big bore opinions

I've been thinking for a while about a big bore kit for the rhino ,want to keep it reliable and don't want to be to extreme so i'm staying away with the stroker, but am alittle scared about the stock middle gear problems , what size do you guys run and what are your thoughts mick

I have a stroker... the most common for the 660 though is the 686 kit... little power is gunna come from the bore size though. Your head and cam is what makes the magic happen

I wonder if we can get a multiple rhino discount......lol

may want to think about the hours you have on moter , new oil pump, an the middle support would be must do for bottom end if nothing else was done in the bottom . as for bore 686 I think is good but I also think 4mm stroker can be reliable also x2 on the porting of head & cam just don't forget the correct springs for cam........ the old saying no replacement for displacement

the "power" that everyone wishes they had more of is a deceptive critter...

increasing the bore size will help increase the displacement and the horsepower, and put "power" in the higher rpm
increasing the stroke length will help increase displacement and the torque, and put "power" in the lower rpm

stock rhino engines are relatively short stroke, "oversquare" engines, designed like motorcycle engines to save space in the mounting location.
what James has done with the cvt in the rhino helps bridge the gap of that short stroke motor to "dig" and wind out better.

porting the head will help either motor, but once you head down either path (torque or horsepower) with porting it's expensive to change (you have to re-do everything).

so it all depends (!) on whether you want a "torque motor" or a "horsepower motor."

your vmax is probably a "horsepower motor", and my harley is a "torque motor."

my driving style and the environment in which i ride (tight trails & mud) put me in the "torque motor" category.
if you run flat out on open trails & streets, you would want a "horsepower motor."

just my 2¢

there's a really good explanation of "square" at http://en.wikipedia.org/wiki/Stroke_ratio

actually my v max is both I could roll on in 3rd an start burnin the rear tire but know what you mean and if I have to address the middle gear and split the case might as well do a stroker, maybe james will chime in, my motor is low hours under 150 yes I know that's real low for an 07 sometimes I get real busy at home and work

yea i'm thinking like you like speed but leaning towards more torque for hills and mud, thanks

You don't have to build only a stroker or only a HP motor. I went with a +6 bore and a +6 stroke and ported the head with over sized valves for all around power everywhere. So far my machine has been very reliable also. I know I surprise all the RZR's when they run into me for the first time. They are used to walking away from Rhino's. My Rhino is a 780, when you need that low end grunt it's there with lot's to spare. The top end is there as well, I have hit mid 60's with 4 people in it totaling more than 700lbs.

i love a stroker...its more money but more power

Well worth the money in my opinion.

rich guys...lol...you gotta pay to play:[URL=http://ww

how big can I go with the 660 and still remain reliable on pump gas

brewis wrote:

I wonder if we can get a multiple rhino discount......lol

For the Hotrod boys I will do $290 shipped. Tax in CA. Alba Racing 686cc kit

http://www.teamalbaracing.com/product.php?productid=2423&cat=363&page=1

This is the kit we run in the SCORE Champion Yamaha Rhino 660. Doesn't get more proven than that... for that price you will receive:

Yamaha bored and honed cylinder to 102mm
CP M1016A Forged 11.0:1 piston, rings, pin, and clips
Cometic C7798 Top-end Gasket kit.

If you would like to run pump gas without concerns we do offer a 10.0:1 CP as well. It is a custom piston and runs $15 dollars additional...

You will have to call the shop to get this price and use code word "HOTROD IS THE MAN!" and we will get you going. We do need your old cylinder as a core, so no cracked skirts or damaged cylinders please. If you do not have a core or don't want to send yours in there is a $150 core fee.

Nate
Alba Racing

mine is a +4 crank an +2 bore   not have a lot of time on it yet but I think it will be  reliable

great price!!!..thanks Nate!!!

ALBANATE wrote:

brewis wrote:

I wonder if we can get a multiple rhino discount......lol

For the Hotrod boys I will do $290 shipped. Tax in CA. Alba Racing 686cc kit

http://www.teamalbaracing.com/product.php?productid=2423&cat=363&page=1

This is the kit we run in the SCORE Champion Yamaha Rhino 660. Doesn't get more proven than that... for that price you will receive:

Yamaha bored and honed cylinder to 102mm
CP M1016A Forged 11.0:1 piston, rings, pin, and clips
Cometic C7798 Top-end Gasket kit.

If you would like to run pump gas without concerns we do offer a 10.0:1 CP as well. It is a custom piston and runs $15 dollars additional...

You will have to call the shop to get this price and use code word "HOTROD IS THE MAN!" and we will get you going. We do need your old cylinder as a core, so no cracked skirts or damaged cylinders please. If you do not have a core or don't want to send yours in there is a $150 core fee.

Nate
Alba Racing

This is awesome .... thanks so much to Nate & all the guys at Alba!!!!

my +5 had 3000 + miles and was still going...my last one +6 lasted 2000 and only failed because my heater core got a leak and i didnt know it and overheated bad while i was waiting for it to warm up good cause it was cold that day...

ALBANATE wrote:

brewis wrote:

I wonder if we can get a multiple rhino discount......lol

For the Hotrod boys I will do $290 shipped. Tax in CA. Alba Racing 686cc kit

http://www.teamalbaracing.com/product.php?productid=2423&cat=363&page=1

This is the kit we run in the SCORE Champion Yamaha Rhino 660. Doesn't get more proven than that... for that price you will receive:

Yamaha bored and honed cylinder to 102mm
CP M1016A Forged 11.0:1 piston, rings, pin, and clips
Cometic C7798 Top-end Gasket kit.

If you would like to run pump gas without concerns we do offer a 10.0:1 CP as well. It is a custom piston and runs $15 dollars additional...

You will have to call the shop to get this price and use code word "HOTROD IS THE MAN!" and we will get you going. We do need your old cylinder as a core, so no cracked skirts or damaged cylinders please. If you do not have a core or don't want to send yours in there is a $150 core fee.

Nate
Alba Racing

Nate,
Is this kit ALL i would need to do the 686 conversion?  or do i need a new fuel pump and carb and some other stuff?  Im really thinking this is a great way to go for me.  About what kind of HP gains would we expect to see from the 686 conversion? And this is a GREAT price!

thats all you will need...unless you want MORE HP!!!...lol

LOL...i always want more...but if thats all i need to START getting more then i can add later then im good with that.

Vital wrote:

You don't have to build only a stroker or only a HP motor.

no, but when you are planning a build you should keep the difference in mind. the earlier you can achieve peak torque, the better the engine will feel in everyday driving.

I run 87 ethanol free gas unless I miscalculate on how much to bring with us. When y'all say "runs on pump gas". Are you saying 87 or 91, ethanol free 87 or 91. If the build requires higher octane and it happens to not be available is it possible to add a octane booster like 104+ or similar to you what you have available?

At what point in a build do you know the stock radiator is not enough and you need a aftermarket radiator or larger fan or both?

Madmax 1 wrote:

how big can I go with the 660 and still remain reliable on pump gas

I have been on my 660/780 for over 3 years. My buddy has been on his 660/800 for over 4 years. As long as you keep the oil changed and don't drown them they are very, very reliable if they are built right. Running pump gas or high octane fuel only depends on your compression ratio, I.E. your piston. Keep the piston to 10/1 or so and you're fine running pump gas. I think even 11/1 will be ok with 91-93 octane. Some people like to deck the head for more compression as well but I like the ability to run pump gas more than another HP or two. YMMV.

what kind of HP gains will i see out of the 680 kit?

That 780 kit sounds AWESOME!!!! but i wonder how much drive-ability i would loose? As far as putting around slow speed like my son and daughter do.

Vital wrote:

Madmax 1 wrote:

how big can I go with the 660 and still remain reliable on pump gas

I have been on my 660/780 for over 3 years. My buddy has been on his 660/800 for over 4 years. As long as you keep the oil changed and don't drown them they are very, very reliable if they are built right. Running pump gas or high octane fuel only depends on your compression ratio, I.E. your piston. Keep the piston to 10/1 or so and you're fine running pump gas. I think even 11/1 will be ok with 91-93 octane. Some people like to deck the head for more compression as well but I like the ability to run pump gas more than another HP or two. YMMV.

what did your motor cost you , what is your speed