1985 new to me..dont feel like its at full power

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tweeter45

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All,
i got a 85 1200 vmax. i dont feel like its hitting its full power what can i check to see if its restricted CDI BOX check (how) or what other electrical component can i check. the vboost does the clicking and i notice a increase at 6000rpm. throttle responce is weak in low rpm's. I read some max's 4th cylinder has issues..? also whats the norm for idle RPM.

and insight would be great
 
Great video. The clicking sound is the fuel pump coming up to pressure. The vboost solenoid is distant as shown in the video. Almost like a whine.
 
Try bringing up to 6k 1st then wack it. You will feel it then.
If I get on it from real low in 1st , I don't notice it either.
It does rev fast to 10k if you don't watch it tho!
Like I've said before, I was expecting a "hit" like my SXF 450.
It doesn't do that.
Yes my vboost is functioning.
 
All,
i got a 85 1200 vmax. i dont feel like its hitting its full power what can i check to see if its restricted CDI BOX check (how) or what other electrical component can i check. the vboost does the clicking and i notice a increase at 6000rpm. throttle responce is weak in low rpm's. I read some max's 4th cylinder has issues..? also whats the norm for idle RPM.

and insight would be great

The TCI box usually works or it doesn't. One thing you can check is to make sure the hose is connected to the vacuum sensor controlling ignition advance. And that the other 3 manifold nipples have caps on them, and in good condition. A compression or leak down test will verify if any one cylinder has an issue.
 
The bike should rev quickly. You may have restricted/clogged PAJ 1's and PAJ 2's and maybe even obstructed main jets. The bike is old, it's probably been sitting for much of its life, it's not uncommon to have dirty carbs compromising the performance. There are many threads, including 'stickies' in the carb section that can help you to try and clean them, but if the problem persists, you need to remove them, disassemble them, and clean them, most-likely in carb soak solution, or an ultrasonic cleaner. Look at the banner ad on the site for 'dannymax's' carb service, and you'll also notice from reading any 'dirty carbs' threads other members' names get mentioned, (Sean) Morley's Muscle (banner ad) and CaptainKyle, all of whom can clean your carbs if you find they have problems and cannot do it yourself.

When you run it hard from a standing start, in 1st gear, and change to second, when it hits second, it should surge forward with authority, rev cleanly, and break nearly every speed limit there is by the time you hit 9000 rpm in second. This should only take several seconds as-in a 0-60 mph time of say, 3 seconds. If you are not an experienced rider, this is not something you should be doing! The VMax has in its unrestricted state about 74 ft. lbs. of torque. That's enough to make the front wheel pull off the ground in first or second gears, and to spin the rear tire freely, if you happen to be on a wet surface road, or sometimes on a dry road!

You said you hear the controller for the VBoost operating, you should be able to see the wires that open/close the VBoost move with the airbox off.

Idle rpm : 1000

What exhaust do you have? If you have a Cobra exhaust, typically four separate exhausts, it looks cool, but you're costing yourself 10% of your max HP. A stock VMax on a Dynojet dynamometer makes anywhere from 105-119 RWHP. That's a range, of course, well-documented by road tests over the years. So, let us say, your bike in stock condition made 109 RWHP. The Cobra 4-into-4 exhaust will flow poorly-enough that your bike won't even be in triple digits for rear wheel horsepower! Since most people buy a VMax for its power characteristics, and the appearance, if you lean towards the 'appearance' side, the Cobras look cool. If you lean towards the 'performance' side, stay-away from them! If you have them, and you want to regain your HP, you will have to at-least replace the stock exhaust, or go with an aftermarket exhaust. Using the stock double-walled headpipes and slip-on exhausts from any number of manufacturers has been shown time and time-again to do nothing for adding RWHP. They just give you a different appearance, and are less-expensive to replace in the event of a spill.

Being in Canada, you might put out a request for someone close to you to take a look at it, and to give you an opinion on whether or not it's operating correctly.
 
The TCI box usually works or it doesn't. One thing you can check is to make sure the hose is connected to the vacuum sensor controlling ignition advance. And that the other 3 manifold nipples have caps on them, and in good condition. A compression or leak down test will verify if any one cylinder has an issue.

Where does it end up?
Under the tank or by the triple trees under the covers?
 
The bike is all stock except the starter, which i installed. where is the location of the
TDI box.
if i remove carbs and send out for total overhaul can they be synced at that time or do they have to be on the bike...this is my first mulit cylinder bike so i may have a few novice questions.

doesnt feel like a clutch problem but would that be a heaver spring or new plates to fix it?
 
The can be BENCH syncd off the bike, which will get them close. You basically use a thin wire.....etc, down the throat of the carbs to make certain that all of the butterflies are open the same amount. BUT, the best way, is on the bike.....with it running, also using a carb tool like a motion pro, or a morgan carb tune (which is better IMHO).

The TDI is on a little ledge just forward of the airbox. You will need to take the airbox off to get to it.

Has anyone told you about JIS screw drivers? Japanese Industry Standard. They will fit better(into what you THINK) is a phillips screw.
 
The can be BENCH syncd off the bike, which will get them close. You basically use a thin wire.....etc, down the throat of the carbs to make certain that all of the butterflies are open the same amount. BUT, the best way, is on the bike.....with it running, also using a carb tool like a motion pro, or a morgan carb tune (which is better IMHO).

The TDI is on a little ledge just forward of the airbox. You will need to take the airbox off to get to it.

Has anyone told you about JIS screw drivers? Japanese Industry Standard. They will fit better(into what you THINK) is a phillips screw.

Is this where the hose off #2 carb goes to?
My son told me about the special screwdriver.
 
Yes it goes to the map sensor used with the tdi.

Sent from my SM-G930R4 using Tapatalk
 

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