Hey folks. Long time lurker; this forum has helped me immensely and I thought I would post not only to say THANKS!! but also to share some information that helped me in this year long endeavor.
Some backstory to the bike: It's a bone stock 2004 with 47K kilometers. My friend was the second owner but had no idea what he was getting himself into. He bought it usedin 2010 from a dodgy Yamaha dealer as-is and doesn't know what, if anything, they did to it after they took it in on trade. After realizing the amount of time and money required to keep a VMax on the road he only plated it 5 of the 11 years he owned it, with the last plate being 2018 (using gas from 2016). The bike came into my possession in June of 2021 and while it ran without issue prior, it wouldn't even attempt to start after replacing the very dead battery.
I wish I had recorded more of the process I went through triaging this bike but in all honesty I thought it would be an easier time than it was and didn't realize what I was getting into . I've resurrected a bike or five in my time motorcycling and consider myself an able shadetree but this is by far the most complex machine I've put my sockets on.
As far as I can remember, it went something like this:
- replaced battery and sorted out the rats nest of wires under the seat after my friend "forgot how it went back together". This wasn't that bad and forum pictures helped me out here.
- gas tank/removal. Oh boy. This was probably the most labour intensive part as it requires pulling apart most of the tail end of the bike. Big thanks to the forum here because the service manual says you have to take way more off than necessary.
The tank was less than half full when it went up and sat with almost 5 year old gas in it by the time I got to it. The tank's condition was VERY rusty but an inspection cam confirmed it hadn't deteriorated past surface rust. The gas was disgusting brown sludge and the fuel sending unit was coated in crud and looked like it came off a shipwreck. I've used tank treatments before and have been left unimpressed. Before having it professionally done I tried another forum trick involving a carton of air gun BB's and some extra strength vinegar. Holy &@#% it worked perfectly! It took 3 days of setting and 4 gallons of vinegar but by the end of it the inside was clean and rust free. I dunked the sending unit in a tall shot glass of seafoam assuming it was toast but it also cleaned up and tested perfectly.
I got lucky and the fuel pump hadn't filled full of too much crud. I put 12 volts to it and it pumped seafoam out of the can with no problems. Replaced fuel filter with OEM. Buttoned everything up on the back, found the rear axle had been put together in the wrong order, and filled with fresh gas. Checked spark on all four cylinders and they were good. Now the fun part.
- carburetors/no start issue
Once again, a huge thanks to the various guides and suggestions on this forum. Only one carb of four drained fuel when opening the drain bolts, so after back blasting some carb cleaner in there some really nasty stuff started coming out. My gas catch can was emerald green with lots of brown stuff at the bottom. Time to start cleaning, but first...
- the bag o rocks
Cranking this thing to get fresh gas and cleaner circulating meant the starter clutch was getting a workout and it wasn't sounding good. I pulled off the side cover to inspect and after ordering three different pullers (thank you, Amazon return policy) got the flywheel off. I once again got lucky; all I had to do was tighten up the bolts and apply a dab of threadlocker. I wanted to remedy this before diving further into the carbs as I figured there would be a lot of cranking involved from here on out. I was right.
- carburetor cleaning via shotgun/peashooting method
I did NOT want to pull the carbs off this thing, although if I had it would have been road ready last year. I legitimately lost count of how many times I pulled them apart to blast them with air and carb cleaner but every time I buttoned them back up and got fuel circulating, more green stuff came out the next time I'd take them apart again. I'd crank the starter for a bit, hear the odd cylinder catch, wait 5 minutes and try it again. After the 3rd time shotgunning the carbs, I was able to coax the thing to start but I had to hold the throttle to keep it from dying. I couldn't get it to start again even after another carb clean. By this point it was September and I didn't have the extra time to sink into the garage so I got it ready for winter and started tackling it again last week.
- another carb cleaner method
I shotgunned the carbs again and now could get the thing to usually start with a bit of convincing but the choke didn't do anything and the throttle was hanging and slowly returning to idle speed. An older mechanic I know with Vmax knowledge gave me a piece of advice: because of the design of all the idle passages and stuff on the back of the carb/inside the float bowl, fresh gas won't get up far enough before the float needle shuts off. As a last resort, he's poured carb cleaner in the bowl overflows and let it set to get farther up there. My mistake was a) draining the bowls before spraying the cleaner and b) not paying attention to how much cleaner I was using as I filled all four cylinders full of the stuff which made for a real mess after I pulled all four plugs and cranked it with rags over each hole to catch the spray .
But it worked! After I remembered to plug the fuel pump back in the bike fired up almost immediately and now took throttle without hesitation. I rode it around the block and the Max ran better than I ever would have expected after all the effort it took to even get it running right. I was more surprised by the carb cleaner being so effective through the drain considering it was only running down the cylinder and not accumulating inside the float bowl.
- fluids
Another oil change was in order now that it was running properly (and the first oil change I did was already black just from circulating from all the cranking on the starter I did... the oil that was in it when I got it likely dated back to 2010 so I really didn't mind doing it twice), as well as brakes/clutch, final drive and coolant. The most complicated was the coolant. Again, thanks to the forum for lots of info and a much better explanation on the drain valve than the service manual gave me.
Anyway... thanks guys! I set out to fix this thing up to flip and after riding it... well... I'm still going to sell it but it's a much harder decision than I thought it would be. This motorcycle is absolute insanity on two wheels and the fact that it ever was greenlit for production blows my mind. I never thought I would want one and have always thought they were a little too over the top but now I get it. I understand the appeal lol. But it's just way too much bike for me and I do not like the feeling of the bike being in control of the rider (it's the first of many, many motorcycles I've ridden where I feel like I'm only along for the ride). I have a newfound respect for this pig and now can say I've ridden one of the most iconic motorcycles to ever come out of Japan.
TL;DR: I bought a VMX12 to flip but it needed a crazy amount of work. The forum helped me out immensely and I wanted to share the one weird trick that dealerships HATE that ended up saving me from tearing the carbs apart and might, hopefully, save someone else some time and effort.
Some backstory to the bike: It's a bone stock 2004 with 47K kilometers. My friend was the second owner but had no idea what he was getting himself into. He bought it usedin 2010 from a dodgy Yamaha dealer as-is and doesn't know what, if anything, they did to it after they took it in on trade. After realizing the amount of time and money required to keep a VMax on the road he only plated it 5 of the 11 years he owned it, with the last plate being 2018 (using gas from 2016). The bike came into my possession in June of 2021 and while it ran without issue prior, it wouldn't even attempt to start after replacing the very dead battery.
I wish I had recorded more of the process I went through triaging this bike but in all honesty I thought it would be an easier time than it was and didn't realize what I was getting into . I've resurrected a bike or five in my time motorcycling and consider myself an able shadetree but this is by far the most complex machine I've put my sockets on.
As far as I can remember, it went something like this:
- replaced battery and sorted out the rats nest of wires under the seat after my friend "forgot how it went back together". This wasn't that bad and forum pictures helped me out here.
- gas tank/removal. Oh boy. This was probably the most labour intensive part as it requires pulling apart most of the tail end of the bike. Big thanks to the forum here because the service manual says you have to take way more off than necessary.
The tank was less than half full when it went up and sat with almost 5 year old gas in it by the time I got to it. The tank's condition was VERY rusty but an inspection cam confirmed it hadn't deteriorated past surface rust. The gas was disgusting brown sludge and the fuel sending unit was coated in crud and looked like it came off a shipwreck. I've used tank treatments before and have been left unimpressed. Before having it professionally done I tried another forum trick involving a carton of air gun BB's and some extra strength vinegar. Holy &@#% it worked perfectly! It took 3 days of setting and 4 gallons of vinegar but by the end of it the inside was clean and rust free. I dunked the sending unit in a tall shot glass of seafoam assuming it was toast but it also cleaned up and tested perfectly.
I got lucky and the fuel pump hadn't filled full of too much crud. I put 12 volts to it and it pumped seafoam out of the can with no problems. Replaced fuel filter with OEM. Buttoned everything up on the back, found the rear axle had been put together in the wrong order, and filled with fresh gas. Checked spark on all four cylinders and they were good. Now the fun part.
- carburetors/no start issue
Once again, a huge thanks to the various guides and suggestions on this forum. Only one carb of four drained fuel when opening the drain bolts, so after back blasting some carb cleaner in there some really nasty stuff started coming out. My gas catch can was emerald green with lots of brown stuff at the bottom. Time to start cleaning, but first...
- the bag o rocks
Cranking this thing to get fresh gas and cleaner circulating meant the starter clutch was getting a workout and it wasn't sounding good. I pulled off the side cover to inspect and after ordering three different pullers (thank you, Amazon return policy) got the flywheel off. I once again got lucky; all I had to do was tighten up the bolts and apply a dab of threadlocker. I wanted to remedy this before diving further into the carbs as I figured there would be a lot of cranking involved from here on out. I was right.
- carburetor cleaning via shotgun/peashooting method
I did NOT want to pull the carbs off this thing, although if I had it would have been road ready last year. I legitimately lost count of how many times I pulled them apart to blast them with air and carb cleaner but every time I buttoned them back up and got fuel circulating, more green stuff came out the next time I'd take them apart again. I'd crank the starter for a bit, hear the odd cylinder catch, wait 5 minutes and try it again. After the 3rd time shotgunning the carbs, I was able to coax the thing to start but I had to hold the throttle to keep it from dying. I couldn't get it to start again even after another carb clean. By this point it was September and I didn't have the extra time to sink into the garage so I got it ready for winter and started tackling it again last week.
- another carb cleaner method
I shotgunned the carbs again and now could get the thing to usually start with a bit of convincing but the choke didn't do anything and the throttle was hanging and slowly returning to idle speed. An older mechanic I know with Vmax knowledge gave me a piece of advice: because of the design of all the idle passages and stuff on the back of the carb/inside the float bowl, fresh gas won't get up far enough before the float needle shuts off. As a last resort, he's poured carb cleaner in the bowl overflows and let it set to get farther up there. My mistake was a) draining the bowls before spraying the cleaner and b) not paying attention to how much cleaner I was using as I filled all four cylinders full of the stuff which made for a real mess after I pulled all four plugs and cranked it with rags over each hole to catch the spray .
But it worked! After I remembered to plug the fuel pump back in the bike fired up almost immediately and now took throttle without hesitation. I rode it around the block and the Max ran better than I ever would have expected after all the effort it took to even get it running right. I was more surprised by the carb cleaner being so effective through the drain considering it was only running down the cylinder and not accumulating inside the float bowl.
- fluids
Another oil change was in order now that it was running properly (and the first oil change I did was already black just from circulating from all the cranking on the starter I did... the oil that was in it when I got it likely dated back to 2010 so I really didn't mind doing it twice), as well as brakes/clutch, final drive and coolant. The most complicated was the coolant. Again, thanks to the forum for lots of info and a much better explanation on the drain valve than the service manual gave me.
Anyway... thanks guys! I set out to fix this thing up to flip and after riding it... well... I'm still going to sell it but it's a much harder decision than I thought it would be. This motorcycle is absolute insanity on two wheels and the fact that it ever was greenlit for production blows my mind. I never thought I would want one and have always thought they were a little too over the top but now I get it. I understand the appeal lol. But it's just way too much bike for me and I do not like the feeling of the bike being in control of the rider (it's the first of many, many motorcycles I've ridden where I feel like I'm only along for the ride). I have a newfound respect for this pig and now can say I've ridden one of the most iconic motorcycles to ever come out of Japan.
TL;DR: I bought a VMX12 to flip but it needed a crazy amount of work. The forum helped me out immensely and I wanted to share the one weird trick that dealerships HATE that ended up saving me from tearing the carbs apart and might, hopefully, save someone else some time and effort.