no_dice6
New member
Looking for some help from the gurus. I'm currently running a 2003 Viper with an 835 Bender that is set up for about 7,000 to 10,000 feet. There are times when it would be nice to ride it around 3,000 to 4,000 feet. I have owned this sled for a couple years and have had no problems whatsoever. The previous owner had told me that it was case ported, but he was running the stock size carbs. He had run the recommended big carbs for it but liked the stock carbs better. I picked up a spare rack of stock Viper carbs on ebay for like $30 and would like to jet it for the elevation stated above. I had called Bender and there recommendation was 170 main and 65 pilot. Does this sound like it is in the ballpark to anybody else? Here is another thing. I had tried putting a 65 pilot into the carbs tonight and they will not fit. The projected area of the pilot jet with the emulsifier holes in too large in OD. I know someone will ask me what jet sizes are currently in the sled that is set up for high elevation. The answer is that I do not know at this time. I am too lazy as of tonight and the garage is too cold for me to get that answer today. Any recommendations or opinions are welcomed. Thanks
We can wait till spring i guess........ might be fine with what you have already........
no_dice6
New member
Not sure what help that was. Jetting will not be fine for 3000 feet as it currently has good plug color at 7000 feet.
staggs65
Moderator
look up buffalobob in the member list. he runs those big benders. maybe he would help you out
65 Pilots
WOW! That is huge! I find it hard to believe even though I have absolutely no experience whatsoever w/ a bender 835.
Madmatt
WOW! That is huge! I find it hard to believe even though I have absolutely no experience whatsoever w/ a bender 835.
Madmatt
valin
Active member
Madmatt said:
You find that huge?
A stock Mach Z runs 290 or 300 main jets. I run roughly 450's in my trail 780, and roughly 680's in my race sled
Yup
Forgive me Valin I know and I'll be the first to admit that I am completely a novice tuner compared to you. But who cares what the mains are in a Mach Z? We're talking about a Yamaha and we're talking about the pilots here, right? Seems like the 45's in your trail 780 might be a reasonable comparison but wouldn't you agree that 65's are pretty much huge compared to 45s? And as far as your race sled is concerned what size is that engine?? And it's a RACE sled.....and I'll admit an awesome one at that....you do some really impressive work. But yes, on an 835cc trail engine with 33mm carbs I find 65 pilots to be HUGE!
Madmatt
valin said:You find that huge?
A stock Mach Z runs 290 or 300 main jets. I run roughly 450's in my trail 780, and roughly 680's in my race sled
Forgive me Valin I know and I'll be the first to admit that I am completely a novice tuner compared to you. But who cares what the mains are in a Mach Z? We're talking about a Yamaha and we're talking about the pilots here, right? Seems like the 45's in your trail 780 might be a reasonable comparison but wouldn't you agree that 65's are pretty much huge compared to 45s? And as far as your race sled is concerned what size is that engine?? And it's a RACE sled.....and I'll admit an awesome one at that....you do some really impressive work. But yes, on an 835cc trail engine with 33mm carbs I find 65 pilots to be HUGE!
Madmatt
valin said:You find that huge?
A stock Mach Z runs 290 or 300 main jets. I run roughly 450's in my trail 780, and roughly 680's in my race sled
Buddy of mine has a 990 cat motor that uses a 600 at 10,000 ft. We are contemplating setting it up to run here in MN, but are not sure if the 40 mile range would be worth the hassle. Might take it hill dragging this spring though.
valin
Active member
Madmatt said:
Matt, I think you are misunderstanding the post that I made, or are missing the point. In his first message, he inquired not only about the pilot jets, but also that Bender recommended 170 mains. What I posted about the setup that I am running was a relation to what a stock 150ish hp sled (mach z in this case) would run for jetting, as opposed to my 780, which makes about 180hp. The fact that it happens to be a relation to a mach z is really irrelevant. Obviously, there is a large increase in main jet size (roughly 15 sizes), so I am not surprised that they are recommending 170's. Who cares about information like this that shows the relation of fuel required for a motor that makes comparable power?....maybe the person who is looking for the information, as the post was only directed towards him in the first place.
As far as the 65 pilots go, I would not say that they are excessively huge for an 835. With the 33mm carbs, I would have guessed 60-65's.
mopar1rules
Active member
you said that your 65 pilots won't fit. are they the same series as the stock pilots? are you accidently trying to install the wrong series pilots into the stock 33's?
no_dice6
New member
They appear to be the same exact same style of pilot jets. The bottom of the pilot with the emulsifier holes has the same wall thickness when comparing the 45 pilot and the 65 pilot. A direct comparison would be like comparing 4" schedule 40 pipe and 5" schedule 40 pipe. They have the same wall thickness, but different ODs. I was going to take some drill bits to try and get a measurement of the area that the pilot jet sits into, but of course my drill bits that are that approximate size are broken. Here is one thing that I will edit from my original post. I had stated that Bender recommended 170 mains and 65 pilots. I relooked at what I had written down yesterday and Bender had actually recommended 60 pilots. My little pea brain could not remember that information. I'll just get over my laziness and tear the high elevation carbs off of my sled and then jet the mains up one or two sizes and then play with the air screw adjustment to determine the correct pilot jet size. I am making some remote air screw adjusters, so that procedure should not be too difficult. Once I tear my old carbs off, I will post the jetting that is set up for high elevation and post what my jetting will be for 3,000 feet so future searchers can find that information.