2 stroke quad help

[ant_mb]

Hey Guys,

This is a 2003 Yamaha blaster.

I pulled my head today to install a Wildcard Racing modified head. This is what my piston looks like.

I have about 30 hours on a complete rebuild. Is this normal? I did a leakdown test and made sure to jet properly. I fouled 3 plugs on the break in. What do you guys say?

here is my sexy new head. lol

 

[champion221elite]

That amount of carbon on your head looks pretty normal to me. I'll copy your photo and post it on an outboard engine site that I hang out on. I'll get back with you regarding their response.

What kind of 2 stroke oil are you burning, and what ratio are you mixing at?

Do you run any sort of carbon cleaner/preventer in your fuel? I've found that running Seafoam in every gallon of gas through my Mercury 225 EFI helps keep the fuel system clean and the engine as well. My heads, piston crowns, spark plugs and fuel injectors stay much cleaner. Another benefit to running a carbon cleaner is reduced chances of "ring jacking". This is caused when carbon gets behind the piston rings and forces them outwards. If the ring gets pushed outward too far, it can catch on your exhaust port and will rip the ring out which will in turn scratch the hell out of your cylinder bore.

 

[ant_mb]

That amount of carbon on your head looks pretty normal to me. I'll copy your photo and post it on an outboard engine site that I hang out on. I'll get back with you regarding their response.

What kind of 2 stroke oil are you burning, and what ratio are you mixing at?

Do you run any sort of carbon cleaner/preventer in your fuel? I've found that running Seafoam in every gallon of gas through my Mercury 225 EFI helps keep the fuel system clean and the engine as well. My heads, piston crowns, spark plugs and fuel injectors stay much cleaner. Another benefit to running a carbon cleaner is reduced chances of "ring jacking". This is caused when carbon gets behind the piston rings and forces them outwards. If the ring gets pushed outward too far, it can catch on your exhaust port and will rip the ring out which will in turn scratch the hell out of your cylinder bore.

Thanks for the help man. I am running 2 stroke Yamalube at a 24-1 ratio. My first 3 plugs fouled out so I switched to Iridium and haven't fouled one in 25 hours of use. The quad runs like a beast for a 200 with a 250 pound rider on board. It will easily outrun a 400 ex(my friend rides one) through the first 5 gears. He catches up and gets me on the top end, but we are rarly there so I'd prefer the 2 stroke power.

 

[champion221elite]

24:1 sounds like way too much oil. What ratio did the stock Blaster engines run?

 

[ant_mb]

Stock it has a oil injection system that reportedly mixes at 20-1. I took it out on my rebuild and pre-mix at 24-1 to be on the safe side. Most guys are mixing 32-1 on another site, but from all I read it continues to make increasing power up until 20-1 then drops off. I figured 24-1 would be a great compromise?

 

[champion221elite]

24:1 is way overkill for oil... it's no wonder why you fouled 3 plugs during the break-in.

32:1 sounds plenty safe, especially if you switch to a high quality synthetic oil. You'll get less carbon, less smoke, and your quad might even run better.