Bearings with pg turbo 1000

[product tester]

Kelsey not once did I say you lie or that you are up in the night I did how ever post that my statement was an opinion and you could take it or leave it.That is what I believe from my personal experiance.
If you dont like it then dont listen but your the one who called out lie not me I could care less if you believe me or not as you never listen to anyone but yourself no matter whos talking or what there talking about.
I have although pulled many turbos apart and many na sleds apart and the na sleds always show more heat marks around the rod bearings than the turbos What is the cause of this I dont know but I would say that If there are less heat marks then there would be less stress.

 

[deaner]

Kelsey not once did I say you lie or that you are up in the night I did how ever post that my statement was an opinion and you could take it or leave it.That is what I believe from my personal experiance.
If you dont like it then dont listen but your the one who called out lie not me I could care less if you believe me or not as you never listen to anyone but yourself no matter whos talking or what there talking about.
I have although pulled many turbos apart and many na sleds apart and the na sleds always show more heat marks around the rod bearings than the turbos What is the cause of this I dont know but I would say that If there are less heat marks then there would be less stress.

Just finished reading through this whole thread. Wow. Good debate.

Could the difference maybe be the fuel people use on each? People running turbos generally run REALLY good fuel right? Maybe that is the reason that they seem to hold up better vs. naturally aspirated big bores. If the majority of crank and rod failure is due to detonation, then having a high quality, consistent fuel like race fuel is taking this variable out of the equation. Even if the crank is seeing alot more stress due to the added power from the turbo, it is not seeing detonation........where the real damage is done. How many guys generally run straight race fuel in big bores?

Maybe Im way off base........its just a thought I had while reading through the thread.

 

[gus bohne]

Yes fuel quality is part of it, the other is oil volume and saturation.

what do you find when tearing down a turbo 2 stroke ?? lots of oil lots and lots of oil..
By sheer volume of fuel , there is lower temps in the bottom end and Better component life expectancy. Is oil blown off the surfaces, ?? no If it were the case it would happen regardless of boost and be more effected by rpm and the resulting increase in piston speed creating higher pumping aplitudes.

Suckin'' the oil right thru the engine and off all the internals...

Now,, do we do ourselves a disservice by premixing and over oiling the "combustion mix"? I do not mean the bottom end or ring and skirt lube, I refer to the contamination of the fuel with oil. ??

Would the pre set limit of the oem injection system give more room to the octane ceiling ? less oil burning would be better ?? or not ?

I've run both ways and seem to gravitate to premixing and even 40.1 .. where probably 70 .1 MIGHT,,MAYBE,, be its equivelent as we are burnign so much more by volume when premixxing...

But they do live long fruitfull lives at stupid boost levels so who cares !

Lots of good feedback here.
Gus

 

[scoop]

question

why is it recommended to run a extreem oil like red line in the turboed engines? Just a question???

 

[Radski30]

Lets put it this way radski and kelsey with a bb the or na motor the first thing you do is pin or weld the crank for durability. On the four strokes they do rods and pistions I dont know any two strokes that have diffrent rods.
I also dont know anyone that runs a turbo 2 stoke m series that welds or pins there cranks. I also dont know anyone that has a m turbo that lost a crank due to added power. on my mc 900 I never ran it lean not once I put good oil and mixed it 40 to one it was the most durrable na sled I ever had
only 1 900 could beat it and that was one Brent Linderman built.
Call Brent and ask him how the turbos compair to na on crank issues he will say the exact same thing as Gus and I.
oh and Radski if ya dont mind my restrooms need restocking.

Very funny Product Tester!!! You know my number if you need Some Toilet paper. We will just charge you triple!!!

I really don't care who is right or wrong on this Crank Bearing issue. I have seen many turbo sleds break cranks, and I have seen a ton of Polaris 800 cranks go out. I have seen way to many Boosted and Non Boosted Skidoos break Cranks. Never a BB Cat!!! Just my experience, and doesn't mean I am right or wrong. I think that there is a lot of Variables and conditions that play into a crank breaking or a bearing going out.

I just hope that my sled doesn't break a crank. I have had to pack to many motors in and it just flat stinks!!! Especially in the mountains of Wyoming.

To be honest, I would like to see if all these RKT mods are what they are cracked up to be.

Kelsey, I will be riding the franklin county basin a lot this year, and would like to see how your BB 860 Skidoo runs against my Puny Little Stock Turbo M7. It would be fun to run into you and the North Star Adventure group down there!!!

 

[product tester]

why is it recommended to run a extreem oil like red line in the turboed engines? Just a question???

I run cat APV oil in my sleds

 

[hatchers]

Oh looky here, another thread about turbos and RKT butts in with his misinformation.

NEWS FLASH – RKT does not sell turbos and will do anything in his power to steer you away from turbos kits so he can sell you want ever he had, just give him a call and see what im talking about, dude is nuts…..im not sayin his products are bad, nor am I saying most if not all of his doo drop in kits failed….nope, im not sayin that at all

All im sayin is…id be willing to not drink beer for 5 solid days if RKT would keep his misinformation to himself and stop talking about WTF a turbo sled will or will not do…he got owned last year, to his defense, the sun was in his eyes and lost his lucky racing jacket, so im sure he tends to run better without those two issues…..

Side note - Redline syn is the goodness

 

[hatchers]

why is it recommended to run a extreem oil like red line in the turboed engines? Just a question???

Trust me, I was very skeptical at first, understand I do some lube oil analysis sometimes at work, so I get to read all sorts of BS about different oils....its a science fair that makes me sleepy

One things for sure, my top end looks like new after 1300ish miles/redline syn oil, 112 Sunoco on 12lbs and 12.7ish A/F….im sold on this redline syn oil


and the turbo needs typical engine oil as any other vehicle turbo out there does....some use injection oil becuase the older kits tend to leak a ton of turbo oil into the engine

 

[BIG JOHN]

Nice read...

heres my .02...

ALL engines have "design limits" by the manufacture...

ALL engines are different...if the M1000 Cat crank/rods live with 5psi all day long than that means only 1 thing...the crank train engineer OVER engineered it for its baseline duty cycle...add straight race gas/40-1 premix and 10 psi you have again OVER engineered a couple 2S requirements ALL in the name of reliability...

The combustion time at rpm is the same in a 2S NA/boosted...the 2S has a big hole about 2" from TDC that kinda kills the power stroke...not counting rod angle...LOL..so the LOAD is seen by the crank train...

The 4S has a designated power stroke and the "longer" burn time applies, someone mentioned this, and his data was refering to 4S ONLY.

One still has to see the new stronger rod requirements for the yamaha when bigger boost is added as a factor...Gus 8 psi just getting warmed up in a RX-1...

Moral of my story....more power = more load = more possible failure.-BJ

disclaimer- what the M1000 crank train considers "too much load" is tough to say??...but ADDING 100+ hp to an engine =ing stock duty cycle is a little off base...

 

[hatchers]

wow, this is the first time i disagree with BJ...

"over" engineering is a lose term in my mind....it dont mean much and is generally used amung people with very few teeth

its still a 2 smoke weed eater engine, not an eng. breakthough, very simple design. I cant understand some small engine eng. designs a simple engine to..lets say 5% above normal op. rated temps and loads...this would be silly and the would company fold

on a lighter note, ill be laughing at a 860 all year....oh 60 more CCs eh?....that should make a mega ton of more power!!!!!......hells yes, rock out with your clock out!!!!

Sidenote - i got 1300 miles on a complete stock engine @ 12lbs, 112, redline syn.....plan on topping well over 2K miles

 

[pernikm]

Kelsey is right more thrust means more stress. Correct tune to include timing, fuel delivery and compression ration is key. Incorrect timing with air velocity turn your cylider into a blow torch. Ford svo said a triton v10 would not live at 16psi boost. Yet today i drive one on a daily basis at 26psi. Stock rods collapsed at 750hp. Stock piston failure at 809hp. So stress does happen on rod. That is why a boosted piston is usually designed different than a na piston including ring gap.

Kelsey is right, more hp more stress. But! There are different kinds of stress. Crank shafts twist and crank shafts bend and crank shafts fatigue. Because an engine makes more hp it will make more torque. But torsional stress might not be the failure mode. Cranks cans still bend and they can fatigue. The most interesting thing is that maximum crank bending and maximum torsion will not occurr in phase...meaning at the same rotational location. Clearly NA and turbo engines create different stress at different points in the rotation of the motor.

Another point I want to make is that high hp sleds don't make alot of torque in the grand scheme of things. 150 ft lbs? you can do that with a wrench. I challenge anyone to break a crank end off with a torque wrench. Clearly, cranks are not failing in pure torsion? But take a hammer to a crank and it easy to knock it out of tollerance and the harmonics will smoke it shortly. Take a fat man jumping up and down on a 2X4 he might not break it...but jumping up and down at the right frequency will.

yet another point I want to make is that stresses combine. Throw piece of wire to the bottom of the ocean and nothing will happen. That is because the stress are hydrostatic. Take the wire in bending and it does not take much to bend it. Generally metals fail because of what is called deviatoric stress. That is subract off the hydrostatic stress and you are left with stress that cause distortion. These distortion energy stresses are what cause yielding in materials like steel. Under a combined stress field of bending and torsion there can be areas in the crank that are mostly hystrotic and areas that combine to be distortional. The point being, unless care is taken it is very difficult to visualize stresses that can fail a crank just through thought experiments. I have been doing it for years, and I would not able to expain crank failure without rigorous mathematics. It is that difficult.

So far I have completely ignored fatigue limits that cyclical loading of a crank in bending and torsion would see. I have also completely neglected what diffence in loading larger, heavier pistons might have. I have also completely neglected strain rate information...and to be quite frank, I am not qualified to argue that.

I want to make it clear that I am not chosing sides. NA or turbo might be correct. But realize, so far in this argument, I have not seen the real data nor calculations to declare a real winner.

The only empirical data point we have is that turbos don't seem to damage cranks. At least not at a rate we would expect from a radically modified motor making much much more Hp than the original design intent.

I think the answer is clear. Pay carefully attention. Maintain components well and you will be treated kindly...of course careful engine builders always knew this...

 

[RKT]

Clearly NA and turbo engines create different stress at different points in the rotation of the motor.

This is true.. BUT.. during combustion, where the stresses will be the highest no matter what form they are in.. the engine does not know nor care that how it is aspirated.. Agreed?? The combustion event occurs at the same time, or within a few degrees + or -, no matter how it is aspirated.
AND, IF the combustion produces more work on the crank, then there should be more pressure on the rod and the underlying bearings.. hence.. more stress on the crank at the point of peak cylinder pressure.

So, it stands to reason that the more pressure on the crank train.. the more pressure on the bearings..

I never stated that the bearings were under excessive amounts of stress because of the turbo.. But to claim (like a few did) that the bearings are under LESS stress with a turbo vs. N/A engine would be a stretch.. Wouldn't you agree??

And the whole: bearings being better lubricated because of "blowing oil" ???? Not likely... Wouldn't you agree?

Like More torque stated:

If you have an engine tied to a dyno and just constantly running...

Now 1st set the throttle at 1/2 throttle and run the engine.. Measure the ALL the stresses... This would be representative of the N/A engine

Now take the SAME engine and set the throttle at full throttle and measure all the stresses.. This would be representative of the forced induction.

Which set up would run longer on the dyno before failure??

The turbo is just a means to supply more air.. Nothing more.. The engine does not know nor care how it is fed this F/A charge.. It does not treat ANY F/A charge any different during combustion.. It ALWAYS treats it the same and will combust it accordingly.. The idea that there is some sort of multi timed combustion (like mentioned) is nt very probable.. The engine will combust the same no matter how it is fed its F/A charge. The point of ignition is not altered by the induction method. Agreed?


Great discussion, until people try and make it personal... The tech stuff is much more interesting and we all seem to benefit from it..

Very interested in your thoughts on this Pernikm

Thanks

Kelsey

 

[craveboost]

come on shain, i know last year you lost your crank, i know who fixed it.

 

[BIG JOHN]

wow, this is the first time i disagree with BJ...

BJ-I didn try...LOL

"over" engineering is a lose term in my mind....it dont mean much and is generally used amung people with very few teeth

BJ- its not lose in mine...some motors just make it stock...some can run 10 psi boost...

its still a 2 smoke weed eater engine, not an eng. breakthough, very simple design. I cant understand some small engine eng. designs a simple engine to..lets say 5% above normal op. rated temps and loads...this would be silly and the would company fold

BJ- 12 psi is over 100 hp over stock...5% would be a diff pipe...not sure what your saying here??

on a lighter note, ill be laughing at a 860 all year....oh 60 more CCs eh?....that should make a mega ton of more power!!!!!......hells yes, rock out with your clock out!!!!

BJ- ya might check the RKT/SHR thread...another SHR860R running with/beating 2 PGTM8's..

Sidenote - i got 1300 miles on a complete stock engine @ 12lbs, 112, redline syn.....plan on topping well over 2K miles

good gas + good oil + common sense = happymotor...but dont kid yourself...you have exceeded the design parameters of that engine-BJ

 

[gus bohne]

Re read that thread BJ.
ONLY 1 of those pgtm8's was beaten barely by the 860. the other trumped it but good !!10 feet as I read..
I look forward to our annual new years "Back lake" gathering when the 860's 880's and all the other's get out on the ice.
Not one of them admits to the bore kits, who would when the lil 9 psi 800 rev and the pgf7 are out front .

More misinformation ,,team rkt./shr/...

You 2 just can't get your heads around the love of boost, lack of issue and long life the extra oil foced in by pressure give to us.

Just let it go ladies. We turbo followers are secure in our underwear..LOL

Changing jetting in a manner that inreases power output is detrimental to your health/ the engines health and the economy..ok kelsey ??

Now SHOO !!!! go back to the unboosted side and stay there..

 

[Snowstar]

come on shain, i know last year you lost your crank, i know who fixed it.

First it was a customers crank, the crank didnt fail by itself the center shaft siezed do to lack of lubrication (the lube line fitting was stripped in the case which didnt lube the center shaft) which took out the center gear in the crank.

 

[hatchers]

good gas + good oil + common sense = happymotor...but dont kid yourself...you have exceeded the design parameters of that engine-BJ

yes the stock design was exceeded, that a given

Fun Fact: i got 1300 miles on a complete stock engine pushing 12-14 lbs....and plan on getting well over 2K miles. what if this engine makes it as many many other turbo cat 800s have and will....does this not someone void your point or whatever point you're trying to make? you're starting to sound like errrr Chelsie.....that can't be a good thing

lets all agree a turbo 2 smoke needs a bit more attention, great fuel, and great oil......anyone who does not do this is asking for trouble and should not own one, agreed?

 

[BIG JOHN]

yes the stock design was exceeded, that a given

Fun Fact: i got 1300 miles on a complete stock engine pushing 12-14 lbs....and plan on getting well over 2K miles. what if this engine makes it as many many other turbo cat 800s have and will....does this not someone void your point or whatever point you're trying to make? you're starting to sound like errrr Chelsie.....that can't be a good thing

lets all agree a turbo 2 smoke needs a bit more attention, great fuel, and great oil......anyone who does not do this is asking for trouble and should not own one, agreed?

I completely agree...The fuel/oil you are using is WHY your running strong after 1300+ miles (fuel/timing tune must be solid too)...but for some to say theres NO difference in the life span of bearings/rods/pistons with an INCREASE of HP (BB, NOS,SC,Turbo) are kidding themselves...BJ

 

[BIG JOHN]

Re read that thread BJ.
ONLY 1 of those pgtm8's was beaten barely by the 860. the other trumped it but good !!10 feet as I read..

BJ- I dont have to re-read it...I got it from the Frenchies mouth...10' higher with a turbo vs my NABB...I sleep well at night...

I look forward to our annual new years "Back lake" gathering when the 860's 880's and all the other's get out on the ice.
Not one of them admits to the bore kits, who would when the lil 9 psi 800 rev and the pgf7 are out front .

BJ- Out on the ice is a different story (Back Lake, 500' ele., 3800' of ice)...I would HOPE a boosted sled could MPH a NA sled...BTW are you guys up for the 20 mile trail loop before the race this year??

More misinformation ,,team rkt./shr/...

BJ- What mis-information??

You 2 just can't get your heads around the love of boost, lack of issue and long life the extra oil foced in by pressure give to us.

BJ- I NEVER said I didnt like/want boost( I had one, it was retarded fast)...this thread was asking what "might" happen to a stock motor with boost...I believe I'm more than fair and accurate with my posts...without ANY personal attacks on anyone...

Just let it go ladies. We turbo followers are secure in our underwear..LOL

BJ- Let what go?? Ladies??

Changing jetting in a manner that inreases power output is detrimental to your health/ the engines health and the economy..ok kelsey ??

BJ- Speaking of Kelsey, I hope your joking on his head design...I have TRIED to get a better head for my motors since 2001...havent found 1 yet that can match the efficiency, hp and LACK of DETO..

Now SHOO !!!! go back to the unboosted side and stay there..

Gus...I hope your being funny...I know I didnt say/doo anything to deserve this kinda post...if you have some sort of proof that adding 100 hp to an engine doesnt harm ANY internal parts whatsoever I'm all ears...BJ

 

[Boyko]

Now SHOO !!!! go back to the unboosted side and stay there..

Ha Ha

Gus you crack me up,

I would love to see a big bore on N2O all the time putting out a +100hp over stock with +1000 miles on it.................. Oh I forgot that can't happen because in there word the combustion process happens in the same time as if it stock.

LOL