Guy really need some help here. I just had a new piston put in my magnum cause the i call it a skirt was broke my piston. Anyway even before then I had trouble with card. When I first start it when its cold it runs fine.but after 10 minutes when its warmed up and sits there and ideals when I go to give it throttle it bogs and stalls. It will start right back up again but will do nthe same thing enless i feather the throttle fast and then it will drive and be fine till I let off it again.. I paid $667 dollars to have this worked on. What could be the issue???

 

This could be anything from a carb problem(if it wasn't rebuilt) a worn cam problem if this wasn't checked /replaced on the rebuild, to a fuel pump issue,electrical break down. Several things that could be causing this when it gets warm. Plus if if was bored too much as I've seen some do the rings could be loosing pressure against the cylinder walls. Piston to cylinder clearance should be .0006 to .0018 on the bore. .0024 is considered at the service limit. Here's a link to a pdf service manual that can help you eliminate one thing at a time.Index of /ORV Manuals/Polaris/1996-1998 - All Models

 

I forgot to mention that I do smell gas while idling also ..like maybe its getting to much fuel.. But as long as i dont stop completly it seems to run fine. But as soon as i let all the way off the gas and try to go again it just dies. But will start right up again and i have to feather the throttle then its fine on the move...

 

Then start at the carb. If a carb kit wasn't installed,there are plenty on Ebay. Manual will show you the on the carb repair,float setting.Plus Shindy has cheap kits.Not listed,but I believe #03-416 is the correct kit for the 425. Give em a call. Shindy ATV Carburetor Repair Kits - SHINDY-ATV-CARBRPRKIT

 

i found this one one ebay..would it work...
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Have one to sell? Sell it yourself

Polaris 425 cc Magnum ATV 2x4 4x4 6Sig Custom Carburetor Carb Stage 1-3 Jet Kit..



http://www.ebay.com/itm/Polaris-425-cc-Magnum-ATV-2x4-4x4-6Sig-Custom-Carburetor-Carb-Stage-1-3-Jet-Kit-/230853279469?pt=Motorcycles_Parts_Accessories&hash=item35bfed7eed&vxp=mtr

 

On most of these jet kits regardless of what they say,you're mainly paying for the thinner titanium jet needle and carb jets are remarked with their own numbering system. Just like Dyno jet kits. You can pay 35 bucks for this or a Shindy carb kit is about 17 bucks. Plus without any modifications to the exhaust or air intake,the kit wouldn't help that much on added power.

 

so your saying I would be better off buying the Shindy carb kit instead of the one one ebay? I bought a brand new carb for it but when the shop worked on it they said the new carb didnt work. thats why they put the old carb back on.The new carb i had to close off the snorkle boot with a tie wrap to cut the air flow off. and it ran ok..but ended up using the old one after they rebuilt the engine.Maybe the new one was jetting wrong?

 

You may have gotten the 40 mm carb instead of the 34 mm carb your model takes? Standard jetting is a 140 main jet and 40 pilot jet for the Magnum.Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse
Plus you can look in the carb section of this service manual for your model as to any changes in jetting that may be required for altitude and temperature.Index of /ORV Manuals/Polaris/1996-1998 - All Models
Having to clamp down the snorkel boot for it to run sounds like the jetting is lean,plus do you have the foam prefilter on the snorkel? http://www.cyclepartswarehouse.com/f...1996&fveh=5417