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Discussion Starter #1
Well, in my quest of spending all kinds of money I don't have on stuff I don't need, I've been thinking of opening the engine up a little bit. I'm gonna be replacing the tranny parts soon (03 model), and I figure that while I'm in there, I might as well do some performance work. I don't want to get into boring and cylinder liner fitment, but I figured that the easiest way to bump my power up would be to throw a stroker crank in, since the bottom of the engine will already be off. So, I know that I can get a Destroyer crank and CP pistons and everything will work great, but I was wondering how a 1/4" crank would work. Could CP make a set of pistons with the wrist pin offset 1/4"? Will there be any interference with connecting rods on the cylinder bores or crank weights hitting the piston skirts? Basically, I want the biggest displacement increase with the least amount of work, and if I can do a 1/4" crank without having to "make" anything fit, that's what I want to do. I know that the Destroyer crank is a drop-in, but if I can go bigger for no more work, why not?


Thanks for any info.
 

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Color me Gone
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TO put a 1/4 inch crank in you must remove parts of the case for the rods to clear. Usually people grind the case away at the contact points. Often you have to remove the bottom of the piston skirts also to clear the rods.
 

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Discussion Starter #3
So, by remove parts of the case, you mean grab a Dremel and go at it until nothing hits? If so, I have no fear of that :) Also, I could drop in a new crank and pistons without removing the top end, correct? I mean, besides timing the cams, which would probably be replaced at the same time anyway. Anybody know what CP charges for a set of custom-made pistons?

Thanks again
 

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"A" is the only way
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ebrown0104 said:
So, by remove parts of the case, you mean grab a Dremel and go at it until nothing hits? If so, I have no fear of that :) Also, I could drop in a new crank and pistons without removing the top end, correct? I mean, besides timing the cams, which would probably be replaced at the same time anyway. Anybody know what CP charges for a set of custom-made pistons?

Thanks again

I did a group buy last spring from cp, there on the shelf part will be cheaper than a one off, here is the sets that jacqui made on the shelf beside what they already had,


M5075 First choice 12:1, 3.937 (stock bore) for use w/ destroyer crank.

M5077 Second choice 12:1, 4.13 (1250 bore) for use w/ destroyer crank.

M5079 Third choice 12:1, 4.25 (wiseco bore) for 1/4 crank.

M5056 Fourth choice 8.5:1, 3.937 (stock bore) for use with a turbo.

M5078 Fifth choice 12:1, 4.13 (1250 bore) for 1/4 crank.

so as you can tell there is a 1/4 stroke piston setup only thing they would have to do is the make it a 3.93 instead of the 4.13, all these pistons are for stock length rods also.

When I was asking at first, I want to say it was around 600 for a one off set :broke: I'm not sure who is working the harley department now as jacqui has parted ways, but give them a call.

If you can find a s.e. head I would swap the stock heads out for those while you got it apart, taking the heads off will only take 2 seconds since you will have the rest apart.
 

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The Hawk
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ebrown0104 said:
So, by remove parts of the case, you mean grab a Dremel and go at it until nothing hits? If so, I have no fear of that :) Also, I could drop in a new crank and pistons without removing the top end, correct? I mean, besides timing the cams, which would probably be replaced at the same time anyway. Anybody know what CP charges for a set of custom-made pistons?

Thanks again
Pistons won't go in from the bottom, the oil jets are in the way, so you have to remove the heads to change pistons and you would want to anyway so you can measure the deck clearance to make sure the setup is correct.

Mike
 

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Color me Gone
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I'm not aware of any engine that the pistons go in from the bottom, for one thing you need a ring compressor to press the rings and that would be pretty tough from the bottom. As Mike says to replace the pistons you have to pull the heads.
 

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Max said:
I'm not aware of any engine that the pistons go in from the bottom, for one thing you need a ring compressor to press the rings and that would be pretty tough from the bottom. As Mike says to replace the pistons you have to pull the heads.
About the only situation would be an air cooled bike for example. They slide the cylinder down over the pistons after the crank is in the cases.
 

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Discussion Starter #8
Thanks for all the help guys. I've decided that If I do anything, I'm going balls out on a 1430 setup, but more than likely gonna leave it alone (heh, who am I kidding ;) ).
 
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