So.... back to stock head... right????
I'd like to ride with ya this season!!!
No SHEEEEEET Gril!!!!
Why does ring locating pin fall out?
- Thread starter mc2stroke
- Start date
No SHEEEEEET Gril!!!!
L
Deto makes pretty good sense as the cause of the pins falling out. When deto happens it blast away the boundary layer protecting the piston from direct combustion temps of 2000 + degrees which is why bad deto makes all those interesting holes.
The piston and dome will get hotter and when its hot enough the aluminum up at the dome area will start to soften and then I'd guess lose its grip on the pins.
The pins are right up at the dome which is the hottest area.
Anybody ever notice if they have two ring pistons if its always the top ring pin that comes out?
I have never had a pin on Wiseco's come out and have run them for many years. But I don't subscribe to the high-compression makes up for high altitude belief of most people. Really high compression boost mid range but hurts top rpm HP because it takes heat away from the pipe making sound waves operate at lower speed which makes it act like a longer pipe, lowering the rpm it tunes to for peak HP. Lower peak RPM, your air pump (cylinders) may likely be pumping less air in and out, less air means less oxygen and fuel being burned making less HP.
Good Luck
Another thing is this 800 had porting which increases the "Running Compression" because the cylinders were filled with more fuel air mix so it in effect had two compression increases, if it also had twin pipes added, would have been three. SLP used to have some real interesting tech pages on Running compression showing the difference between single pipe versus twins and fuel requirements with or without static compression increases. Most guys don't realize you have look at this the same way you look at a motor when you start adding boost with a turbo.
The piston and dome will get hotter and when its hot enough the aluminum up at the dome area will start to soften and then I'd guess lose its grip on the pins.
The pins are right up at the dome which is the hottest area.
Anybody ever notice if they have two ring pistons if its always the top ring pin that comes out?
I have never had a pin on Wiseco's come out and have run them for many years. But I don't subscribe to the high-compression makes up for high altitude belief of most people. Really high compression boost mid range but hurts top rpm HP because it takes heat away from the pipe making sound waves operate at lower speed which makes it act like a longer pipe, lowering the rpm it tunes to for peak HP. Lower peak RPM, your air pump (cylinders) may likely be pumping less air in and out, less air means less oxygen and fuel being burned making less HP.
Good Luck
Another thing is this 800 had porting which increases the "Running Compression" because the cylinders were filled with more fuel air mix so it in effect had two compression increases, if it also had twin pipes added, would have been three. SLP used to have some real interesting tech pages on Running compression showing the difference between single pipe versus twins and fuel requirements with or without static compression increases. Most guys don't realize you have look at this the same way you look at a motor when you start adding boost with a turbo.
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C
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piston pin
I just had this happen on 670 split second engine with wisecos.thanks
I just had this happen on 670 split second engine with wisecos.thanks
C
my pin was pushed in and resulted in the replacement of cylinders and piston on my 800R. ~1800km
completely stock, 91 octane shell fuel (no ethanol). How would have have detonation? Running br9es vs. br9ecs??
completely stock, 91 octane shell fuel (no ethanol). How would have have detonation? Running br9es vs. br9ecs??
Could just be bad luck... Poor fuel quality resulting in Deto...
BRP had NGK develop the 'ECS' plug to help with detonation back in 01 with the first generation 800's.
L
Have heard of some shops setup secret for 800R's is narrowing the goofy wide squish band to slow down deto in stock motors.
Good Luck
PS The stock doo Series III engines all have what I consider the worst combustion chamber design (Top Hat) of any snow engine. The best chamber design was the old 670 (Hemispherical) which is basically what all the aftermarket heads have.
Good Luck
PS The stock doo Series III engines all have what I consider the worst combustion chamber design (Top Hat) of any snow engine. The best chamber design was the old 670 (Hemispherical) which is basically what all the aftermarket heads have.
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Norway, Thank you for answering the canuks dumb question.. !! lol
At least the guy from overseas knows what happens when you mix lean midrange with groomed trail canada riding...DETO !
Why do so many quebecers ride YAMAHA ?? their trusty DOOS overheat and seize at the worst times..
And the ecs series was a YAMAHA first, btw. they make 3-4 hp more than a std es plug in every engine I've dynoed.. every single one.
Hemi heads are not std on doo series three engine, hemi heads do NOT have the torque production of the std torroid used on the 600 ho.
All the heads on the DOO snocrossers are torroids, and boy do they work great.
I even use torroids in the turbos to keep the squish area cooler. works for me and my customers.
Gus
At least the guy from overseas knows what happens when you mix lean midrange with groomed trail canada riding...DETO !
Why do so many quebecers ride YAMAHA ?? their trusty DOOS overheat and seize at the worst times..
And the ecs series was a YAMAHA first, btw. they make 3-4 hp more than a std es plug in every engine I've dynoed.. every single one.
Hemi heads are not std on doo series three engine, hemi heads do NOT have the torque production of the std torroid used on the 600 ho.
All the heads on the DOO snocrossers are torroids, and boy do they work great.
I even use torroids in the turbos to keep the squish area cooler. works for me and my customers.
Gus
Hey Gus,
This is probably a dumb question, but is the stock 800HO style head the "torroid" style head you are referring too? I'm confused….
Everyone else- I was not using a stock style of head when I killed the motor again. It was an aftermarket Hemi style head. BUT the squish was still much tighter then a stock head, I think.050 and I am thinking fuel quality may have been in issue (too low of octane???). I need to send everything back so it can be evaluated by the guy who helped me build it and I will try to report back on the confirmed cause of the motor falling apart.
I did not tell everyone what I was exactly running because I do not want to hear a bunch of bashing of this guy or that guy. Both time I have put this together I have used different pistons but the same result, the locating pin falls out after I have ran 1200 miles (the first time) and 2400 (the second time) miles. So, "I think" this tells me that the motor build is getting closer to what I require but it is still to on the verge of killing it self at times… What is causing that… Poor fuel, too much compression, me being a bone head… We shall have to wait and see…
Right now, we are cleaning it up the motor and going to running all stock parts…. I need to ride baby…
L
Your right lean mid range also but add in the combustion chamber design also. Higher squish velocity of Top Hat stock head requires bigger jets. One of Kelsey setup parameters is leaner jetting. Its because more reasonable head design.
I don't except stock jetting main or needle on anything, always go a bit richer and work down. Can't believe anybody else would not do this, especially with EPA regs.
Good Luck
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been following this thread since Ive just had a pin in SPX piston make my life
less enjoyable.
Gus whats with the spark plug ??? 3 more hp ! Why are we not all running this plug ?? its $11 Canadian but who would care if its 3 hp. please enlighten me.
less enjoyable.
Gus whats with the spark plug ??? 3 more hp ! Why are we not all running this plug ?? its $11 Canadian but who would care if its 3 hp. please enlighten me.
N
......I did not tell everyone what I was exactly running because I do not want to hear a bunch of bashing of this guy or that guy. Both time I have put this together I have used different pistons but the same result, the locating pin falls out after I have ran 1200 miles (the first time) and 2400 (the second time) miles. So, "I think" this tells me that the motor build is getting closer to what I require but it is still to on the verge of killing it self at times… What is causing that… Poor fuel, too much compression, me being a bone head… .....
Need more octane or less compression to cure the deto. Either that or rebuild it every 1000 miles as preventative maintenance and run it as is.
NSC
G
Thats is what I have been seeing since I first had the pleasure of testing a set in the 1997 sx 700 and 600 that we raced on grass.
When I look at what might be the reason I can only surmise that the flame kernel is better and is easierto keep kool.
Other than that I don'tknow why, just that even the 1404's show 4 hp just tossing in properly gapped ecs plugs..YES I DO GAP THEM PER APPLICATION>
Don't be skeeered,, set them just like any other plug and go.
No , the 800ho head is NOT a torroid. There are many differing versions of torroids and hemi's. Some work better than others and in differing rpm ranges.
I don't subscribe to the one head is superior school, sorry. Each has its merits and its weakness that has to be weighed for your end use.
Tight squish USUALLY reduces edge gas temps as they are basically nonexistent in that design, the bad is that we lose pipe energy with this design. OK, less deto and less power ??? hum....
get some back with compression, that too takes away from the peak rpm, calculate your gains to your losses and then decide.
Torroids present the spark plug tip deeper into the combustion pocket, they also have an effect on the loop scanvenge path and its density.
Hemi shapes effect these parameters diffently ,some good some not so good.
torroids are not curealls, neither are hemis. just differing paths to the same end.
Gus
D
the story i heard was the ECS plugs effectively act like they advance the timing.
So, if you make dyno runs and compare plugs, you can get different horsepower numbers depending on how you set the timing.
On the pins, I used to run a Carl's 760. They were notoriously bad for detonation as they ran twin pipes, lots of compression, and lots of timing. We ran 30 to 50 percent AV gas in them.
Sooner or later customers would do something to get detonation on them, or burn them down, myself included. Once I put 50 percent pump gas in and then I put 50 percent pump gas in. It detonated BAD, Pins were fine, but top of piston was chowed out.
Another time I melted the piston until the pin came out the top of the piston and stuck in the head.
I asked Jack from Carl's what he did to keep the relocated pins in place, and he gave me that goofy smile, and then told me. Pretty ingenious, and this is why the big bores Carl's uses don't have pin relocation issues.
So, if you make dyno runs and compare plugs, you can get different horsepower numbers depending on how you set the timing.
On the pins, I used to run a Carl's 760. They were notoriously bad for detonation as they ran twin pipes, lots of compression, and lots of timing. We ran 30 to 50 percent AV gas in them.
Sooner or later customers would do something to get detonation on them, or burn them down, myself included. Once I put 50 percent pump gas in and then I put 50 percent pump gas in. It detonated BAD, Pins were fine, but top of piston was chowed out.
Another time I melted the piston until the pin came out the top of the piston and stuck in the head.
I asked Jack from Carl's what he did to keep the relocated pins in place, and he gave me that goofy smile, and then told me. Pretty ingenious, and this is why the big bores Carl's uses don't have pin relocation issues.
M
ring pin
Wiseco pistons have had this problem for 20 years atleast some things stay the same.
Wiseco pistons have had this problem for 20 years atleast some things stay the same.
D
X
mc2stroke, your problem is detonation. Yes, you could go back to the stock head, but then you just wasted that money (& power). Go to you closest dealer and have the timing backed off just a bit. Especially if this i a 800R motor. This will keep most of the deto under wraps. SLP recommends -2 setting on the 800R if running their head and pipe combo. It's hard to get rid of the deto without running lots of race fuel.
