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Discussion Starter · #1 ·
Installed the stroker crank last weekend and I have been chasing my tail all week. I can't seem to get any more performance than before the crank. The low end was better and so was the mid, but I lost some on top.

It acted like a jetting issue and IP2 gave me a dozen things to look for.

After talking with Josh (IP2) about a million times he sent me in the right direction.

He said to work backwards, taking all my mods out of the picture. No matter what I did, it never got better. Well, I went so far backwards I ended up with the motor on the bench last night.

I started tearing it down tonight and got as far as the flywheel and found the problem. Behind the flywheel is totally soaked with gas/oil. The crank seal is wasted. This pretty much explains why I have been having problems.

Just be sure to check your seals, or even better, just replace them while it's tore down. It will be well worth the few minutes to replace them, then to go through what I did this week.marcelo
 

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Have you fired it back up since you replaced the seal?

WFO Racing said:
Installed the stroker crank last weekend and I have been chasing my tail all week. I can't seem to get any more performance than before the crank. The low end was better and so was the mid, but I lost some on top.

It acted like a jetting issue and IP2 gave me a dozen things to look for.

After talking with Josh (IP2) about a million times he sent me in the right direction.

He said to work backwards, taking all my mods out of the picture. No matter what I did, it never got better. Well, I went so far backwards I ended up with the motor on the bench last night.

I started tearing it down tonight and got as far as the flywheel and found the problem. Behind the flywheel is totally soaked with gas/oil. The crank seal is wasted. This pretty much explains why I have been having problems.

Just be sure to check your seals, or even better, just replace them while it's tore down. It will be well worth the few minutes to replace them, then to go through what I did this week.marcelo
 

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Discussion Starter · #4 ·
snowboardgeek1 said:
Have you fired it back up since you replaced the seal?
Gotta find one tomorrow. I have a place down the street called Michigan Ball Bearing that carries about every bearing and seal imaginable. They should have one.
 

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If you would have looked at my thread, when I explained my install, I stated that the key was hitting and binding my seal. I gound mine down. good luck.
 

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Discussion Starter · #6 ·
rabeb25 said:
If you would have looked at my thread, when I explained my install, I stated that the key was hitting and binding my seal. I gound mine down. good luck.
The key was removed prior to installing the crank. That's not was caused it to leak. The other seal is leaking as well. I have a feeling the seals were on the way out and with the increased crank case pressure from the stroker made the leaks noticeable.
 

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WFO Racing said:
The key was removed prior to installing the crank. That's not was caused it to leak. The other seal is leaking as well. I have a feeling the seals were on the way out and with the increased crank case pressure from the stroker made the leaks noticeable.
I'm trying to visualize the seals guys. Are they a gasket in between the two halves of the case? Maybe point me to one of the pics in the HOW TO thread on the crank. Thanks in advance.
 

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WFO Racing said:
Gotta find one tomorrow. I have a place down the street called Michigan Ball Bearing that carries about every bearing and seal imaginable. They should have one.
Hey WFO, are you around the Flint area?? PM me if you are. I'm in Flushing.....we need to get together and RIDE!!!

Banzai !!!!!!!!!
 

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eldevioso said:
I'm trying to visualize the seals guys. Are they a gasket in between the two halves of the case? Maybe point me to one of the pics in the HOW TO thread on the crank. Thanks in advance.
think of a shaft sticking through a hole.

There needs to be a seal so the air/fuel mixture doesn't leak out.


The crank shaft comes out each side of the motor. One side has the clutch on it and the other has the flywheel. Both sides need to be air tight.
 

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Discussion Starter · #12 ·
Got the new seals today and it's back togeather. Did a compression check and it's up from 180lbs to 190lbs with the new seals. I'll be running it tomorrow and see what this thing will really do!
 

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by saying you have 190 lbs of compression, you mean you hooked up a compression check gage to your spark plug hole and yanked on it till it stopped going up?
if so thats a hell of alot of compression! i think mine was only 90 stock.
You got race fuel in that? :)
 

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WFO Racing said:
Yes........ported the exhaust to 31mm wide, raised it 4mm and lowered it 1mm.

The piston should not be indexed.
My BB piston came indexed, so what do I do for that?
 

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Discussion Starter · #17 ·
tblumer said:
My BB piston came indexed, so what do I do for that?
You are screwed there. IP2 and Tyler are aware that this will be a problem. I think Tyler will be getting a bunch of pistons soon.
 

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Discussion Starter · #18 ·
SUX2BU said:
by saying you have 190 lbs of compression, you mean you hooked up a compression check gage to your spark plug hole and yanked on it till it stopped going up?
if so thats a hell of alot of compression! i think mine was only 90 stock.
You got race fuel in that? :)
Actually, it was three pulls at wide open throttle and yes, it is a butt load of compression. My 140hp snowmobile has 145lbs per hole.

I will be running 100 octane race fuel tomorrow and also trying 112 octane if I can get it.
 

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Glad that I held off on tearing the engine apart for now:(


WFO Racing said:
You are screwed there. IP2 and Tyler are aware that this will be a problem. I think Tyler will be getting a bunch of pistons soon.
 
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