'92 Max dies after idle...

[Rayvin53]

Had the carbs off, there were no cracks obvious in any of the boots, but will try the 'spray method' next. With them off, I noticed on the forward head, just inward of the spark plug on the front right cylinder (is that cylinder 2?) a small tube sticking straight up from a circular plastic piece. Couldn't find it listed in the service manual, but is this supposed to have a hose on it? What is it?

 

[Rayvin53]

In using the service manual pdf, which model is my '92--the VMX12H, E, U, S or N?
Thanks.

 

[Rayvin53]

Forget the last post--found out the '92 is VMX1200D...

 

[maleko89]

Had the carbs off, there were no cracks obvious in any of the boots, but will try the 'spray method' next. With them off, I noticed on the forward head, just inward of the spark plug on the front right cylinder (is that cylinder 2?) a small tube sticking straight up from a circular plastic piece. Couldn't find it listed in the service manual, but is this supposed to have a hose on it? What is it?

That goes to your manifold vacuum pressure sensory. There should be a white piece in there. Make sure the arrow is pointed the write way. If you left that off it would run like crap.

 

[Akatora]

Hello, and welcome to the forum!

Have you tried with a new set of spark plugs? If they are dirty, it is possible that some cylinder(s) drop out at low rpm and the engine therefore stalls.


Regards,

AT

 

[Rayvin53]

That goes to your manifold vacuum pressure sensory. There should be a white piece in there. Make sure the arrow is pointed the write way. If you left that off it would run like crap.

I finally found the part in the service manual, it's the water jacket joint and what I thought was a tube is just a pin. I think I know what you're talking about, it's on the other side of the engine and the hose from the vacuum advance goes there, where on the other 3 carbs they have rubber caps on them...all used for carb synch. Is that what you thought I meant? Also, isn't the right side of the engine my right side if I'm sitting on the bike?

 

[Rayvin53]

Hello, and welcome to the forum!

Have you tried with a new set of spark plugs? If they are dirty, it is possible that some cylinder(s) drop out at low rpm and the engine therefore stalls.


Regards,

AT

Tnanks for the reply, AT. New plugs, air filter, fuel filter.

 

[maleko89]

I finally found the part in the service manual, it's the water jacket joint and what I thought was a tube is just a pin. I think I know what you're talking about, it's on the other side of the engine and the hose from the vacuum advance goes there, where on the other 3 carbs they have rubber caps on them...all used for carb synch. Is that what you thought I meant? Also, isn't the right side of the engine my right side if I'm sitting on the bike?

Yes, that's what I thought you meant.

Yes, left/right as sitting on the seat....as long as you're facing towards the handlebars.

 

[Rayvin53]

Here's the pics from the manual showing the part I was referring to, Mark.

 

[Rayvin53]

Did the 'spray the boots' method, no effect. I hate to say it, but with the bike running exactly the same way as when I bought it, despite the new parts and work I've done, I'm frustrated and about to give up and take it to the shop. Thanks to Mark, Shawn and everyone who tried to help me out with this.

 

[maleko89]

I wouldn't give up yet. How comfortable are you disassembling carbs? The bike is over 15 years old and am betting the carbs just need to be cleaned. I would get an estimate from the dealer on this. Otherwise, someone on this forum can do it too.

 

[Rayvin53]

Hey, solved my problem, 90% of it anyway. Was syncing the carbs just an hour ago, when I pulled off the rubber plugs to attach the manometer, one had a few major cracks in it. Synched the carbs, taped up the cracked plug, thing still needs a minor amount of choke not to stall (very minor amount), doesn't stall or hesitate on acceleration. I'm just glad not to be giving bucks to someone to get it fixed.
So my only problem now is to have it run without any choke on at all.
On my way to dealer to get a few things.
Oh yeah, thanks for the good instructions on the carb sync, Mark. I really appreciate all the help.
Vin

 

[maleko89]

Great! You can order 3 replacements for about $10. Set you idle a bit higher and if that doesn't take care of it starting running Seafoam in your tank. I would use about a shotglass full every other tank.

 

[Rayvin53]

Found that the pilot jets on all the carbs were completely closed off with a greenish crud, so I'm assuming that is at least part of the reason for the inability to run w/out the choke on. The hole in that thing is so damned small--is it for gas or air? Also, I used one strand of copper wire to clear the holes in that jet, just the right size, didn't have to force it through or anything. I've cleaned out every other jet on all the carbs, none of them were blocked. I'll check out the procedure on setting the float levels dry, reassemble everything and see how that all works out.

 

[Rayvin53]

What a difference a little hole makes...

Reassembled the totally cleaned carbs and clearing those pilot jets straightened the whole thing out. I can see how they can get blocked so easily, they're tiny.
Thanks again to Mark and everyone else for the support on this--now I'm putting on some gear and taking the beast for a late night flight...
Vin

 

[maleko89]

Great news!

Those PFJ holes are tiny aren't they? I always remove them from the jet block to clean. I have a little pixie straw to make sure I can blow threw them.

Let us know how your ride goes.....ride safe.

 

[Rayvin53]

success!

Good ride, the thing ran great, thanks. It's a '92, but has less than 20k miles on it and I picked it up for $2500, so now that it's running right I'm couldn't be happier. Halfway through the carb sync my manometer cracked (one of those motion pro mercury types), so I need your recommendation on a new one, non-mercury based. The questions never stop, do they?:ummm:
Even without the completed sync it was night and day. First time I'd taken the carbs completely apart, so I was thrilled just to have put them back together right (and with no extra springs or screws left either!).
Still have some new parts coming in--the carb to vboost boots, the 3 rubber vboost manifold plugs, mirrors, some new screws and bolts to replace rusty ones, etc. I do think I'm going to be looking at a small windshield, as funky as they usually look, since being used for a parachute on a long ride would quickly get tiring--wouldn't mind just getting some of the wind off my chest, don't need a barn door huge one. Still lots of meat on the stock tires, so getting a 170/90/15 for the rear will wait 'til next spring, along with trying to improve the stock suspension.
The wife is glad we're also keeping the '95 Magna--she doesn't seem to want to join me on the back of the Max (cue the close up of the lone tear running down my cheek) and her ass is spoiled by the Mustang Regal (so is mine).
My thanks, once again. Beers are on me.

 

[44 magnum]

Re: success!

Hey there Vin, welcome! Glad to hear your '92 is up and running now. Wanted to run something by you regarding your desire for a windshield.

When I first bought mine, it had the little one on there from the PO. Surprisingly enough, removing the screen actually removed some of the turbulance I was fighting once I'd reach speeds over 60 mph. The only purpose that little screen seemed to serve was to keep bugs off the speedo.

What really changed my mind about the Vmax's nakedness was when I swapped the stock bar for a drag bar. It brought my hands foward, just enough to facilitate a bit more of a forward lean, minimizing the effect of the oncoming air stream. Doing that swap was the difference between starting the fight from say, 60-65 mph, up to about 100 mph before I have to make a conscious effort to keep from being peeled off. Another added benefit is that during your WOT runs, it's easier to hold the F on. LOL!!

Just my two cents Brother.

 

[Rayvin53]

windshield or no?

Yeah, I have a National Cycle Street EX shield on my Magna and it makes it so much more rideable, even though it seriously detracts from it visually. Every once in a while I pull it off and as soon as I hit highway speeds I'm reminded of why I keep it on. The Magna's similar to the Max in how much wind you catch...so I can definitely see why being in a more forward/crouched position would help out. I think I might put some wider bars on just to make it a more comfortable ride, though. Is there anyone on the forum that uses a shield that actually blocks the wind AND improves the aerodynamics? I'm less concerned with the looks and more into better rideability.
So, being we both have a '92, are there any particulars to that year that I should be aware of? How stock is yours? I know they made some improvements, I think in '96, with fatter front forks, screw on oil filter, etc.
Thanks for the shield advice and the welcome, 44mag...is that your son in the avatar?
Vin

 

[44 magnum]

Hehehe!!! No, that's not my son... it's from an insurance commercial a while back of that little boy telling a story. Funny as hell. Well, to me anyway. Check it out...

http://www.youtube.com/watch?v=Q5jVNsiM4IU

Okay, let's see... I was thinking the improvements came in '93. Not sure though. Things like brakes/forks/electrical. Others know these bikes much better than I, but I'm all but positive there's nothing major you'll need to be concerned with in regards to putting a screen on.

How stock is mine? Very stock. The only things that aren't stock are just incidentals. Handle bar/tires/cobra pipes/K&N air filter..... Nothing that's going to amount to much.

As far as getting you a more functional screen, I wish I could help but I'll leave that input in the more capable hands of our resident experts.