THIS PAST SATURDAY ME AND SOME FRIENDS WERE GOING RIDING. WHEN WE GOT THERE WE UNLOADED AND I WAS GOING TO CRANK MINE AND LET IT WARM UP. BUT AS I WAS TURNING IT OVER IT BACK FIRED AND MADE A HECK OF A NOISE AND WOULD NOT START AND THE ENGINE STARTED SOUNDING LIKE SOMEONE POURED GRAVEL IN IT. AS WE WERE CHECKING EVERY THING LIKE COMPRESSION, SPARK PLUG AND OTHER THINGS THAT MAY KEEP IT FROM STARTING WE NOTICED THE CARBURATORS WERE BLOWN OFF! SO I LOADED IT UP AND TOOK IT BACK TO THE DEALER AND THEY SAID IT MAY HAVE JUMPED TIME? ANYONE HAVE ANY IDEA WHAT MAY HAVE HAPPEND. BY THE WAY THIS IS MY FIFTH TAKE OFF GAS!
THANKS,

 

I think mine did the same thing this weekend. I came off this really big jump...landed....hit the throttle ...then my Raptor started to seem to be choking to death. I would try to give it gas but the thing would miss and occasionally backfire. I checked the choke and the cable but found nothing. I mean this sucker did not have enough power to make it back to the truck. After further review we pretty much determined that the thing jumped time. We also think that I may have somehow sheered the woodruff key. I have the Curtis Sparks key in hand and hope to use it if this is the problem. Let me know what you find out. My dealer is not open on Monday's so I will have to wait until tomorrow to get it to the shop.

 

WELL THE NIGHT BEFORE I WAS OUT RIDING AND MINE DID THAT ALSO. IT WOULD STUMBLE AND BACK FIRE I THOUGHT I WAS RUNNING OUT OF GAS I COULDNT SEE IN THE TANK SO I PUT ON RESERVE AND FLEW HOME. AND THATS THE LAST TIME IT RAN!

 

And I almost bought one, thank god I didn't.

 

I knew going into a first year production bike that "Pioneers gets the arrow's"...but geezzuss...I did not think I was getting into Little Big Horn.

 

This seems like a pretty rare occurance to me, as you two are the only ones I've heard about it from. As far as the first year blues, remember that the Banshee has been virtually identical every year since its first run in '88. Not a bad track record for Yamaha.
By the way, when you leave the caps lock key on all the time, IT SEEMS LIKE YOU ARE YELLING. Just a friendly tip from a fellow Alabama boy. Good luck with your Raptor.

 

Unfortunately, I don't think this is a rare occurence. It happened to me yesterday and the dealer told me that it happened to another guy that bought one.

It was just after starting, I let it warm up. When I got on and gave it throttle, it backfired and blew them off.

My guess is that it is already running on the lean side, and with the cooler weather, it has pushed it over the edge and into a severe lean condition allowing it to backfire. I had the dealer put the carbs back into the boots, and it seems just fine, so I don't think it broke anything. Yamaha needs to address the lean condition though and get it straightened out before it tears something up.

 

There are two possibilites. The Raptor has a sensor on the left brake lever that will make the engine backfire if you're trying to drive it with the parking break on. You can trace that wire to a pigtail and unplug it to TEST if that fixes the backfiring.

Our test Raptor "broke" over the weekend too. I heard how it was fixed second-hand so I'm not entirely sure of my facts yet. But apparently between the cylinder and the carb there was something that came loose and allowed the engine to suck air. Therefore, no gas was getting to the engine. When this happened, the motor was hot and sounded like it had thrown a rod or like it had "sand it" as the original poster here described. This is a normal sound for the big 4-stroke engine. We suspect the noise is coming from the starter. Once we fixed the vacuum leak all was well. We'll be reporting the details in our review of the Raptor but for now I thought I'd share the info on the vacuum leak because it sounds like the problem the original poster described.

Dave Beckstrom
President
ATV Connection, Inc.

 

Thanks Dave.

It sure is strange that they all seem to be having this problem all of a sudden. I'm still betting it has something to do with the cool weather causing it to run "leaner" than usual.

What came loose on you test quad was probably the rubber boot that connects the carbs to the intake. The backfire has so much of a pressure spike, that it blows the carbs loose from the boots.

With the engine practically open at the manifold, you are more apt to hear the engine noises as you described since it is not muffled through the intake system. I've also notices a loud knocking noise at times that I've accidentally killed the engine. I believe that noise is related to the starter as you mentioned. If the loud noise was "rod" related, I suspect a lot of us would have our Raptors back in the shop with a trashed engine.

I think this will all be solved with corrections in the jetting.

 

although I havent had a bad experience yet, I do have a few complaints. The first one being that I dont know if it is specifically my bike or others, but If I want to just push in the clutch and roll it back out of the way in my garage it doesnt move, The clutch never seems to function until warmed up. Also If i dont park in neutral and try and start obviously the clutch doesnt work and it lunges forward upon hitting the ignition. Second thing I have noticed Upon starting is that apparently the Auto compression release gets knocked HARD sometimes when cranking it and it not starting and it sounds like a big metal to metal slap. Not very encouraging.
I also noticed that there is a slip on cap of some kind on the left carb boot, Is this what is coming off? it appears to be for some sort of placement of a sensor or something but is not used so it is just capped off. Its right next to the head and would suck a lot of air if removed or knocked off. Other than that I guess Im going to try and put mine through hell to see if its going to hold up. I have to say it is the best bike I have ridden but if the problems that you guys are having manifest themselves in my bike Im gonna let Yamaha, the magazines, and the CSPC know. They need to fix this crap now. If I were you guys and they didnt Id tell them that according to the Lemon Law they get 3 times and then you get a New one or whatever else you want.