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Discussion Starter · #1 ·
Anyone upgrade their piston yet?

I threw a 14:1 in my quad and was thinking of upgrading one in the Rhino.

I know what most will say,,,Big bore.. In reading I have seen the motors pick up 4 to 5 HP just on a piston change,,,,but that is in a quad.

Just wondering
 

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Crwcompact said:
Anyone upgrade their piston yet?

I threw a 14:1 in my quad and was thinking of upgrading one in the Rhino.

I know what most will say,,,Big bore.. In reading I have seen the motors pick up 4 to 5 HP just on a piston change,,,,but that is in a quad.

Just wondering
This is something that interest my also. Can anybody enlighten us?
 

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fergie80 said:
Crwcompact said:
Anyone upgrade their piston yet?

I threw a 14:1 in my quad and was thinking of upgrading one in the Rhino.

I know what most will say,,,Big bore.. In reading I have seen the motors pick up 4 to 5 HP just on a piston change,,,,but that is in a quad.

Just wondering
This is something that interest my also. Can anybody enlighten us?
Well, I havent done it......YET, but it's on my list. Ive spent many hours ready on this and here's the conclusion Ive come to...

Big bore 686 is a nice increasein performance and power, but it comes with risk. While I havent heard of lots of issues, there are definatly those that have run into reliability issues. Ive talked to people who've had no issues and love it, and Ive talked to people who've had nothing but issues. Enough to make me scratch it off my list. Reliability is a MUST for me!

High comperssion piston.....Ive yet to run into anybody who's had an issuee with this as long as you stay at 10.75:1. That seems to be the magic number. There are 11:1 pistons out there, and some people swear by them, but Ive read anything over 10.75:1 and your walking the line!

As far as performance, the high compression piston doesnt really get you any more top end, but it does help with low and mid range power, which is waht these Rhino's really need!

Ive also read that an aftermarket cam is a great addition to the piston. There's mixed feelings between the Mudbuster and the Raptor Stage 2 cam, but Im thinking of running the Raptor stage 2.

I'll be swithing to the 10:75:1 piston as soon as I get a few more hours on the Rhino......

Well, those are my personal thoughts and findings.....if anybody out there has actually done any of this, we sure would love to hear about it!! :D
 

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Discussion Starter · #4 ·
Well our problem is weight. We are not dealing with a 350 pound quad. I am a firm believer that you don't have to do a big bore kit to get power.

Of course with any piston change I would get a new cam as well. I am searching for the right combination of piston and cam. Right now it will be a CP piston (hopefully a custom make if I can get it) (by the way, they have a new wrist pin with dimples on it for better oiling).

As far as cams go. WHOOOOOOOOO knows.

Porting the head will be a must.
 

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my 686 big bore w/ ported head and stage 2 cam with dozens of other upgrades is a 12:1 compression, and no problems here! Just a big gas bill from running straight c12 everywhere I go. Like $8 or so a gallon!!! but burns nice and slow, and smells kinda nice! But works great!
 

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Discussion Starter · #6 ·
blahblahblah said:
my 686 big bore w/ ported head and stage 2 cam with dozens of other upgrades is a 12:1 compression, and no problems here! Just a big gas bill from running straight c12 everywhere I go. Like $8 or so a gallon!!! but burns nice and slow, and smells kinda nice! But works great!
I just don't want to run high octane gas. I have to run it in the quad and starting to hate the gas bill for it.

I want to know if anyone has tried a 12:1 piston in a rhino on pump gas. I know you can do it in a quad all day long, but we are talking alot more weight lug around in a rhino.
 

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Crwcompact said:
blahblahblah said:
my 686 big bore w/ ported head and stage 2 cam with dozens of other upgrades is a 12:1 compression, and no problems here! Just a big gas bill from running straight c12 everywhere I go. Like $8 or so a gallon!!! but burns nice and slow, and smells kinda nice! But works great!
I just don't want to run high octane gas. I have to run it in the quad and starting to hate the gas bill for it.

I want to know if anyone has tried a 12:1 piston in a rhino on pump gas. I know you can do it in a quad all day long, but we are talking alot more weight lug around in a rhino.
A 12:1 compression ratio!!?? Wow, id be afraid of blowing the thing through the bottom of the block! :shock: Are you thinking big bore, or just a high compression pistion?
 

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Discussion Starter · #10 ·
blahblahblah said:
blew a head gasket 1st trip out. I run PWR coolers and straight C12 gas now, and its been fine! Runs a lot cooler!
What cam are you running? Stage 2 what,,hot cam?
 

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I Am Running A 730cc With 14:1 Piston For 2 Seasons Now And I Havent Had A Problem Yet. But I Do Have A Carillo Rod In The Motor. But No Blown Headgaskets Here.
 

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may as well convert it to alcohol if you are paying for C12.. get you another 20% power increase and it will run ALOT cooler. and it smells bad ass..lol
 

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What about that stock bore Alba kit? That one catches my eye. They also port the head with that one.
 

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i just bought a 686 10.75:1 but havent put it in.
guy at alba says u need to slow timing, get a bttr fuel pump, cooler plug, and race gas.
-prolly for dune riders running wide open 4 awhile.
i think hes full of sh*t.

does web cams have to use every new valve spring?
kits about as much as the cam.

I've got the Alba kit in the stock bore and they never told me to run race fuel or change the timing or add a fuel pump. It did come with a plug, I never got the fuel pump and I never changed the timing. I've got well over 1000 miles on mine with pump gas. No issues so far. They do recommend race fuel or additives for their 12:1 engine. Any thing over 10.75:1 on pump gas and you are asking for trouble.
 
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