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High compression pistons less reliable than stock compression?

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Since it is the off season I'm beginning to think about replacing parts in my bike,piston to be exact.I have heard that the high compression pistons increase power but they're more prone to blowing up.A friend of mine says he won't put any aftermarket part in his engine,he stays true to OEM parts.Is it worth buying a higher compression?Do they last or will they require more maintence because of the increased performance?I don't beat the heck out of my bike either,would that improve the longevity?Finally,my bike is a 2011 RMZ250,bone stock so,would putting in that piston (higher compression) cause me to have to upgrade any other internal parts?

Many thanks-Zach

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I am no mechanic really man, so take what I say with a grain of salt. We are literally doing my top end as I write this. Didn't know what to expect when I pulled the jug off, turns out I still had the STOCK piston (double ring) from 19 mf'ing 98 in the bike and it didn't warrant any real reason for a rebuild, just doing it.

Going with the standard bore wiseco pro lite double ring with all the cometic gaskets and such, but in my mind with anything engine related or performance wise, there is always a give and take...Any time you give more power, there will be a "side effect" if you will, at least in my mind....So, I'd have to say the answer is yes...If you put a high performance piston in and don't beef up other things along with it, then it could def cause some premature damage.

I would call the fellas at wiseco or wherever and ask them...but don't stop there.

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I am no mechanic really man, so take what I say with a grain of salt. We are literally doing my top end as I write this. Didn't know what to expect when I pulled the jug off, turns out I still had the STOCK piston (double ring) from 19 mf'ing 98 in the bike and it didn't warrant any real reason for a rebuild, just doing it.

Going with the standard bore wiseco pro lite double ring with all the cometic gaskets and such, but in my mind with anything engine related or performance wise, there is always a give and take...Any time you give more power, there will be a "side effect" if you will, at least in my mind....So, I'd have to say the answer is yes...If you put a high performance piston in and don't beef up other things along with it, then it could def cause some premature damage.

I would call the fellas at wiseco or wherever and ask them...but don't stop there.

NOTHING could be further from the truth..... Your stock piston is a 12.1 /1 compression where the "HI" compression piston is 13.5 /1..... not enough to know the differance.... You or the engine.... NOW a bigger (280 or 290cc) piston is heaver which pulls and pushes harder on the rod bearing....

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So there is no difference? If there was no difference then it would not exist.

I didn't say there were no differance. I said you or the engine can't tell any differance... 1.4/1 compression is "NOTHING" compaired to 12/1... In another words... Your so called HI compression piston will last just as long as a stock piston with the same rider in the same bike....

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Oh okay! Well that's why I said take my words with a grain of salt! I usually am wrong so whatever I think, I've learned to think the opposite of and that's usually right! :bonk:

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iv had my Crf apart along with many other bikes down to the piston and having to put a whole new top end in it.... ya a high compression piston might give you a little more power but if you want your bike reliable go all stock inside the motor.

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im in the process of rebuilding my bike and im going to use a wisco piston and rings. i think wisco is probbly better than stock and will not be a high compression piston.

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Oh okay! Well that's why I said take my words with a grain of salt! I usually am wrong so whatever I think, I've learned to think the opposite of and that's usually right! :smirk:

dont be so quick to judge yourself as wrong. you are in the right engineering mindset and are following the basic laws of physics (with every action we have an equal and opposite reaction), so it is only logical that an increase in compression will result in a proportional increase in reaction on linked components such as the crankshaft... however, fenderbender is stating that the increase in compression or "pressure" is nearly negligable. especially when your new piston is only increasing the ratio by 0.1 (the stock compression on the 2011 RMZ is 13.4:1)

see:

http://www.suzukicycles.com/Product%20Lines/Cycles/Products/RM-Z250/2011/RMZ250.aspx?category=motocross#Specs

so in other words BlackCR your fine...

Edited by funkinalive

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Oh okay! Wow, thanks for clearing it up man ( I still believe everything I said, but I don't want to present them as factual) as so many do here on the forums...

Edited by BlackCR25098

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