Considering 14:1 piston

[wobble]

I think I'm having a head gasket issue. Last trip to the Oregon Dunes I noticed coolant coming out my overflow. It mainly did this while racing. I'm going to tear it apart again soon to deal with that issue. I'll send my head off this time to a machine shop to make sure it's flat and clean.

Some more history....the first trip after I finished my build in early spring, I went for a four day trip to the Oregon Dunes. I think I screwed up my power commander by loading the wrong firmware on there before the trip. This caused the power commander to obviously not work correctly. Because of this, my raptor was knocking and pinging like crazy the whole trip. I was chasing my tail trying to figure out what it was. Didn't figure it out for another month or so. (Thanks again Zebradog)

I think it may have damaged my piston, or worse.....my head, while running lean that trip. I need to tear it down to find out. It runs great, but I have a feeling something is wrong.

I'm thinking of going with a higher compression that my CP 11:1 piston while I have it apart. My question is for those who have a 14:1 piston installed. Have there been any problems with it? I'm concerned this is too much compression for a stock rod/crank to handle long-term. Any disadvantages (besides running higher octane, of course) I should know about?

I'll definitely go with some kind of aftermarket stud kit. I'm sure the OEM bolts won't handle this much compression, so I'll have to research the different options available.

My current mods are in my sig.

Thanks

[Colorado700R]

Hopefully Preddy08 will pop in to add his .02, but I think he's SB/SS with a 14-1 venom and he's had no issues (Except great performance).  Cam selection with high compression seems to a key factor as well.

talk to kenny about head gaskets/bolts to insure a solid build. 

[wobble]

Good point. I didn't even think about the cam. I really like my HC2 since I mostly ride trails. I need the lower-rpm power it provides.

[Sandeater]

Was the coolant bubbling in the reservoir tank or coming out of somewhere else?  Changed the coolant lately?  Fan coming on?

I am running the racers edge CP 14:1 without any problems so far.  Mine is an 06 and I don't wheelie much so haven't starved the crank bearings of oil and they are still holding.  I have about 30 hours on this piston already. 
Woke her up a lot!  I am going to run it til it locks up or wait a couple of years and tear it down and throw a stroker in there when doing an overhaul.

When we installed mine, we just used one OEM base cylinder gasket and OEM head gasket with some copper coat therefore putting the piston at zero deck or .015 in the whole, can't remember which one, to give more of a higher compression.  I am also running stock head bolts that have been torqued down 4-5 times.  I run 50/50 of 112 and 91 at 5500' or higher and 75/25 if I am running at 5000'.  Probably below 4500' i would run 100% race fuel.

[wobble]

Was the coolant bubbling in the reservoir tank or coming out of somewhere else?  Changed the coolant lately?  Fan coming on?

Yes, it's coming out of the reservoir. Had to add some coolant to the reservoir after a few hours of riding. I changed out the coolant to engine ice a couple months back when I did my clutch. I flushed the system well and put in the engine ice. Yes, the fan comes on quite a bit. No knocking or pinging anymore since I re-flashed the pc3 in June though.

[Sandeater]

Hmmm the only time I have had it boil in the reservoir was when the plug under the seat had came apart and I was running it hard up and down hill shoots and my fan never came on.  Does it do it every time you run it hard? Your thermostat might be stuck open. 

[wobble]

I'm not sure if it does it every time. I noticed it for the first time on my last dune trip. I had coolant on my precision stabilizer, steering stem, and on the inner part of my a-arms. I then noticed my reservoir was low. I'm going to take it apart anyway to make sure I didn't damage anything when I ran it for four days lean. Engine knocking and pinging for that long couldn't have been good on it. 

[Bert]

I had my tank off & when I routed the overflow hoses I messed up.  On a dune ride 1 hose ended up in my fan    My coolant was a bit low, I think it ran out the overflow hose.  Since then I've had the tank off & referred to the manual for proper routing.  Coolant levels fine for now.  I hope its not serious Wobble

[wobble]

I'll check that out. The last thing I did was replace the steering stem, so I was working in that area. However, since I ran it lean for that first dune trip, I'd like to check things out this winter to make sure everything is ok inside the engine. From what I've been told, it doesn't take long to damage things when you hear loud knocking and pinging. Since I have it apart, I just might have to do some kind of power upgrade.  :grin_nod:

[700crazzzynuttts]

Not sure what head gasket you are running, But I had had the same problem with the coolant coming out, no blowing out over flow, mostly while I was racing. That happened right after I had put 11:1 piston with wiseco gasket. As it turned out the wiseco gasket let go, changed out gasket with oem, have'nt had a problem since, it also seems to have increased compression and made it a lot snappier.

[wobble]

I'm using an OEM gasket. Never had this problem 'til this last trip. Something has definitely changed to cause it.