Nytro Mcx question

[DLUX]

just wondering if anyone else is having trouble with a low speed stumble or hesitation on there mcx turbo nytro? some people are saying its a nytro factory setting but i have ridden several other nytro's and none of them do it. it also seems like its getting worse the more i ride it... i have tried adjusting the co's but it will not even run if its not set at zero.

Thanks

 

[maniac mechanic]

Try installing new spark plugs. had afew Apex's start to run funny and turned out to be a couple bad plugs. somtimes it's the simple things that cause the most grief.


jeff

 

[snowy1]

its a common problem they are still working on it, seems to be mostly at higher elevation, I am going to try a couple things, I will let you know if I figure anything out.

 

[air-x]

I just picked up a mcx nytro and I have a stumble also. I talked to PG yamaha and they were no help

 

[modsledr]

Having the same prob with the S/C Nytro...was told that it is a conflict with the anti-compression braking fuel management system. Not sure if this is true, just what I was told.

modsledr

 

[snowy1]

I pulled the head shim out and stacked 3 head gaskets, the head shim is .075 plus stock gasket = .095, stock is .020 and with 3 stacked I am at .060 now. I still have a small stumble but it is not nearly as bad as it was with the head shim. I have one more thing to try I will let you know how it works out.

 

[EZmoney]

I read some guys are running the attitude box with the mcx kit some where on here. Do those sleds have the burble down low as well or is the same any one know?

 

[0007]

Is this particular stumble happening during repeated blip's of the throttle?

 

[Thistledoo]

Mines done it too since I put the MCX kit on. HAve tried the CO's all over the place and it doesnt change a thing. Its right off throttle....like bop bop then it cleans up and rips. Keep this thread alive cause its one thing I'd like to get figured out for sure...Along with that noisy a$$ clutch

 

[Washy]

Mine does the same thing. Gets worse the higher I go. I have tried from -20 to +10 on the CO settings. -20 and it was too lean a 5500 rpm. 16 on A/f ratio.

 

[0007]

Ya know
I been thinkin (that dont happen too often)
It sounds like it's worse with guys who have done the CR tunnel dump
And/or moving the filter out behind the seat, adding length to the intake
I have MC muffler and it annoyed me for about an hour but im OK now
I would call it minor, I do notice that blipping the throttle 2 or 3 times makes it rich and gurgly, Apex is the same, dont blip

 

[SLY]

I have a bigger air filter but no tunnel dump. Seems to run fine. After the way the Phazer ran with a tunnel dump, I didn't like the idea. If it can't blow it can't suck = rich. My CO is at -20

 

[snowy1]

I put a 3" elbow on my exhaust cut a hole in the side of the tunnel and let it blow out the side so there is know resistance. I did notice when I had it dumping in the tunnel it would bog alittle in the deep powder.

 

[1madbird]

I have a side mount on my nytro and the exhaust dumps right out the side panel and Im using the Additude box and it still hesitates Im told that it is becuase of to low of fuel pressure and that you need to put a bigger pump and regulator on it.

 

[snowy1]

I put a seperate pump and regulator on mine, feeding the mcx injectors and the stock fuel system feeding the stock injectors, so they are two seperate systems plenty of fuel now, I only got to make a short run up the road today it seemed to still have alittle stumble but I will try to take it out tomarrow and due alittle better test.

 

[SNOW JW]

Snowy give Mark a call his new update does work. I also sent you a PM