Two weeks ago my viper was running hard (nearly 110mph on dM), but Saturday the top speed would not go over 88mph. I didn't change anything. I just don't understand why.
Facts:
1. Carbs were cleaned at beginning of the year and run nothing but 92.
2. PowerValves were cleaned less than 200 miles ago. Did not adjust. Sled has 1500 miles. I did not disconnect PV from cable, but cleaned them well.
3. Tach at WOT stayed at 8500 rpm (while going 88 mph on the DM)
4. Belt has about 1500 miles on it. Original.
5. Same plugs for about 1500 miles. Original (Plugs appear rich) oil cable is adjusted according to tech section.
6. Stock clutching and have never cleaned them.
7. Stock gearing.
8. Stock drivers with a 1.352 Cobra.
9. Lights and gauge pod seemed to be acting normal.
10. Snow was fairly hardpacked with scuff of fresh snow (1/2" on top)
11. Viper was sitting in a heated garage since my last trip.
12. Temp was approx. 15 degree F. Carb heaters were OFF
I don't think the Cobra track is really slowing me down as it ripped hard two weeks ago with the track. Do you guys think that an over tensioned track and a belt with 1500 miles could drop my top speed down by 20mph on the dream meter although it ran hard immediately after the track install? I believe my TORS was acting up intermittently as I had to idle down a couple times then it was fine, but that shouldn't slow me down any. Leaving for a trip on Thursday AM, do I have a problem and where do I start. I am nervous. Something doesn't seem right to me.
Facts:
1. Carbs were cleaned at beginning of the year and run nothing but 92.
2. PowerValves were cleaned less than 200 miles ago. Did not adjust. Sled has 1500 miles. I did not disconnect PV from cable, but cleaned them well.
3. Tach at WOT stayed at 8500 rpm (while going 88 mph on the DM)
4. Belt has about 1500 miles on it. Original.
5. Same plugs for about 1500 miles. Original (Plugs appear rich) oil cable is adjusted according to tech section.
6. Stock clutching and have never cleaned them.
7. Stock gearing.
8. Stock drivers with a 1.352 Cobra.
9. Lights and gauge pod seemed to be acting normal.
10. Snow was fairly hardpacked with scuff of fresh snow (1/2" on top)
11. Viper was sitting in a heated garage since my last trip.
12. Temp was approx. 15 degree F. Carb heaters were OFF
I don't think the Cobra track is really slowing me down as it ripped hard two weeks ago with the track. Do you guys think that an over tensioned track and a belt with 1500 miles could drop my top speed down by 20mph on the dream meter although it ran hard immediately after the track install? I believe my TORS was acting up intermittently as I had to idle down a couple times then it was fine, but that shouldn't slow me down any. Leaving for a trip on Thursday AM, do I have a problem and where do I start. I am nervous. Something doesn't seem right to me.
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Check powervalves for a pull through and do a compression check to start with.
You can disable TORS if it concerns you.
As for speed vs speed, just about anything can through you off. Slightly warmer day, more snow of the ground, less packed base, more gas in the tank, you didn't poop that morning, etc.
Was the tank full when you stored it. Perhaps the transition from warm garage to cold on 1/2 empty tank caused some condensation.
110 on DM equals 100 actual, which is about 5 mhp off the top speed of an ALL STOCK Viper on bare ice. Given you are running a bigger heavier track on less then bare ice, that is very good. 88 is low, but like I said it could be anything.
Good example. I ran 114.3 with a stock clutched Viper (empty tank) 2 years ago. Last year I added pipes (+30hp), but ran the exact 114.3. Deeper lug track, warmer day, more gas in tank, track was getting chewed up.
PS - at 15F, keep the carb heaters off.
As for speed vs speed, just about anything can through you off. Slightly warmer day, more snow of the ground, less packed base, more gas in the tank, you didn't poop that morning, etc.
Was the tank full when you stored it. Perhaps the transition from warm garage to cold on 1/2 empty tank caused some condensation.
110 on DM equals 100 actual, which is about 5 mhp off the top speed of an ALL STOCK Viper on bare ice. Given you are running a bigger heavier track on less then bare ice, that is very good. 88 is low, but like I said it could be anything.
Good example. I ran 114.3 with a stock clutched Viper (empty tank) 2 years ago. Last year I added pipes (+30hp), but ran the exact 114.3. Deeper lug track, warmer day, more gas in tank, track was getting chewed up.
PS - at 15F, keep the carb heaters off.
crewchief47 said:
Compression was 105, 120, 120. Currently in garage pulling PV to check pull through and taking off Y pipe to see what the rings look like. I may go borrow another tester to compare the readings. Computer is on in the garage if anyone has any input tonight. I'd appreciate the help. Plugs were dark, wonder if my tester reads low.
How many pulls does it take to get the psi reading. These numbers were after about 10 hard pulls on the rope. No plugs in other cylinders.
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wyseguy
New member
Not to confuse the situation or jack the thread, but....
I have an 02 Viper with ~8400 miles on it. My compression numbers are 118,115,105. Plugs are perfect brown. I installed a brand new 1.375 Cobra about 800 miles ago. The fastest that I can get the sled is 81.5 on the GPS. The sled does hang with my buddy's 04 Viper S to 80 is, and then he pulls away.
Is it possible that the secondary is not shifting into top gear, so to say?
Is it truely possible that the cobra slowed me down that much?
I have an 02 Viper with ~8400 miles on it. My compression numbers are 118,115,105. Plugs are perfect brown. I installed a brand new 1.375 Cobra about 800 miles ago. The fastest that I can get the sled is 81.5 on the GPS. The sled does hang with my buddy's 04 Viper S to 80 is, and then he pulls away.
Is it possible that the secondary is not shifting into top gear, so to say?
Is it truely possible that the cobra slowed me down that much?
wyseguy
New member
jholden said:
I had all plugs removed as well. I pulled 3-5 times to get my numbers. Every gauge is a bit different. I have been using it for years, though, and it seems very accurate.
YAMAHIZAL700
New member
It could read low but when testing instead of higher numbers you want a consistent numbers like 120 120 120 and so forth. Good luck and barrow a nother tester or buy and return one if you have to that way youll have a better idea. Good luck and before you tear into it take some break c leaner and spray around the seals of the case so you can see if your idle goes up. I f it does you need to split case and replace seals before you even think about rings or piston.
Stop the bus, his compression is fine and that test doesn't really tell you much anyway. When you are done playing the the PV go and do some more testing. Try doing a few good pull (2 or 3 from dead stop to WOT) and see if one of your clutches get really hot. Try a new Yamaha belt. Dump the gas and fill with fresh... just don't assume the motor is the cause.
Yes, the numbers appear good. Yamerdown has the right order from here.
Thanks guys. PV's are good. Pretty much still clean and intact from last time. I cleaned them up again and reinstalled. I also warmed the sled back up for about 10 min and tested compression at WOT with another gage. The readings were 110, 125, 125. The original gage gave me 105, 120, 120 again. I know they are a bit low and not to really rely on the gage readings, but it's seem nerve racking when the low readings are on your sled. Pulled the Y pipe and piston/rings appeared OK, but hard to see as I was doing a lot of looking with a mirror. Didn't see anything incredibly bad anyway. I am putting everything back together and I am going to go through the PV adjustment below 900 rpm just to make sure.
I also was wondering about the belt and clutches. I might have to look into that tomorrow. At least now I am fairly confident that I am not going to loose my engine while on a trip with my wife. I was afraid of being 50 miles from nowhere and broke down with my wife screaming at me.
I have graphite spray, it is wise to lube the rollers and sliding surfaces with it (clutches)???? I'll give it the heat test tomorrow.
At first my wife was harping on me about always working on "that Yamaha" and it's turned into, "When are you coming in the house to spend time with the kid." Jeesh. 88mph is fast enough when riding with the wife, but the thought of why is racking my brain and made me nervous about a failure. I've never been stranded riding the Blue in my life, so I don't want to start now.
I also was wondering about the belt and clutches. I might have to look into that tomorrow. At least now I am fairly confident that I am not going to loose my engine while on a trip with my wife. I was afraid of being 50 miles from nowhere and broke down with my wife screaming at me.
I have graphite spray, it is wise to lube the rollers and sliding surfaces with it (clutches)???? I'll give it the heat test tomorrow.
At first my wife was harping on me about always working on "that Yamaha" and it's turned into, "When are you coming in the house to spend time with the kid." Jeesh. 88mph is fast enough when riding with the wife, but the thought of why is racking my brain and made me nervous about a failure. I've never been stranded riding the Blue in my life, so I don't want to start now.
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Do NOT lube the clutch. You can clean it, but don't lube it.jholden said:
And those compression numbers only appear low. My gauge on a fresh rebuild gave me exactly what you got. Its all about the gauge.
If you change the belt, make sure you wash it in hot soapy water and break it in slowly. Don't slap it on and go and do 5 hard pulls. Give it at least 20 miles to stretch.
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do not put graphite spray................................................it stick so mutch ,,,clean and don't put nothing
bluemonster1
LIFE MEMBER ONLY ONCE!!!
I know..I know.....it's hard to get away from that Yamaha...
yeh,the thing with the wife could be a problem for you.Mine always tells me I spend to much time on the sleds and computer..and not enough with her.Might be some truth in that.She works night shifts and basically I don't see her much anyways.But could be an issue when you have small children.
yeh,the thing with the wife could be a problem for you.Mine always tells me I spend to much time on the sleds and computer..and not enough with her.Might be some truth in that.She works night shifts and basically I don't see her much anyways.But could be an issue when you have small children.
bluemonster1 said:
i'm gonna have a little girl soon soon so i need to do has mutch a possible for now lolll
modsrx said:
congrats man. My little daughter is 8 weeks old. It's our first and it is an amazing experience. This coming weekend my wife and I are celebrating our first time away riding together this year and marks the last weekend before she returns to work. I want things to go well since I think she'll be worried about the baby with my mom enough.
I won't spray anything on the clutches. I will pull off and wiping them down. PV adjustment seemed fine. I am going to put in some new BR9ECS plugs, and wipe down the clutches. Now if I could only find the muffler spring that flew accross the garage, I'd be greatful.
Thanks for all your help guys. I know there are repeated questions on the site day in and day out about compression/PV/Clutching, but tonight may have been more about moral support. Thanks again
VenomMod
New member
Is this the weekend you're supposed to come up here and ride? If so get hold of me. I'm looking to go out for a little ride. Just have to pry myself away from the grips of the girl friend.
jholden,
you haven't been married long enough! 1) you notice her harping, 2) you know what she's harping about 3) you seem to care!
I'm lucky that my wife isn't interested in riding. If you break down on the trail and she starts screaming at you, just point out to her how many witnesses are around or comment about how hard it would be to find a body out there. LOL
My daughter just turned 12. The only reason I bout my sled is so that I can spend time with her. Enjoy them when they're young because they grow up so darn quick!
you haven't been married long enough! 1) you notice her harping, 2) you know what she's harping about 3) you seem to care!
I'm lucky that my wife isn't interested in riding. If you break down on the trail and she starts screaming at you, just point out to her how many witnesses are around or comment about how hard it would be to find a body out there. LOL
My daughter just turned 12. The only reason I bout my sled is so that I can spend time with her. Enjoy them when they're young because they grow up so darn quick!