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Help. Help. Cylinder #3 not firing.

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pikipikos

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Hi guys. Everything is shitty these days with my Max. I just find out that Cyl#3 is not firing.. Nothing. I had a new OEM COIL. Replaced it. Nothing. I switched between cyl 2 and 3 the coil plugs and is firing.
I followed the service manual troubleshooting. And then i discover that i cannot find the 5 pin plug if the pickup coil to measure the ohms.
I am suspecting that the previous owner, who had a Vboost controller fucked it up.
Help me how to start and where to end

Pikipikos (desperate)
 

Fire-medic

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Check out this thread: Pick up coils
I don't know how one cylinder would drop from a bad pick-up coil. If it's the early ignition ('85-'89) then it uses two pick-up coils, and if one went bad, it would run on two cylinders.

The '90-'07 bikes use a single pick-up coil, if that goes-out/stops working, you lose all-power, no cylinders work.
 

Fire-medic

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Hello Firemedic. Mine is a 1994 model, Canada specs. In the service manual, speaks about checking the pickup measuring resistance from a 5pin fuse.
I cannot see such a fuse. With 5 wires on it.
Is the manual wrong?
Ok what i do next?
You are looking at the repair section for the early pick-up (1985-1989) & yours is a 2 wire pickup, 1990-2007. It's not the pick-up. Three cylinders work. One doesn't. That cannot happen with your engine/pick-up, where the cause is the pick-up. Yours, all cylinders work or (if the pick-up coil is bad) none work.

The 5-pin pick-up coil 'fuse' you are probably looking-at is I suspect, a connector, male/female. And as I said, you do NOT have that style pick-up coil, yours is a 2-wire connector.

Does it not fire on #3 at idle, but if you rev it to say, 5,000 RPM, it begins to fire on that cylinder? If that is the case, I suspect a plugged pilot jet, which controls fuel flow at idle and just-above.
 
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MaxMidnight

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As Mr Medic suggests, if it cuts in as the revs are increased then I would look for a fuel issue and a plugged pilot jet is a good starting place.
If it doesn't then you are either looking at a compression issue or electrical.
I also agree that the pick-up coil is not the problem.
The coil will fire when the ignition control unit (ICU) puts that coil to earth.
First step would be to check that you have 12 volts going into it (red/ white wire) and continuity back to the ICU.
If that checks out OK and as you have replaced the coil and swapped plug lead and plug cap (?) then I would suspect an issue with the ICU.

It may also be worthwhile doing a compression check just to rule that out.
 

pikipikos

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As Mr Medic suggests, if it cuts in as the revs are increased then I would look for a fuel issue and a plugged pilot jet is a good starting place.
If it doesn't then you are either looking at a compression issue or electrical.
I also agree that the pick-up coil is not the problem.
The coil will fire when the ignition control unit (ICU) puts that coil to earth.
First step would be to check that you have 12 volts going into it (red/ white wire) and continuity back to the ICU.
If that checks out OK and as you have replaced the coil and swapped plug lead and plug cap (?) then I would suspect an issue with the ICU.

It may also be worthwhile doing a compression check just to rule that out.
Just for your knowledge, not that this is your issue. View attachment 72299View attachment 72300
Hi guys,
I spent 2 days on the wiring. Came out to be the red/white wire on the coil, no continuity! I replaced it, cleaned and rubbed everything up. Measured the pressure sensor, pick-up coil 119ohhms,and all the contacts on the TCI. OK. IT FIRES AT LAST.
I took it for ride today morning, stumbles a bit on the highway above 100mph.WHY? CARBS ARE CLEANED.
one thing i noticed when cleaning the carbs is that PAJ2 is #150 instead of #170. 😩 I dont know why. Does this affect the highway stumble? Should i make another balance check on carbs, maybe i moved something during wiring checks?
 

Traumahawk

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Hi guys,
I spent 2 days on the wiring. Came out to be the red/white wire on the coil, no continuity! I replaced it, cleaned and rubbed everything up. Measured the pressure sensor, pick-up coil 119ohhms,and all the contacts on the TCI. OK. IT FIRES AT LAST.
I took it for ride today morning, stumbles a bit on the highway above 100mph.WHY? CARBS ARE CLEANED.
one thing i noticed when cleaning the carbs is that PAJ2 is #150 instead of #170. 😩 I dont know why. Does this affect the highway stumble? Should i make another balance check on carbs, maybe i moved something during wiring checks?
Yes that will cause a stumble. PAJ#2 Controls air from just off idle all the way to redline. So, a decrease in air, will make everything too rich.
 

Fire-medic

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Congratulations on your trouble-shooting perspicacity (persistence and devotion to attention).

One thing which I've heard can affect things is the float bowls' hoses which run from the L-shaped steel tubing on-top of the carb float bowls, to the front left and right sides of the airbox cover. At the airbox cover end, they have brackets they plug-into, where the open end of the hose/bracket has a sheet-steel baffle in-front of it. The float bowl 'breathes,' but the baffle keeps high MPH wind from putting too-much pressure into the float bowl.

I don't recall that the instructions for Stage 7 Dynojet kits mention anything about those steel tubes off the tops of the float bowls needing the hoses when running 4 pod air filters. However, the factory with their airbox saw fit to include them, and they serve a purpose, or else the factory would save $ by not having them.

What size are your main jets? Do you have a jet kit? Do you have the OEM airbox? Is it an OEM filter inside or a K&N pleated cloth filter covered in stainless steel mesh? You could probably get that bike a bit better running by going down from what I suspect youhave for a main jet of 152.5 to a 150 or a 147.5, and going up on the PAJ2 size to what it is in the USA, as trauahawk suggested.

OK, this chart says you should have a 150 main jet if you have a European model, not sure if your Canadian specs are the same as USA or they are European. Then-again, you could be dealing with whatever previous owners did.

VMax carburetor USA and CALIF..png
 
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pikipikos

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Congratulations on your trouble-shooting perspicacity (persistence and devotion to attention).

One thing which I've heard can affect things is the float bowls' hoses which run from the L-shaped steel tubing on-top of the carb float bowls, to the front left and right sides of the airbox cover. At the airbox cover end, they have brackets they plug-into, where the open end of the hose/bracket has a sheet-steel baffle in-front of it. The float bowl 'breathes,' but the baffle keeps high MPH wind from putting too-much pressure into the float bowl.

I don't recall that the instructions for Stage 7 Dynojet kits mention anything about those steel tubes off the tops of the float bowls needing the hoses when running 4 pod air filters. However, the factory with their airbox saw fit to include them, and they serve a purpose, or else the factory would save $ by not having them.

What size are your main jets? Do you have a jet kit? Do you have the OEM airbox? Is it an OEM filter inside or a K&N pleated cloth filter covered in stainless steel mesh? You could probably get that bike a bit better running by going down from what I suspect youhave for a main jet of 152.5 to a 150 or a 147.5, and going up on the PAJ2 size to what it is in the USA, as trauahawk suggested.

OK, this chart says you should have a 150 main jet if you have a European model, not sure if your Canadian specs are the same as USA or they are European. Then-again, you could be dealing with whatever previous owners did.

View attachment 72384
Hi 🔥 Medic! Thanks for the good words.
Canada's specs is full power 145hp model. I dont recall the main jet size. I will change the PAJ2's and take it from there!
By the way, the f.....vboost controller, doesnt work when cold. I have to squeeze it a bit.. Any treatment?
Is hard to get a new one or a good used one..
 

Fire-medic

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Sounds like re-soldering the wires from the plug to the PC board may assist in maintaining contact.

Order some 147.5 main jets when you order the PAJ2's, I think your bike will appreciate being leaned-out a bit.
 

pikipikos

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Sounds like re-soldering the wires from the plug to the PC board may assist in maintaining contact.

Order some 147.5 main jets when you order the PAJ2's, I think your bike will appreciate being leaned-out a bit.
I did resolder the wires. It looks that that was the problem.. 1000 thanks!
One more thing guys: i have a friend who owns a 2000 model, crashed. Needs frame anong others. There is an 89 model that is foe sale, parts.
The frame can be used for his bike?
Can i get the electronics, e. g TCI, pressure unit and carbs? Do they comply with my 94?

Again thanks for the help!
 

Fire-medic

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Yes to the frame. The CDI and wire harness is different on a '89 compared to a '94 or a '00. You can use the parts on your bike, assuming that you swap the wire harness, CDI, pick-up coil, and electrical rotor onto your engine. There may be some other minor mods you would need to do for the wire harness, but that's the 'big-stuff.'

1985-1989 uses a two coil pick-up coil design (5 wires). 1990-2007 uses a single pick-up coil design (2-wires). Pretty-sure that you don't need to change the stator, just the rotor.

Yes to the carbs swapping. Better clean them, since they're probably sitting for months since the crash. That means removing them, and splitting the set into two pairs, removing the jet blocks and jets inside them, and a good soak and compressed air through all passages. Make sure that upon removal from your soak, that you lubricate the enrichener pistons immediately, as they will rust/corrode-solid quickly. I normally leave-alone the enricheners, if they are freely-moving before the soak, though of-course, I would open them up if they were frozen.

The pilot jets in the jet block have tiny holes, you need to ensure they are clear before placing them into the carb soak. Here's a shot of the single-strand wire I use to clean the pilot jets. I use it in a pin vise.

The front end, including brakes (2 opposed pistons), triple trees, downtubes (40 mm), and sliders is the same 1985-1992. The 1993-2007 front end is a different spec, including brakes (4 pistons per caliper, total), triple trees, downtubes (43 mm) and sliders. The later model front end can swap onto an early-model frame. The caliper bolt hole spacing is different, so early model calipers will-not fit as a direct bolt-on, to a late-model front-end, and vice-versa.

VMax early pick-up coil 1985-89.jpgVMax late pick-up coil 1990-up.jpgVMax pilot jet.jpg
 
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pikipikos

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Yes to the frame. The CDI and wire harness is different on a '89 compared to a '94 or a '00. You can use the parts on your bike, assuming that you swap the wire harness, CDI, pick-up coil, and electrical rotor onto your engine. There may be some other minor mods you would need to do for the wire harness, but that's the 'big-stuff.'

1985-1989 uses a two coil pick-up coil design (5 wires). 1990-2007 uses a single pick-up coil design (2-wires). Pretty-sure that you don't need to change the stator, just the rotor.

Yes to the carbs swapping. Better clean them, since they're probably sitting for months since the crash. That means removing them, and splitting the set into two pairs, removing the jet blocks and jets inside them, and a good soak and compressed air through all passages. Make sure that upon removal from your soak, that you lubricate the enrichener pistons immediately, as they will rust/corrode-solid quickly. I normally leave-alone the enricheners, if they are freely-moving before the soak, though of-course, I would open them up if they were frozen.

The pilot jets in the jet block have tiny holes, you need to ensure they are clear before placing them into the carb soak. Here's a shot of the single-strand wire I use to clean the pilot jets. I use it in a pin vise.

The front end, including brakes (2 opposed pistons), triple trees, downtubes (40 mm), and sliders is the same 1985-1992. The 1993-2007 front end is a different spec, including brakes (4 pistons per caliper, total), triple trees, downtubes (43 mm) and sliders. The later model front end can swap onto an early-model frame. The caliper bolt hole spacing is different, so early model calipers will-not fit as a direct bolt-on, to a late-model front-end, and vice-versa.

View attachment 72413View attachment 72414View attachment 72415
Thanks for all that comprehensive info friend! 🤓.. Cheers!
 

Fire-medic

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AFAIK, no radial tires rated at the 149 mph speed that Yamaha says our bike can do. I believe there are smaller-engined bikes which share our tire sizes, rated for slower speeds. One thing you want to-do, is to ensure that you buy two of the same type of tire. Using for instance a mix of a radial tire and a bias-ply tire can cause a seriously-unstable motorcycle. Same goes for different types of radial tires. The method of construction being different, can cause a seriously-unstable motorcycle. The way the radial belts are wrapped is what I am referring-to. Some are wrapped perpendicular to the circumference, some are wrapped at oblique angles to the circumference. That affects handling, NOT in a good way if you mix them.

Another problem is in rubber compounds. A hard rubber compound on the rear of our bikes can cause you to lose traction just-from grabbing a sudden handful of throttle, which can break the tire loose. A 'sticky' front tire and a hard, 'high-mileage' rear tire can get you into trouble, the front end sticks, but the rear end wants to-slide, especially with sudden throttle motion: going into a turn carrying a lot of speed, and then grabbing more-throttle. The front sticks, but the rear-end slides. That is not a good combination for safety while riding. Just turning our bikes and grabbing some throttle is enough to break the rear end loose, like turning right at a traffic control device (stop sign or traffic light).

I'd sat that the best bang for the buck I've seen, and what I've bought a pair-of, most recently, were Shinko tires. I do not know of any Shinkos in radials, rated for our bike's top speed, and sized for our OEM wheels.

If you want radials, the best thing to do is to buy an aftermarket larger, wider rear wheel, allowing you to run 17" or 18" tires. A typical wheel width not requiring a cut-up, modified swingarm to fit the different wheel/tire, is a 5-1/2" width. I have a machinist who makes me both 17" and 18" X 5-1/2" wheels. The 17" is much-less-expensive. Both are bolt-ons, as they use the shaft drive hub of the VMax mated to another rim of either 17" or 18" size. PM me if interested. He can make a widened front wheel also.

Typical rear wheel tire sizes for 17" or 18" modified OEM wheels are 160, 170, or 180 widths. Anything more-than that, you will probably need to alter the swingarm to fit the wider tire/wheel. The method of how the wheel was changed to a 17" or an 18" can come into play here, along with the width of the tire selected and mounted. It can be a 'fit and try' scheme.

You can use a radial tire on the front 18" OEM wheel, though the width is NOT optimal. Radial tires use a wider width, the front end of our bikes should have a 3-1/2" wide wheel to allow the best use of the radial tires. I currently use a 110/80-'Z'-rated speed, 18" front tire. I have a 17" wheel in the back. Both tires are radials.
 
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