Viper engine tune

[DT]

I have a '15 Viper RTX-DX, with 900 miles now, that has engine tune issues similar to what people with the '14 models were reporting; misfiring, popping, hard starting. I haven't heard another Viper personally so I don't have anything to compare to. Maybe this is the way they all run, dunno. It runs perfect other than this. I just took it to my dealer to see if there's anything they can do, thought I'd post this and will update when I hear back from them. Here's a video so you can see/hear what I'm referring to-

 

[WVTurboLTX]

Doesn't sound any different than the 3 stock ones that I rode with.

 

[cannondale27]

Yup thats what we were able to clean up with PCV.

 

[DT]

Like I said, I've not heard another Viper personally. A lot of people talk about this here, but I couldn't find any video, so thought I'd post mine. My phone recording softens the sound of the back firing but if you listen carefully, the deep sounding puffs are actually a harsh "popping". So this is common, I thought the 15's were supposed to not do this?

Cannondale, can you point me to info on this PCV fix? My dealer looked at my sled, running it in the parking lot and having it lurch on him, admitted it wasn't right. I don't know where this will go, but I'd like a back-up plan if Yamaha won't fix it.

-thanks

 

[stingray719]

Neither of ours do that, but we are at higher altitude and our sleds run a bit richer up here.

 

[cannondale27]

Like I said, I've not heard another Viper personally. A lot of people talk about this here, but I couldn't find any video, so thought I'd post mine. My phone recording softens the sound of the back firing but if you listen carefully, the deep sounding puffs are actually a harsh "popping". So this is common, I thought the 15's were supposed to not do this?

Cannondale, can you point me to info on this PCV fix? My dealer looked at my sled, running it in the parking lot and having it lurch on him, admitted it wasn't right. I don't know where this will go, but I'd like a back-up plan if Yamaha won't fix it.

-thanks

Its a PowerCommander fuel tuner. Some of us just richened it up a bit at around 2000-2500 to get a nice clean idle. Erratic idle has got to be the most common complaint after reflash. It does get better after a few hrs but never idles same as before reflash. Depending on your mods it can be really bad to point of it not even being able to move out of trailer. Hope Yamaha gives us a decent reflash maybe one with more power as a reward for putting up with some of these issues!

 

[DT]

Thanks guys. Yeah, I'm usually riding in the UP so we don't have much altitude. These sleds have been out for 2 seasons now. It's hard to believe they would still have running issues.

When it's burbling, I don't have a problem getting it to go, it's getting it to go easy. On a good slippery surface, I have to keep one hand on the brake or the sled will lurch several feet. Makes it difficult for simple maneuvering.

When I talked to my dealer about this yesterday, he said they had not had one "idling" complaint on the '15s but had done a lot of reflashes on the '14s. He could be blowing smoke but he did admit to the 14s so this makes me wonder??? Are you guys saying your 15's do this?

Cannondale, I looked at the website for these PowerCommanders. I hadn't planned on modifying this sled like I typically do but a couple hundred for a tuner wouldn't bother me too much. If you don't mind, which model are you referring to?

 

[cannondale27]

http://www.powercommander.com/powercommander/
PCV
Ulmer,Hurricane and other site sponsors have them with maps and probably some advice on how to fine tune. The thing is this wierd idle and rough low speed is not the same among all the sleds from what I have seen. For instance mine was much less a issue than what NosPro had. I believe NosPro has a post on this issue also.

 

[Jeepjklabrador]

Mine does the same dont really bother me ....waiting for the reflash

 

[Nytros rule]

http://www.powercommander.com/powercommander/
PCV
Ulmer,Hurricane and other site sponsors have them with maps and probably some advice on how to fine tune. The thing is this wierd idle and rough low speed is not the same among all the sleds from what I have seen. For instance mine was much less a issue than what NosPro had. I believe NosPro has a post on this issue also.

Both of my/our sleds were ref lashed at the same time, mine starts better, runs smoother but doesn't make as much power.

 

[stingray719]

Both of my/our sleds were ref lashed at the same time, mine starts better, runs smoother but doesn't make as much power.

When we did ours, they tried on the second sled and it wouldn't redister the serial number so they were going to enter the serial number manually. I aske them to reboot the laptop and then it read the serial number on the second sled right. Wonder if you had something like that happen on yours?

 

[NOS-PRO]

http://www.powercommander.com/powercommander/
PCV
Ulmer,Hurricane and other site sponsors have them with maps and probably some advice on how to fine tune. The thing is this wierd idle and rough low speed is not the same among all the sleds from what I have seen. For instance mine was much less a issue than what NosPro had. I believe NosPro has a post on this issue also.

Yes, took quite a bit of fuel between 2,700-3,250 to clean up the rough idle, backfiring and popping during engagement. Powercommader changes made engagement smooth again.

Both of my/our sleds were ref lashed at the same time, mine starts better, runs smoother but doesn't make as much power.

I noticed a power and speed decrease also.

 

[Nytros rule]

When we did ours, they tried on the second sled and it wouldn't redister the serial number so they were going to enter the serial number manually. I aske them to reboot the laptop and then it read the serial number on the second sled right. Wonder if you had something like that happen on yours?

Tried to have my wife's redone.
Computer said "software up to date no up dates available".

 

[DT]

Thanks guys for your input. From what I'm seeing, most of you have the '14s with a reflash. Does anyone have a '15 that runs like this? Either way, I should here back about my sled this week and will post their response on it.

Again, as shown in my video, this thing lurches when it finally smooths out after the burble, that starts around 2700rpms. When it does this, I'm not jabbing the throttle. I'm only pushing it just far enough to get it to move. My sled lurches hard enough that I can't even tell what rpm clutch engagement was.

 

[stingray719]

Yes, took quite a bit of fuel between 2,700-3,250 to clean up the rough idle, backfiring and popping during engagement. Powercommader changes made engagement smooth again.



I noticed a power and speed decrease also.

And that is what is strange about this, both mine it raised the rev limiter and they both run noticeably better. Might be from being at higher altitude I am not sure but the flash helped both ours.