Reed Valve Piston?

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Mar 29, 2016
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#1
Ok so done a bunch of sh*t so far to my used bike. But I was rebuilding the top end and I broke a piston ring and the piston looks shitty.

Mz parts is near me and I have a $12 credit for a broken chain.

What is the difference between the standard piston and this one that accepts a reed valve

http://www.ebay.com/itm/272093326371

Its only $10 more and looks interesting.
 


butre

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#2
if you don't have a reed valve that piston won't work for you. if you do have a reed valve, it wasn't doing anything with a stock piston
 




FurryOnTheInside

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#6
No you can't. Well I suppose you could but really you should read up on both to understand what they do, how they do it, why they do it and why you would not want, need, or be able to use both at the same time. Use the search function and just do a bit of reading in the evenings since it's free to read the forums but all these engine parts are not. It will hopefully make your engine a little less mysterious.
 

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#7
No you can't. Well I suppose you could but really you should read up on both to understand what they do, how they do it, why they do it and why you would not want, need, or be able to use both at the same time. Use the search function and just do a bit of reading in the evenings since it's free to read the forums but all these engine parts are not. It will hopefully make your engine a little less mysterious.
Ok well could I just use it for now until i get a reed valve. I just don't want to have to take this engine apart again if I want to upgrade.
 

Frankfort MB's

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#8
If you put a reed valve on your bike I would recommend getting the piston, but if not it's no good for you
A boost bottle does nothing for any HT engine
 



jaguar

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#11

Frankenstein

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#12
the boost bottle was designed by Yamaha to prevent the pre-powerband power dip that happens with reed valve and expansion chamber.
But it's highly specific as to sizing and length etc. You can't just buy one and stick it on. That will do next to nothing.
Read up on boost bottles at http://www.dragonfly75.com/motorbike/YEIS.html
and reed valves at http://www.dragonfly75.com/motorbike/reedvalve.html
If anything could intellectually prove that every single last penny spent on a boost bottle was a complete and total waste of time and money (and what should be trust of certain vendors) then this would be it. It would be like selling a haircut that could promise to make anyone and everyone who adorned it irresistible to the opposite sex. It can work in some cases but the majority absolutely not. You need to find the right accessory for the subject it's fitting, one size fits all is mostly untrue.

This is why I don't buy performance parts for a jaguar and stick them in my ford, even if I can make it fit it doesn't mean my truck magically turned into a foreign sports car or will even operate like one, in fact it will probably be worse than stock. Putting an ill fitting boost bottle doesn't turn your bike into a Yamaha that could cut you in half with its back wheel. It does make you an idiot however if you finished reading this and still think that the run of the mill motorized bike boost bottle isn't a cleverly designed form of rape.
 

jaguar

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#13
agreed.
But I designed a boost bottle for my Suzuki 100 and it does exactly what Yamaha said it would do. I wouldn't be without it. On the street you don't want power dips anywhere in the powerband.
I made a boost bottle calculator to help anyone get the design just right. But you have to know at what RPM the power dip is happening before you get the power boost from the expansion chamber. You can do that with a speedometer and some calculations.
 

Frankenstein

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#14
agreed.
But I designed a boost bottle for my Suzuki 100 and it does exactly what Yamaha said it would do. I wouldn't be without it. On the street you don't want power dips anywhere in the powerband.
I made a boost bottle calculator to help anyone get the design just right. But you have to know at what RPM the power dip is happening before you get the power boost from the expansion chamber. You can do that with a speedometer and some calculations.
What's with the but? The point was that you actually had to design it, there's currently no other option. For most people who can't repetitiously tune a motor to the same way let alone maintain a specific setting this is probably way too much for them, the entire idea is that you have to keep the motor precisely the same to keep the boost bottle in tune. As soon as you "upgrade" a part you can be out of tune that easily. Reality is that only after purchasing and breaking in every last upgrade you want can you start working on the concept of an appropriate boost bottle, once you know the maths then you can move on you actually bringing it to life and installing it. Any time before that and you are chasing insanity up a tree.
 


Frankenstein

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#16
exactly
The "but" was for those that think boost bottles are completely useless.
Yeah I should probably explain my hatred only extends to the version marketed to motorized bike users, it is a sound idea but in this case completely inappropriately designed, by all practical reasoning it isn't a boost bottle unless it can actually physically create a 'boost' where it's needed. Currently no commercial boost bottle (by real life definitions) exists for the China girl at this time..
 


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