Lost mid to top end power.

[Vector LTX GT 08]

The filter isn't on the fuel jets, it's on the fuel inlet from the gas tank, under the needle and seat. Remove the tiny Phillips screw and pull the brass needle seat out of the carb and see what you find?

I apologize if this in error.

View attachment 123836

Ok, this really clears things up. Sorry you have to put up with a newbie. haha. I did not know about the brass needle seat. As the carbs are on the snowmobile now, I am not going to do this right now. As I just got 8 inches of fresh powder on top of 8 inches we already had. I will take the carbs off in the winter to clean the filters, if I have 3-4 days to spare. Thanks Northernsledder!!! Got to ride when you have snow!!!!

 

[grizztracks]

I don't remember there being a filter screen in the Vector carb's and I've had several apart. I believe that's a RX1 carb part

 

[grizztracks]

Yep, RX1 carb has those filters under the seat.

 

[Vector LTX GT 08]

And winter has started. Along with snowmobiling. Did a lot of off trail riding today. I am still having issues with my carbs. Some times it runs great other times not so much, rpm wise. I am going to be taking it off in a little bit to have a guy clean it. And find the problem. I will let you guys know how it is after the guy goes over it/ cleans it.

 

[Metallicat]

Good luck! I had poor top end one year and it was a torn slide diaphragm on one carb. I doubt that is your problem, as mine was self induced. When I installed different springs in the slides I ended up pinching a diaphragm.

 

[grizztracks]

Actually, a bad diaphragm was what I was thinking also.

 

[Metallicat]

Actually, a bad diaphragm was what I was thinking also.

Well, maybe that is something he should check too. You can easily diagnose this. Just push the slides up with your finger and release them. If you have a bad diaphragm you will immediately know.

 

[Vector LTX GT 08]

Good luck! I had poor top end one year and it was a torn slide diaphragm on one carb. I doubt that is your problem, as mine was self induced. When I installed different springs in the slides I ended up pinching a diaphragm.

It might be torn. I do know that I am going to take the carb back off in the next day or so. And clean the needle filters on the three. I did find that when I took the carb apart this summer I did not put the slide diaphragm, back together right on 2 out of the three. They opened way to easy. And that was when I had 7,000 rpms. I have since then fixed them, so now all three open sluggish. They are opening the same as my brothers 09. Do u think one of them might have a small tear? Making it look 1,000 rpms? It does not feel like it is getting enough gas to one of the pistons. And I am wondering since it is an 08 if the guy never cleaned the carbs before me, then one of the filters might be plugged. Thus not allowing enough gas in to the carb, making it only going 8,000 vs the 9,000 rpms or so.

 

[Metallicat]

I lost 1000 rpm with one bad slide diaphragm. But if they all open sluggishly and return slowly and evenly then that is likely not your problem. A bad diaphragm will cause the slide to open and close quickly. Sometimes they don't get seated correctly. Gasoline causes the rubber to expand and they can be difficult to reinstall properly. I've had to bake mine in the oven at 275 degrees I believe to shrink them enough to fit again after a full take apart.

 

[Vector LTX GT 08]

I lost 1000 rpm with one bad slide diaphragm. But if they all open sluggishly and return slowly and evenly then that is likely not your problem. A bad diaphragm will cause the slide to open and close quickly. Sometimes they don't get seated correctly. Gasoline causes the rubber to expand and they can be difficult to reinstall properly. I've had to bake mine in the oven at 275 degrees I believe to shrink them enough to fit again after a full take apart.

Yup, mine where not seated properly when I first took the carbs apart. But now they all are sluggish, and the same as my brothers carbs. I could not get them seated by my self, had to have my brother help me. Now I am not an expert at carbs. But know enough to be dangerous. I think I am going to check and clean the needle filters. I have noticed that at idling runs fine. And all the way up to 6,000 rpms, the motor sounds fine. Now when I start going beyond 6,000, it starts acting like it is starving for gas. Like some thing is plugged some where. And with my brothers, it ran mint. It ran smooth and piles of Rpms. I think I am going to just go with some thing is blocked some where. I will be checking the Slide diaphragms, to make sure they are all the same still.

 

[Metallicat]

Yup, mine where not seated properly when I first took the carbs apart. But now they all are sluggish, and the same as my brothers carbs. I could not get them seated by my self, had to have my brother help me. Now I am not an expert at carbs. But know enough to be dangerous. I think I am going to check and clean the needle filters. I have noticed that at idling runs fine. And all the way up to 6,000 rpms, the motor sounds fine. Now when I start going beyond 6,000, it starts acting like it is starving for gas. Like some thing is plugged some where. And with my brothers, it ran mint. It ran smooth and piles of Rpms. I think I am going to just go with some thing is blocked some where. I will be checking the Slide diaphragms, to make sure they are all the same still.

Try swapping carbs with your brother. That will at least tell you if it is indeed a carb problem.

 

[Vector LTX GT 08]

Try swapping carbs with your brother. That will at least tell you if it is indeed a carb problem.

I have all ready been there, put my brothers carbs on, and it ran great. With his carbs on my sled, mine will go over 9,000 rpms. And have a lot of power, runs like new. So it is a problem with my carbs. Mine feels like it is lagging, like a block in the carbs some where. That is why I thought the needle filters.

 

[Metallicat]

I have all ready been there, put my brothers carbs on, and it ran great. With his carbs on my sled, mine will go over 9,000 rpms. And have a lot of power, runs like new. So it is a problem with my carbs. Mine feels like it is lagging some where, like a block. That is why I thought the needle filters.

Sorry, I did not read through all of the posts! I guess just a complete take apart and clean is warranted. It sucks that Yamaha makes the best 4s engines, yet they were the only ones to put carburetors on them!

 

[Vector LTX GT 08]

Sorry, I did not read through all of the posts! I guess just a complete take apart and clean is warranted. It sucks that Yamaha makes the best 4s engines, yet they were the only ones to put carburetors on them!

Yup, I know. Right now I wish I had the EFI motor. Or a apex motor mounted in the newer vector chassis. -20F where I live right now, with the wind just a blowing.

 

[4strokeluvr111]

That what I meant when I said check the "hats". Wasn't sure if the 4strokes had them.
My 2smokes had these.

Thanks for the pic Northernsledder.

Sorry Steiner but that's just taking a bad shortcut IMO.