I've got this problem with my 2004 Mtn Viper. Recently, I installed slp triple pipes. I changed the jets and clutching as was recommended. I got it running normally, or so I thought. Hill climbing i some deep powder it ran well for a little while, then it began performing poorly. I shut it off for a couple of minutes. It was very difficult to re-start. Once I got it started, I went for the hill again. It performed perfectly. When I shut it off again, it was hard to start. Any suggestions? Thanks
Mountain Viper question
- Thread starter smokenjay
- Start date
If you were running in deep powder and it was dumping inside the hood, you could actually be cooling the pipes enough to bog the motor. Cold pipes richen the motor. Try some powder mesh in your hood openings.
As far as the hard starting, check your pilot jet. I run a 60 pilot in my piped Viper and have no starting issues.
As far as the hard starting, check your pilot jet. I run a 60 pilot in my piped Viper and have no starting issues.
2004 MNT Viper
You are probably having the "bogging" problem that alot of viper owners have. As mentioned, snow on the pipes cools them off quickly. Check a posting on Totally Yamaha about the MNT Viper BOG, under SXR/SX Viper sub forum.
As for me, I bought a 2004 MNT Viper that was modded up in Sept. 2007.
The sled has entire under hood air closed off. NO BOG ISSUES with my sled.
The only thing I did was ceramic coat the triple CPR Simmons pipes that fall, plus installed Ohlins in the rear suspension. My sled has the ATTAC installed so right now I do not recall the main jets but it runs sweet around home (1500-2500ft) and in the mountains as well. The motor has a Peak Head with custom cut domes to match the motor porting and weighed/balanced, trimmed & windowed pistons. I running the set of domes that I do not need to mix AV GAS with premium fuel. If I want more in the moutains then I just change out the domes and still run Premium fuel.
As for hard starting...kind of a common thing with triples (my ZRT 800MC) did the same thing when warm. Hold the throttle open a bit and it should help. Start on first pull.
You are probably having the "bogging" problem that alot of viper owners have. As mentioned, snow on the pipes cools them off quickly. Check a posting on Totally Yamaha about the MNT Viper BOG, under SXR/SX Viper sub forum.
As for me, I bought a 2004 MNT Viper that was modded up in Sept. 2007.
The sled has entire under hood air closed off. NO BOG ISSUES with my sled.
The only thing I did was ceramic coat the triple CPR Simmons pipes that fall, plus installed Ohlins in the rear suspension. My sled has the ATTAC installed so right now I do not recall the main jets but it runs sweet around home (1500-2500ft) and in the mountains as well. The motor has a Peak Head with custom cut domes to match the motor porting and weighed/balanced, trimmed & windowed pistons. I running the set of domes that I do not need to mix AV GAS with premium fuel. If I want more in the moutains then I just change out the domes and still run Premium fuel.
As for hard starting...kind of a common thing with triples (my ZRT 800MC) did the same thing when warm. Hold the throttle open a bit and it should help. Start on first pull.
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Ive got 04 viper
I had the same prob but found simple fix was to remove right sceen on dash the small one and add a outer wear to the air box ! boy you can sub your sled in the steep and deep works so mutch better i was going to get rid of the sled over it my mm dont do it and ps dont do it but it did if i woundnt have found the fix was going to give it away and yes give little fuel on restart
I had the same prob but found simple fix was to remove right sceen on dash the small one and add a outer wear to the air box ! boy you can sub your sled in the steep and deep works so mutch better i was going to get rid of the sled over it my mm dont do it and ps dont do it but it did if i woundnt have found the fix was going to give it away and yes give little fuel on restart
It's not so much the cooling of the pipes, as it is the stream coming off of them and getting sucked into the intake. I ran mine with no vents at all to keep the pipes from overheating under the hood. Worked great in deep pow!
But you must close off ALL the underhood air inlet into the chamber above the air box. Then install some flowrites, and drill some extra holes in the cowl behind the windshield. For a cold air intake set-up. Also don't forget to jet up 1 or 2 sizes richer, when going to a 100% cold air intake set up. Pay close attention to the Mag plug plug color. It's usaully the first one to go lean on piped Vipers. I ran the Mag one size richer and 1/2 postion richer on the needle.
But you must close off ALL the underhood air inlet into the chamber above the air box. Then install some flowrites, and drill some extra holes in the cowl behind the windshield. For a cold air intake set-up. Also don't forget to jet up 1 or 2 sizes richer, when going to a 100% cold air intake set up. Pay close attention to the Mag plug plug color. It's usaully the first one to go lean on piped Vipers. I ran the Mag one size richer and 1/2 postion richer on the needle.
M
Mcx Nytro
Well-known member
One other thing not mentioned here is to make sure your pipes are sealed at every joint..not leaking out used up air and going into the airbox.....02
Thanks!
Thanks for the advice everybody. I am going to try changing the air intake setup first, as I am fairly confident that the carbs are set up correctly. I will also check the seals around the pipes. I'm going riding in a couple of days, so I will let you know how it goes. Thanks again!
Thanks for the advice everybody. I am going to try changing the air intake setup first, as I am fairly confident that the carbs are set up correctly. I will also check the seals around the pipes. I'm going riding in a couple of days, so I will let you know how it goes. Thanks again!
Worked great. Thanks.
