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Has anyone put in high compression pistons? and if so what was the result? please let me know
 

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I put in the 10.5:1 H-D pistons, along with other motor work. Very strong and definitely has more exhaust pressure. Definitely worth it!
 

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10 1/2 to One on the CVO - HD also ~ This was the dealers demo and he stage III'd ~ there are some other tricks to bumpin compression up ~ Head Gasket for starters. I can only tell you that I am at 104/109tq ~ not sure of the stock cvo configuration....
 
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if you put in high compression pistons,the result will be higher compression.this will result in more HP/TQ,this can also result in alot of problems if compression isnt matched to a set of cams.best to have a good build worked up by a good builder.we can put together a couple proven builds together if you want
 

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Has anyone put in high compression pistons? and if so what was the result? please let me know

The intake closing number of your cam(s) will dictate the compression needs for the cam to be the most effective, in any given engine combination.
Feel free to give us a call, and we are happy to discuss this with you.:)
Scott
 

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10 1/2 to One on the CVO - HD also ~ This was the dealers demo and he stage III'd ~ there are some other tricks to bumpin compression up ~ Head Gasket for starters. I can only tell you that I am at 104/109tq ~ not sure of the stock cvo configuration....
Mitchdm,

Typically the stock 110 makes 80-90 hp stock, and 90-100 torque. I would have expected a tiny bit more torque from your build though roughly looking at 115, but might just be a stingy dyno.

2-1-2 exhaust with catalytic converter on the touring
Open air breather
255 cams
 

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A Wood 777 set at 10.4-5, will blow off 115/125 in a 110", as Lone Wolf Perf,tned one with a set of our Stage II CVO Heads/777/Fulsac exhaust combo.
Doc just tuned STGHost's 107"er to just a tick less.
We stay away from the WILD compression, as gas is not getting any better.
Scott
 

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The stage III was done by the dealer before I purchased the Skunk ~ Current Output is 104/109tq. Specs are in my signature. Bike is strong but I'm going to change cams to 777's and having a set of 110 heads reworked for better results.
 

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The stage III was done by the dealer before I purchased the Skunk ~ Current Output is 104/109tq. Specs are in my signature. Bike is strong but I'm going to change cams to 777's and having a set of 110 heads reworked for better results.
Mitch are you running the 255 cams? That thing ought to be close to 120 tq,I suggest getting a good tune..JMO
 

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Is there any benefit to running the high compression pistons with the 255 cams I already have in my bike? I really don't want to do another cam swap.

BTW, my bike makes 87hp and 104tq on the current setup.
 

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Hillside and prodrag are giving you the best advice in my opinion. Just putting pistons in isn't gonna get you the most bang for your buck. Getting components that work well together does. Cams, pistons, heads, intake, exhaust and fuel management all need to work together to utilize each other. When everything works together the results can be more than you thought. Just putting some big cams or high compression pistons alone typically warrant a result...but you'll leave power on the table. In my opinion, an efficient motor runs better. There are a lot of 107's built well that will pull a 117 all day every day because the components work well together. It's hard to believe by most but more common than you think. As far as the 255 cams, that depends on what kind of riding you want to do and where you want your power to be. The 777's are in mine and make great torque from low rpm all the way across the chart. The 255's will be more on the right side of the chart....
 

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Good answer. I ride 2 up 85% of the time and 60% of that is loaded down with gear, so down low grunt is more important to me that upper band hp. I really don't ride much above 3000 rpm's.
 

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I had my 96" bored out to a 103" with 10.5:1 flat top pistons. Nothing fancy, just basic cast aluminum. I added a Woods TW-7H cam and Woods Directional Lifters and it is a great big WOW on the performance. Then I had to go and bolt on Drago's Dragula 2:1 pipes. Now it is a Really WOW on the performance and sound.
 

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Is there any benefit to running the high compression pistons with the 255 cams I already have in my bike? I really don't want to do another cam swap.

BTW, my bike makes 87hp and 104tq on the current setup.
High compression pistons with the 255 SE cam is not a good choice. That cam is designed to build cylinder pressure in order to boost low rpm torque on stock compression motors. With high comp. pistons and that cam you will create cylinder pressure that is beyond the capabilities of any pump gas, so you end up with a ping monster. Compression and cams must be compatible if you want a good performing rideable bike.
 

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Good answer. I ride 2 up 85% of the time and 60% of that is loaded down with gear, so down low grunt is more important to me that upper band hp. I really don't ride much above 3000 rpm's.
FLtroll,

You may want to look at the new Kuryakyn 24d cam build that John Sachs did, use your stock pistons, take the heads off to clean up the exhaust ports on it, maybe shave them just a tad, put on a 58mm throttlebody with decent pipes and you will make near the 120 squared number and have it be reliable and all the torque you have now without the noise of the woods cams or the overall heat of the 255's.

http://harleytechtalk.org/htt/index.php/topic,60244.0.html

Posted another recent 24d build done down in texas and tuned by Ed at the dynodifference





If you are overall happy with the 255's leave it alone, although I think with the upcoming summer heat you may or want a break from the heat there is no overlap in the 255's and they will generate a lot of heat and cylinder pressure.
 

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Is there any benefit to running the high compression pistons with the 255 cams I already have in my bike? I really don't want to do another cam swap.

BTW, my bike makes 87hp and 104tq on the current setup.
255`s & anything higher than 10.0-1 isnt a good idea at all (VERY hard starting,detionation,overheating,ect,ect)
 

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Plus 1 there...... Nice.:D



FLtroll,

You may want to look at the new Kuryakyn 24d cam build that John Sachs did, use your stock pistons, take the heads off to clean up the exhaust ports on it, maybe shave them just a tad, put on a 58mm throttlebody with decent pipes and you will make near the 120 squared number and have it be reliable and all the torque you have now without the noise of the woods cams or the overall heat of the 255's.

http://harleytechtalk.org/htt/index.php/topic,60244.0.html

Posted another recent 24d build done down in texas and tuned by Ed at the dynodifference





If you are overall happy with the 255's leave it alone, although I think with the upcoming summer heat you may or want a break from the heat there is no overlap in the 255's and they will generate a lot of heat and cylinder pressure.
 
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