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12:5 or, 11:1 piston?

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Old 04-21-2004, 07:07 PM
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Default 12:5 or, 11:1 piston?

Is 12:5 piston to much for the starter to be reliable? Or, should i go 11:1 and, not have to worry about starter bearings and, clutches?

What Octane do you run in each compression. If you need more than 110 octane for the 12:5 i will have to go w/ 11:1 JE instead.

How much HP will I be missing out on if i go 11:1 instead of 12:5? Is it worth the starter trouble and, octane requirments?
 
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Old 04-21-2004, 07:19 PM
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Default 12:5 or, 11:1 piston?

idk but my friend has a yfz450 wit a 13:1 n it has alot of hp increase but the start take a lil bit to start it. get a compression release kit (though they sell em fo the kick starrt kit) n u will be fine
 
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Old 04-21-2004, 07:20 PM
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Default 12:5 or, 11:1 piston?

I have a Raptor.
 
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Old 04-21-2004, 08:09 PM
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Default 12:5 or, 11:1 piston?

capt for the 11:1 if it is a tru 11:1 then 91 will be fine, i have tried both and liked the 12:1 better, i picked up about a bike or 2 on the hill drags from going to a 12:1 piston. I used VP red with that piston and she like that the best, it had a octane level of 105...

I would go with a 12:1 cuz you will be that much faster, but if you do you need to be able to feed the carbs that fuel, that's when i sent the stock crabs to Craycraft and they upgraded with a duel fuel line and bigger seats and needles..

the diffrnce is you will spend 40 dollars on gas from a pump on a 3-*day weekend or you can get 3 5 gallon jugs of VP for 90$, I mainley used 2 jugs on a 3 day trip but i took 3 to be safe...

One honest piece of advice i can give you is if you want to be fast and want to beat a majority of people riding go big and do it right, i did it three times cuz i wanted too start small but i have wasted so much money and should have made it a drag raptor from the start, i dident make it fast either cuz i wanted to ride the dune also but now i got 2 quads so i have no problem...
 
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Old 04-22-2004, 10:51 AM
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Default 12:5 or, 11:1 piston?

Do you have starter problems w/ trying to turn over the motor w/ The 12:1 JE pistons? I can Either go 12:5:1 or. 11. I need to decide!

I don't want to be replacing starter every month, week or, day!????

Can i run 100 to 110 octane in the 12:5:1 with out problems like i've seen w/ holes in the pistons?
 
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Old 04-22-2004, 11:19 AM
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Default 12:5 or, 11:1 piston?

Get a Ross piston.
 
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Old 04-22-2004, 12:20 PM
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Default 12:5 or, 11:1 piston?

Don't think i have that option. Motor has been there 3 weeks anyway and, that will prolly add more weeks!
 
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Old 04-22-2004, 02:34 PM
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Default 12:5 or, 11:1 piston?

You need the 11:1 Ross Piston. That is the pump gas piston.
 
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Old 04-22-2004, 03:35 PM
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Default 12:5 or, 11:1 piston?

But will i be going through starters/starter clutches w/ the 12:5:1 and, be searching high and, wide for a million octane?

Or, do you think it is worth the power loss to be safe w/ the 11:1 and, run easy to get fuel and, save my starter?
 
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Old 04-23-2004, 10:21 AM
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Default 12:5 or, 11:1 piston?

Please, need answer ASAP.

How bad is the 12:5:1 on starters? and, Can I run 100-103 octane w/ it?
 


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