Great downpipe, exhaust, and jet combo on a 92'?

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gavin.clennin

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Hey guys! New member here but have been reading these forums for years. I've had a 92' vmax for 4 years now. Had a guy retune my carbs about 3 years ago because I bought the bike from the west coast and I live in Colorado at 5,000'. A vmax veteran hopped on my bike and said it has about 65% of the power it should (so I'm guessing the dude didn't know what he was doing). I want to straight pipe it (4-1 or 4-2) and want a really good exhaust/ jet combo. I currently have a delkevic 4-2 and it's just too quiet. I want people to KNOW there's a vmax coming lol. Do I need to buy a chip aswell? Thanks in advance.
ALSO! I need a vmax mechanic in the Denver or Fort Collins area. Any leads would be amazing.
 
Welcome to the forum. There are lots of exhaust options. I have a full Mark's Performance Exhaust system with Sean Morley's jetting and air box kit. There are other jetting options but Sean's kit maximizes the mid range where most of us play vs top end. You can contact Mark's directly or Sean also sells his headers with different can options. You can't go wrong either way and doing business with Sean is the best buisness you'll ever do.
 
This is not a 'chip' bike, the ignition pre-dates that.

A 4/1 usually puts out maximum HP, where a 4/2 is capable of nearly as-much, but may favor the midrange a bit-more. Of course, it's all in the tune/jetting. Stock jetting for Mikuni sizes is usually mains at 152.5, see below. Leaning things out to 150 or 147.5 usually helps the CV carburetors, and there are other airflow jets to change. If you go to the Dynojet website, you can see the Stage 7 instructions, usually used best with a full header to canister (or canisters) exhaust, where the larger header pipes contribute to better flow.

Sean Morley can give you options about exhausts, but don't expect to see things change until you invest if the larger-diameter headers, and a free-flow (read, 'louder') canister or two. That requires jetting changes to get the best utility out of the system. If you go through the threads about carburetors, you will soon recognize which types of systems get mentioned frequently, and what tuning works, and what doesn't. Read-up a bit so you get a sense of what does work and what doesn't work. And if someone offers you a deal on some 'really-clean Cobra four-into-fours,' politely decline. You can read-why.

Copy this to your computer, you will be needing it. vmoa.net/VMX12-Service-Manual01.pdf I suggest printing out a copy, and putting it in a 3-ring binder. It takes some reading to get used to it, because the info on one part of the bike, may be shown in several different places, as it follows changes in different years' models. Torque values are found in the back.

VMax carburetor USA and CALIF..pngVMax carb complete.pngVMax carburetor.png
 
Here is a VooDoo it is a copy of the one's from Starrider performance . If you like it I suggest ordering from Mike he is good to deal with . I have several videos of different exhaust on my YouTube page Kyle Clegg. Stage 7 or Morley's Carb kits work great. I run kind of combination on mine it has stage 7 but still has the Vboost. voo doo exhaust - YouTube
 
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If your bike has 65% of power, you have some problems, which have nothing to do with new exhaust. If you replace pipes, this problem will not disappear. I guess 30-years old bike has many problems more important than pipes replacement.
 
If your bike has 65% of power, you have some problems, which have nothing to do with new exhaust. If you replace pipes, this problem will not disappear. I guess 30-years old bike has many problems more important than pipes replacement.
Yeah, there are definitely some boots and hoses that need replaced, but the bike is running extremely lean. No where near enough fuel. I just never knew the difference because this is the only vmax I've ever been on. I've already started the process of bringing it back to life but I figured I might as well put new pipes on it if I'm gonna be retuneing the carbs
 
This is not a 'chip' bike, the ignition pre-dates that.

A 4/1 usually puts out maximum HP, where a 4/2 is capable of nearly as-much, but may favor the midrange a bit-more. Of course, it's all in the tune/jetting. Stock jetting for Mikuni sizes is usually mains at 152.5, see below. Leaning things out to 150 or 147.5 usually helps the CV carburetors, and there are other airflow jets to change. If you go to the Dynojet website, you can see the Stage 7 instructions, usually used best with a full header to canister (or canisters) exhaust, where the larger header pipes contribute to better flow.

Sean Morley can give you options about exhausts, but don't expect to see things change until you invest if the larger-diameter headers, and a free-flow (read, 'louder') canister or two. That requires jetting changes to get the best utility out of the system. If you go through the threads about carburetors, you will soon recognize which types of systems get mentioned frequently, and what tuning works, and what doesn't. Read-up a bit so you get a sense of what does work and what doesn't work. And if someone offers you a deal on some 'really-clean Cobra four-into-fours,' politely decline. You can read-why.

Copy this to your computer, you will be needing it. vmoa.net/VMX12-Service-Manual01.pdf I suggest printing out a copy, and putting it in a 3-ring binder. It takes some reading to get used to it, because the info on one part of the bike, may be shown in several different places, as it follows changes in different years' models. Torque values are found in the back.

View attachment 79248View attachment 79249View attachment 79250
Thankyou for the reply! Quite the man of knowledge. With all due respect, I don't think I will be tackling any of the carb work myself. I can do a yfz 450 carb all day, but 4 on one motor, no thankyou. I will however, be downloading this and printing it out. Thankyou for your time
 
Yeah, there are definitely some boots and hoses that need replaced, but the bike is running extremely lean. No where near enough fuel. I just never knew the difference because this is the only vmax I've ever been on. I've already started the process of bringing it back to life but I figured I might as well put new pipes on it if I'm gonna be retuneing the carbs
Take a look at the Kerker 4-1 as well. Not as deep or "tame" as Mark's but that snarl......it sounds very pissed off.

Good luck.

Mark
 
Welcome to the forum. There are lots of exhaust options. I have a full Mark's Performance Exhaust system with Sean Morley's jetting and air box kit. There are other jetting options but Sean's kit maximizes the mid range where most of us play vs top end. You can contact Mark's directly or Sean also sells his headers with different can options. You can't go wrong either way and doing business with Sean is the best buisness you'll ever do.
Thankyou for the information! I think I'm really leaning towards a dragstar 4-1 slash cut muffler ceramic coated from srp. Thankyou for your time!
 
I have the Dragstar with a liter bike canister exhaust to make it much more quiet than the Dragstar screamer. I used the Dynojet stage 7 and despite what the stage 7 jet kit says about eliminating the V boost I kept the V boost. It makes it much easier to tune the carburetors for balance. I had to fabricate a short exhaust manifold to adapt the liter bike canister exhaust to the drag star pipe. I had the pipe expanded to the size I needed at a local muffler shop and then used a piece of flat Steel stock cut to size to weld the muffler shop piece to it. The Dragstar/cut or bologna cut muffler doesn't really muffle at all and you will need to use ear plugs. It is too loud for you to ride without ear plugs, don't even try it. My canister exhaust adapted from a liter sport bike is nice and quiet and while it's aesthetically a bit long it's very quiet and does not alert the local police that I am using the throttle. I also made a hanger bracket for the liter bike muffler. I use one of the barrel bolt clamps specifically for use in motorcycle exhausts rather than a common cheap hose clamp.
 
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I have the Dragstar with a liter bike canister exhaust to make it much more quiet than the Dragstar screamer. I used the Dynojet stage 7 and despite what the stage 7 jet kit says about eliminating the V boost I kept the V boost. It makes it much easier to tune the carburetors for balance. I had to fabricate a short exhaust manifold to adapt the liter bike canister exhaust to the drag star pipe. I had the pipe expanded to the size I needed at a local muffler shop and then used a piece of flat Steel stock cut to size to weld the muffler shop piece to it. The Dragstar/cut or bologna cut muffler doesn't really muffle at all and you will need to use ear plugs. It is too loud for you to ride without ear plugs, don't even try it. My canister exhaust adapted from a liter sport bike is nice and quiet and while it's aesthetically a bit long it's very quiet and does not alert the local police that I am using the throttle. I also made a hanger bracket for the liter bike muffler. I use one of the barrel bolt clamps specifically for use in motorcycle exhausts rather than a common cheap hose clamp.
That's the one thing I hate about all the Star Rider videos: they only barely blip the throttle so you really have no idea how loud it gets when you open it up a bit. They sound quite tame at idle, especially with the megaphone rather than the slash cut mufflers.
 

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