need help in resolving a bog issue

[knee deep in it]

2007 600 HO carbed. Union Bay porting, SLP pipe can, V force 3 reeds, SLP high air flow horn + dash vents. 410 main jets.

Last year, I had a bad bog at elevation. . Over the summer , I increased the jetting by three sizes to 410. Last week, we went ditch banging and it ran perfectly. We were at 3400 feet elevation.

This week , we staged at 4650 feet. As I gain elevation, I develop a bad bog. It starts at low mid range and stops me from hitting high rpm (6500 max). The bog got real bad at 5300 feet. In the attached video, I tried the choke near the end and it pretty much killed the engine, made the bog much worse.

http://vimeo.com/17744295

At lower elevations, it is much better, very crisp. Given the fact that the choke made it worse, am I too lean or rich? Should I go up or down n the needle valve and or main jet.

When a sled starts to bog when you gain elevation, are you generally too rich or too lean?

 

[Jonce]

Generally speaking:
Lower elevation = bigger main jet
Higher elevation = smaller main jet

You may want to look into the ATACC system for your sled.

 

[knee deep in it]

i actually dont have an aatac system on this sled (2007 RMK) but you give me an idea. I am building a 730 from a 600 that was turboed. The 730 setup calls for bored carbs. This sled has bored cardbs and the carbs that were going to go into the 730 has PowerJets from Thunder Products.

Maybe I will use the carbs from that project.

 

[dexter]

you went the wrong way with the jetting, lean it out. be sure to check plugs as u do this, no sense burning it up.