, the throttle response was soggy, with the exception of appearance, why would anyone bother?
 
I don't 'hate 'em,' I just think that if you're buying a performance icon, reducing the performance is antithetical to the bike's role in motorcycling. However, it's your bike so you get to do whatever you wish to it. If you like pretty, shiny things, like Gollum, in Lord of the Rings, the Cobras are maybe your choice.

I've ridden Cobra-equipped bikes, and the difference in performance was dramatic, compared to my stock-engined, UFO 4/1 exhaust bike. Just so you get this right, 'the difference in performance was dramatically-poorer!' VBoost didn't hit like a stock bike, the throttle response was soggy, with the exception of appearance, why would anyone bother?
So what do I wanna put on this beast then. Get the hole shots?
 
They're OK, you probably would be happy w/them.

Mark's is what many people have on their bikes, they like 'em.

To take advantage of the switch, a complete aftermarket exhaust and re-jetting is what you need. If you found a good used OEM exhaust, you still will achieve a significant gain in HP over what you have now. The complete aftermarket exhaust, with re-jetting is going to jump your HP even-more. From where you are now, it's not unexpected to end-up with a 20% gain in HP, assuming that now you're probably in the area of 90-95 RWHP with the Cobra 4/4's. A well-tuned Vmax with the jetting done and a good full exhaust can hit 120+ RWHP.

You might try contacting CaptainKyle [email protected] and Sean Morley [email protected] as they often have decent used parts.
 
They're OK, you probably would be happy w/them.

Mark's is what many people have on their bikes, they like 'em.

To take advantage of the switch, a complete aftermarket exhaust and re-jetting is what you need. If you found a good used OEM exhaust, you still will achieve a significant gain in HP over what you have now. The complete aftermarket exhaust, with re-jetting is going to jump your HP even-more. From where you are now, it's not unexpected to end-up with a 20% gain in HP, assuming that now you're probably in the area of 90-95 RWHP with the Cobra 4/4's. A well-tuned Vmax with the jetting done and a good full exhaust can hit 120+ RWHP.

You might try contacting CaptainKyle [email protected] and Sean Morley [email protected] as they often have decent used parts.
Yeah injust emailed Sean. I love the hole shots on my red bike but I might wanna try something else. See I don’t know if they rejetted these carbs or they are stock. I would assume they are stock due to the Cobra issue. Can’t know unless I take the carbs out
 
So what do I wanna put on this beast then. Get the hole shots?
Yes. Definitely. Stop posting, call them and they will tell you everything you need. They'll put it in one package for you, get your payment info, and that's that.
 
Yes. Definitely. Stop posting, call them and they will tell you everything you need. They'll put it in one package for you, get your payment info, and that's that.

but here’s my issue. I get it and it doesn’t fix it. That’s a $700 mistake. Unless I can sell the Cobras. They’re gorgeous
 
Someone always wants Cobras because of their appearance, set the price so they sell and they should. I'd start at 1/2 of retail, assuming they're almost-perfect.
 
If I were you I’d stop listening to everybody and find out whether or not you actually have a problem or you’re just experiencing a power loss from the cobras. Because if you have an actual problem your exhaust is not causing it so it’s not gonna go away.
 

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