Phazer Clutching and hitting rev limiter?

[MOUNTAIN VMAX4]

I have a friend who has a Phazer MTN as do I. Him and I are debating what caused his bottom end to come apart it basically threw a rod. It is not a turbo, has an exhaust, airbox mod, and he enrichened the fuel curve 1 setting. He thinks that before it went he hit the rev limiter too much and thats what caused it. He has about 8000 miles on his sled. Now he is clutching to never hit the rev limiter so when he is climbing he will only be hitting about 10500-10800. I like to hit 11300-11600 when climbing, so I hit the rev limiter occasionally on the flats or if I lose traction.

Do you think the problem is reving to high on occasion or is the rev limiter supposed to limit the revs enough even if you are bouncing off the limiter to keep your motor from failing?

Or do you think there was some flaw in his motor upon assembly at the factory?

 

[greenthumb]

Have you checked out the bearings?

 

[UP bushman]

IMO at the rev limiter 12,400 rpms the motor is turning at an amazing number of revolutions of force. I was talking to the wrench at my dealer and he was saying that if Yamaha stayed with the solid one piece roller bearings in the piston rod it would not be near the issue that presents it's self now. Rod bearing failures in the older Yamaha Phazer or other model motors was next to nothing. The rod bearings in the new Phazer motor has a split rod bearing like a V8 and at that rpm issues will arise.

In closing when the mechanic said that I went right to work on dropping the rpms to prevent the disaster of a 4 stroke from happening. With some testing on the primary weights due to rider weight and riding conditions. I have found better performance with the setup and no fear of the rev limiter. The only time it might hit the rev limiter is if I launch and am on the throttle.

 

[blueironranger]

popped my motor at 790 miles, Yamaha put a new one in............ It reved WAY too high out of the box, over 3/4 throttle was on the limiter. Even with sea level clutch specs it turned 11,800 after the 300 miles of break in. Dealer said it was fine but I think that led to the rod snapping, The ROD was the cause of the failure in my case, no seized bearing. I've had it clutched properly the whole time with the new motor though. I have her weighted down to turn 11,200 WOT on hard pack which gives me ~10,400 in the DEEP stuff. Don't worry about lower RPM's in the deep, this isn't a 2 stroke, these little guys make peak torque at 8,800 rpm, as long as your above that it isn't going to bog out on you. Has your buddy ever dumped it on it left side or upside down, had oil come out, and the motor was still running. Seems to be a common issue on the phazers. The engine gets oil starved, slightly damages the bearing surface, then a few 100 miles later it tosses a rod.

 

[Ruckus]

Has your buddy ever dumped it on it left side or upside down, had oil come out, and the motor was still running. Seems to be a common issue on the phazers. The engine gets oil starved, slightly damages the bearing surface, then a few 100 miles later it tosses a rod.

Exactly what happened to mine.

 

[MOUNTAIN VMAX4]

OIL STARVATION

I think we all have done that a couple times on our Phazers. Usually they kill them selves pretty quick. But I could see that being more of a problem then occasionally hitting the rev limiter. I guess I could see a problem with hitting the rev limiter all the time. I will probably clutch it just a hair lower and make sure it shuts off quicker after a rollover.