Wifes viper running lean? Need advise!

super1c

super1c

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Back story: My wifes viper never seems to drink enough oil but plugs are nice and tan, wash was good, comp is good. Was using maybe 16oz for 9gal gas 70:1 ration so lean on oil. For this past ride i shortend up the gap from 21mm to 20mm. Now used about 18oz of oil to 9gal of gas. So a little better but still lean on oil of my 50:1 goal. Problem now is wash is bad. Domes are colored all the way to ends (no wash) with a lot more carbon build up and plugs are much darker with carbon build up. I think for her riding style i leaned it out on gas by increasing oil. She sits in that 30 to 50 mph range all day. Will open it up a bit in the straits but im sure not enough. Needles are at 4th with both washers on top and running opticool. I know proper jet wash reading is a series of chops and check. But ive always just judged by the post ride wash when done. Kind of trend it. This is a big change for her engine. Comp still spot on. I want to move the gap in on the oil another mm but now im afraid ill lean her out even more on gas and burn it down. Should i up the pilot jets to 47.5 along with shortening the gap? Move the needle another half? I dont want to decrease oil for fear of taking out crank, the viper cranks need their oil. Im thinking i need more fuel at the low end for her riding style. Any help or thoughts on this one would be great!! Thanks chris
 
I have the same sled with opticool and clip position as you and have been running mine at 19mm(.75in) for 2 years now with no problems, checked compression yesterday and had 140-140-123 and done 160 miles today, got 16 mpg running 40-60 mph on groomed trail. I have the green spring @ 70 and 49.8 grams total per weight in the primary. Sled has 7500 miles and always use Ipone or Shell Advance Synthetic, I think you'll be good at 19mm!
 
The pistons aren't showing any wash? Not even clean areas at the transfer ports? PTO side doesn't have more wash than the other two?

I will be watching your thread closely myself. Checked wash on both my Vipers this weekend. I used a nice little bendable light that you can stick down in the holes and see the entire piston very well....as opposed to yanking off y-pipes like I had done on previous sleds. Anyway....both sleds are set up with needles the same as yours....on the 4th groove and shims on top. The 04 Viper... plugs and wash look fine. Wash at all the ports and a little more on the edges. Could even say it almost looks a little on the rich side. This sled has more miles with the needle at the 4th groove than the one I'm considered with. The 02...I'm watching more close. It's running leaner on the MAG and center pistons....indicated by wash and plugs. The 04 runs this way also...as most vipers probably do... but the wash still looks good on all of them. The two pistons leaner pistons on the 02 do have color across the whole top..... but you can still see small wash areas at the intake side the ports. Very small amount on the center piston....less than I want to see... and a little more on the MAG side. They don't look overly lean but this is in warm temps and I don't see much margin for safety on those two pistons....in plugs or wash. No signs of detonation but my mag side is colored a bit different with a flat smooth sheen to it while the other two have more dark carbon buildup. The wash is only showing about half a pinky fingernail...if that on the MAG and center of the 02....while the PTO and all pistons on the 04 probably show double that area in wash around the ports. Those two cylinders are also showing little wash at about 10 and 2'o clock on the pistons where the others are showing larger amounts wash and also at other ports around the piston.

If you can't see any wash at the ports....I would be worried also.

I'm thinking about going a little more rich for safety also. It's my back up sled... ridden by other friends so I would rather be on the rich side. I was considering starting my own post but I will watch how yours goes. My thoughts so far with mine have been......considered jetting up but I haven't heard of anyone needing to up the jetting on stock Vipers....though I did read a note somewhere....may have been on a Yamaha jetting chart....that said to increase main jet size by one size using ethanol fuels. Still, I don't think its' the mains I'm worried about. I...like you... haven't read the wash correctly as far as running it in a certain range and killing the motor and reading at that point. Mine was mostly mid range riding and temps in the 30's. Without knowing exactly what range it may be lean in...it probably wouldn't make sense to go up on the pilot and main. My guess is it's the mid range. I'm probably going to try one shim below and one above with the needle in the 4th groove instead of the way they are now with both on top. From what I have read on this site with great write ups from Mr. Viper and others, I'm still inclined to go with more needle adjustment on mine before going to jetting. My babble probably didn't help you but I'm looking forward to seeing the direction you take and how it work out. I would try the 47.5's if you were seeing no wash whatsoever. I can't imagine your not seeing anything on all 3 pistons or at least a tiny bit at the ports unless you missed it.
 
Last edited:
livewire_101proof said:
i did notice a while back that even on yamaha parts microphiche has changed to 47.5 pilots are standard.
Click to expand...

I don't see that. I see 45 as standard with the other sizes listed also
 
bokat said:
The pistons aren't showing any wash? Not even clean areas at the transfer ports? PTO side doesn't have more wash than the other two?

I will be watching your thread closely myself. Checked wash on both my Vipers this weekend. I used a nice little bendable light that you can stick down in the holes and see the entire piston very well....as opposed to yanking off y-pipes like I had done on previous sleds. Anyway....both sleds are set up with needles the same as yours....on the 4th groove and shims on top. The 04 Viper... plugs and wash look fine. Wash at all the ports and a little more on the edges. Could even say it almost looks a little on the rich side. This sled has more miles with the needle at the 4th groove than the one I'm considered with. The 02...I'm watching more close. It's running leaner on the MAG and center pistons....indicated by wash and plugs. The 04 runs this way also...as most vipers probably do... but the wash still looks good on all of them. The two pistons leaner pistons on the 02 do have color across the whole top..... but you can still see small wash areas at the intake side the ports. Very small amount on the center piston....less than I want to see... and a little more on the MAG side. They don't look overly lean but this is in warm temps and I don't see much margin for safety on those two pistons....in plugs or wash. No signs of detonation but my mag side is colored a bit different with a flat smooth sheen to it while the other two have more dark carbon buildup. The wash is only showing about half a pinky fingernail...if that on the MAG and center of the 02....while the PTO and all pistons on the 04 probably show double that area in wash around the ports. Those two cylinders are also showing little wash at about 10 and 2'o clock on the pistons where the others are showing larger amounts wash and also at other ports around the piston.

If you can't see any wash at the ports....I would be worried also.

I'm thinking about going a little more rich for safety also. It's my back up sled... ridden by other friends so I would rather be on the rich side. I was considering starting my own post but I will watch how yours goes. My thoughts so far with mine have been......considered jetting up but I haven't heard of anyone needing to up the jetting on stock Vipers....though I did read a note somewhere....may have been on a Yamaha jetting chart....that said to increase main jet size by one size using ethanol fuels. Still, I don't think its' the mains I'm worried about. I...like you... haven't read the wash correctly as far as running it in a certain range and killing the motor and reading at that point. Mine was mostly mid range riding and temps in the 30's. Without knowing exactly what range it may be lean in...it probably wouldn't make sense to go up on the pilot and main. My guess is it's the mid range. I'm probably going to try one shim below and one above with the needle in the 4th groove instead of the way they are now with both on top. From what I have read on this site with great write ups from Mr. Viper and others, I'm still inclined to go with more needle adjustment on mine before going to jetting. My babble probably didn't help you but I'm looking forward to seeing the direction you take and how it work out. I would try the 47.5's if you were seeing no wash whatsoever. I can't imagine your not seeing anything on all 3 pistons or at least a tiny bit at the ports unless you missed it.
Click to expand...

I could be missing the wash as it might not be as defined as my other two vipers. My daughter and i are on the gas way more then the wife. Those two have the easy to read wash marks at the ports and dark in the center to tan on the edges. My wifes just looks dark and carboned up. Plugs much darker also. Was great wash before adjusting to increase oil. With all the midrange problems the vipers have i didnt want to lean it out anymore. Might move needle a half for starters and see what happens. This is just making me a bit nervous.
 
not singling out anyone, dont take it personal

I am not picking on anyone, this is just for general referance:

This is like the 5-6th thread I have seen lately with running lean and wondering why, burned up engines, general problems because your adding more oil to the sled.
(I call these self inflicted problems :o| )

IF YOU ADD MORE OIL TO GAS YOU LEAN OUT THE JETTING BECAUSE THE SLED IS GETTING LESS GASOLINE AND MORE OIL!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

so having said that if your going to run the oilpump richer you need to ADD gasoline to the fuel curve via the jetting.... somewhere.

In your case Chris, youd need to likely move the 1 shim under the clip in 4th groove and 1 on top, this will be 3.5 needle spot. With your wife riding it slow( in the big timing section and biggest heat making area of powercurve) it will be needed for cheap insurance against engine failure in the lean needle section on a viper.
As for the oilpump, I am unsure why everyone wants to run vipers rich and srx's lean, its the SAME 8dn(srx) pump. The stock oilpump gap setting is 20.5mm + or - 1mm so 19.5-21.5 is factory specs. If you were using the cheap yamalube I can see wanting to be on the richer side of the pump setting, because the oil is not as good at protecting stuff as the newer fully synthetic stuff is , coupled with todays low octane crap fuel I would run a 3.5 needle for sure.
If your running a good fully synthetic oil like amsoil or whatever brand "x" you like, the leaner side wont hurt anything, the oil is going to lube the bearings just fine and offer more then adequate protection, its NOT going to keep it from burning down from a lean air to fuel ratio! :rulez:

add oil, you need to add gas in the form of richer jetting or higher octane fuel at the very least. On a viper you need to address the needles regardless, or the engine will address you with a failure in either the mag or center cylinder. You can take that check to the bank!
 
super1c said:
Back story: My wifes viper never seems to drink enough oil but plugs are nice and tan, wash was good, comp is good. Was using maybe 16oz for 9gal gas 70:1 ration so lean on oil. For this past ride i shortend up the gap from 21mm to 20mm. Now used about 18oz of oil to 9gal of gas.
Click to expand...

I think I would go back to your original setup. I've been playing the same game as you except with different jetting due to my altitude. I think the ratio calculation is dependent on how the sled is being driven. For instance if you let it idle for a whole tank (what a waste that would be) you would probably have a calculation to come out to be 100:1 or more. But if you're hard on the throttle you would probably have a much richer oil ratio (notice that I said oil ratio, not rich jetting). The reason being is that the curve is not linear. I think the oil demands are different depending on the heat and loading demands. So it's actually leaner on oil when idling compared to wot. Of course a richer oil ratio leans the fuel ratio. Fuel cools and oil lubricates. So I have to believe that if you're w/in tolerances on your oil cable setting then your lubrication needs are met (Because Yamaha is just that good)! So at that point it's all about the cooling (with fuel) or jetting. And that's where the wash comes in. You are adjusting jetting for wash. I don't think you adjust oil for wash.

I also remember a thumb rule I read here on TY that running around one pint of oil is what you want per tank of fuel. So according to that you"re actually slightly richer on oil then the thumb rule. And that's before you adjusted the oil cable.
 
Newbee said:
I think I would go back to your original setup. I've been playing the same game as you except with different jetting due to my altitude. I think the ratio calculation is dependent on how the sled is being driven. For instance if you let it idle for a whole tank (what a waste that would be) you would probably have a calculation to come out to be 100:1 or more. But if you're hard on the throttle you would probably have a much richer oil ratio (notice that I said oil ratio, not rich jetting). The reason being is that the curve is not linear. I think the oil demands are different depending on the heat and loading demands. So it's actually leaner on oil when idling compared to wot. Of course a richer oil ratio leans the fuel ratio. Fuel cools and oil lubricates. So I have to believe that if you're w/in tolerances on your oil cable setting then your lubrication needs are met (Because Yamaha is just that good)! So at that point it's all about the cooling (with fuel) or jetting. And that's where the wash comes in. You are adjusting jetting for wash. I don't think you adjust oil for wash.

I also remember a thumb rule I read here on TY that running around one pint of oil is what you want per tank of fuel. So according to that you"re actually slightly richer on oil then the thumb rule. And that's before you adjusted the oil cable.
Click to expand...


Excellant post, thats 110% exactly right. "you dont adjust piston wash with oilpump ratio!" ;)! ;)! ;)! ;)!
 
mrviper700 said:
I am not picking on anyone, this is just for general referance:

This is like the 5-6th thread I have seen lately with running lean and wondering why, burned up engines, general problems because your adding more oil to the sled.
(I call these self inflicted problems :o| )

IF YOU ADD MORE OIL TO GAS YOU LEAN OUT THE JETTING BECAUSE THE SLED IS GETTING LESS GASOLINE AND MORE OIL!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

so having said that if your going to run the oilpump richer you need to ADD gasoline to the fuel curve via the jetting.... somewhere.

In your case Chris, youd need to likely move the 1 shim under the clip in 4th groove and 1 on top, this will be 3.5 needle spot. With your wife riding it slow( in the big timing section and biggest heat making area of powercurve) it will be needed for cheap insurance against engine failure in the lean needle section on a viper.
As for the oilpump, I am unsure why everyone wants to run vipers rich and srx's lean, its the SAME 8dn(srx) pump. The stock oilpump gap setting is 20.5mm + or - 1mm so 19.5-21.5 is factory specs. If you were using the cheap yamalube I can see wanting to be on the richer side of the pump setting, because the oil is not as good at protecting stuff as the newer fully synthetic stuff is , coupled with todays low octane crap fuel I would run a 3.5 needle for sure.
If your running a good fully synthetic oil like amsoil or whatever brand "x" you like, the leaner side wont hurt anything, the oil is going to lube the bearings just fine and offer more then adequate protection, its NOT going to keep it from burning down from a lean air to fuel ratio! :rulez:

add oil, you need to add gas in the form of richer jetting or higher octane fuel at the very least. On a viper you need to address the needles regardless, or the engine will address you with a failure in either the mag or center cylinder. You can take that check to the bank!
Click to expand...

Thanks guys, as you stated mrviper self inflicted problems. I am my own worst enemy at times. Will be putting pump back to stock and just hope i didnt cause any damage running lean like that. Compression is spot on from beginning of season and i didnt see any pitting on domes. Ill just have to run it and check them again. For my wife i am going to move the needles one more half step just for safety. Taking both my other vipers back to stock settings also. I wonder if this isnt part of that idle hang problem im having on my viper.... hmmmmmm. This is a lesson learned and i should leave well enough alone. Im in the medical field and we always say pts now know just enough to be dangerous with the info on the internet. Web MD has made a millon people a doctor. I need to heed my own words and leave the mechanic stuff to the pro's and not play around with stuff i only know half of the info. Thanks again guy's, learning somthing every day! Chris
 
Chris, the reason the other 2 sleds look good is like you said "you and the daughter are on the gas more" and out of the mid range cruise speed where all the timing and heat build up is, so thats likely why they look fine. Dont take my post the wrong way, nothing wrong with asking questions, its alot cheaper then rebuilding a engine...lol

3 basic things for a viper to run good and be very reliable:

1.) run the best premium octane gas you can get
2.) raise the needles
3.) run the best quality oil you can afford

those 3 things followed and they are pretty much bullet proof!

Dont be afraid of a viper just be "informed" and youll have a great time riding and no worries.
 
mrviper700 said:
Chris, the reason the other 2 sleds look good is like you said "you and the daughter are on the gas more" and out of the mid range cruise speed where all the timing and heat build up is, so thats likely why they look fine. Dont take my post the wrong way, nothing wrong with asking questions, its alot cheaper then rebuilding a engine...lol

3 basic things for a viper to run good and be very reliable:

1.) run the best premium octane gas you can get
2.) raise the needles
3.) run the best quality oil you can afford

those 3 things followed and they are pretty much bullet proof!

Dont be afraid of a viper just be "informed" and youll have a great time riding and no worries.
Click to expand...

Thanks don,
Didnt take the post the wrong way and i will keep asking when i dont know or not sure. I was just poking a little fun at myself! LOL! Thanks for the great info and clearing a few misconceptions i had. Ive been doing all three things you said. Gotta love all the great guy's and info on the site.! Chris
 
A couple of bucks said:
Next time ya go out, ride the wifes sled w/ the readjusted cable. And have the wife ride yours. Then look in the cylinders and be the judge. Just an idea.
Click to expand...

Thats a good idea, im going to do that. Been wanting to do that anyway. Ive never really rode it for a period of time yet, just testing stuff.
 
mrviper700 said:
Chris, the reason the other 2 sleds look good is like you said "you and the daughter are on the gas more" and out of the mid range cruise speed where all the timing and heat build up is, so thats likely why they look fine. Dont take my post the wrong way, nothing wrong with asking questions, its alot cheaper then rebuilding a engine...lol

3 basic things for a viper to run good and be very reliable:

1.) run the best premium octane gas you can get
2.) raise the needles
3.) run the best quality oil you can afford

those 3 things followed and they are pretty much bullet proof!

Dont be afraid of a viper just be "informed" and youll have a great time riding and no worries.
Click to expand...

What oil do you think runs in the viper the best?? I'm running amsoil interceptor.
 
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