Etec 800 won't pull 7900

[Brapster]

Hey all. Scratching my head with this one. Replaced motor few yrs ago and Did vforce reeds as well. Rode fine until last couple seasons not pulling 7900 up at elevation. Had clutches rebuilt, new roller and new belt so ruled that out but it will only pull 76-7700 and adjusting the clickers doesn't bring it up as it did in the past. It also seems like while on the trail up it would pull rpm but once up top just doesn't pull peak rpm and has the odd bog here and there. Anyone have any other ideas? Hoping to try it around home next little bit here as well as we just got some snow. Thanks

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[greenthumb]

Maybe sticky rave valves.

 

[MK4TDI]

Hey all. Scratching my head with this one. Replaced motor few yrs ago and Did vforce reeds as well. Rode fine until last couple seasons not pulling 7900 up at elevation. Had clutches rebuilt, new roller and new belt so ruled that out but it will only pull 76-7700 and adjusting the clickers doesn't bring it up as it did in the past. It also seems like while on the trail up it would pull rpm but once up top just doesn't pull peak rpm and has the odd bog here and there. Anyone have any other ideas? Hoping to try it around home next little bit here as well as we just got some snow. Thanks

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Check the rave valves, bellows too, usually they throw a code though if they aren't in the correct position. When was the last time the fuel filter was changed ?

 

[The Kickass One]

So many things, fuel pump, broken spring, try another belt, spark plugs, stator, rave valves, shitty fuel etc

 

[MP Kid]

Need a little more info…
Mileage?
800 etech - what year?

When you say that the clutches were “rebuilt”, what does that mean…?
I’d lean towards a weak primary spring.
Have also seen relatively new spark plugs do the same thing.

 

[greenthumb]

When was the last time the fuel filter was changed ?

YES! Forgot all about that. Happened to me. Can cause a behaviour just as you are experiencing.
You don’t need to spend $30 from the dealer either. Here are part numbers.
Napa 3095
Fram G3606
Wix 33095
There’s room on the xm for a larger filter, but I don’t have that part number offhand.
Also, some xm’s suffered from a loose fuel pressure regulator that could cause similar symptoms. Free fix, but you need to pull the pump assembly out of the tank.

 

[The Kickass One]

Plus fuel filters in pump in tank could be plugged. Sounds a fuel issue, especially if loss of power or backfiring… which then could lead to other issues

 

[Brapster]

Need a little more info…
Mileage?
800 etech - what year?

When you say that the clutches were “rebuilt”, what does that mean…?
I’d lean towards a weak primary spring.
Have also seen relatively new spark plugs do the same thing.

2015 with 11k kms new motor with only around 2k on it. Fuel filter was changed id say around 7k kms i believe. And clutches are rebuilt with new springs

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[MK4TDI]

2015 with 11k kms new motor with only around 2k on it. Fuel filter was changed id say around 7k kms i believe. And clutches are rebuilt with new springs

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The 15's had a service bulletin for the fuel pressure regulator, it would sometimes wiggle out of its spot, I would definitely try the filter first, as greenthumb said don't buy at the dealer.

I have had new springs not work correctly, but not too often. That goofy check valve system between the reed valves might have a crack in it which would cause the raves to not work 100% correct, but just enough not to throw a code.

 

[Stevemtb]

I had the fuel regulator issue on mine and one of the symptoms was not starting first pull. Sometimes it took many pulls to start. If you ever have starting issues I’d pull the pump out and take a look, although it is a bit of a pain. Make sure fuel level is low lol

 

[Brapster]

I had the fuel regulator issue on mine and one of the symptoms was not starting first pull. Sometimes it took many pulls to start. If you ever have starting issues I’d pull the pump out and take a look, although it is a bit of a pain. Make sure fuel level is low lol

Has no issues starting runs like a charm until up in elevation

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[Stevemtb]

Has no issues starting runs like a charm until up in elevation

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Probably not the regulator then imo. Mine ran ok but it was obvious something was wrong even when not under full load.

 

[Bnorth]

I would start with the primary clutch. How many km since rebuilt? Check spring cup bushing and sliding sheave bushing to start. Also make sure arms move freely and aren't gummed up as well as rollers move smoothly and no grooves in ramps.

 

[Brapster]

I would start with the primary clutch. How many km since rebuilt? Check spring cup bushing and sliding sheave bushing to start. Also make sure arms move freely and aren't gummed up as well as rollers move smoothly and no grooves in ramps.

I think 3 trips since the clutch has been rebuilt so tops 400-500kms and all that has been done and after the full rebuild no change as it was doing it before rebuild as well

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[catrutt]

My 2015 needed the secondary spring replaced after about 3400 kms. would only pull 7500 rpm at elevation. I forget what spring Baker sold me but it was perfect after replacing. Same belt same everything just secondary spring that was different from stock.

 

[lilduke]

Sounds like it needs a 50 shot of nitrous

 

[The Kickass One]

With your new information regarding clutching changes… I may have read your first post wrong. I’m leaning totally towards fuel pump, unless it has been replaced as well as all the fuel filters.

 

[Brapster]

Changed fuel filter and going to clean rave valves and go from there thanks guys

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[catmando]

Well I have a Xm turbo for sale, or lots of parts if ya figure it out.

 

[1100]

If you pull the plastic cap off the raves. You can zip tie them up to the frame ahead of them for testing purposes, bottom end will be dead but it will open up on top end . If it changes something I would dive into them. If it doesn’t I would put a fuel pressure gauge on and see if it drops off as your driving.