Author |
Message |
The4ork
| Posted on Wednesday, November 11, 2009 - 02:44 am: |
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just looking at the option as i have sourced a set of 9 pistons for dirt cheap, and im getting ready to do a tear down of the motor anyways. i drive around daily usually with about 1/4 tank of 100 octane low-lead and the rest 91. mine is on an older S1 motor, but i figure you guys prably do this mod often, just looking for some insight. of course i cant do computer tuning so im a little bit limited, but i can keep the mixture fat and back the timing off a few degrees if i need to |
Nillaice
| Posted on Wednesday, November 11, 2009 - 04:25 am: |
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i thought the pistons were the same. since 9's crank is a shorter stroke, they have longer connecting rods |
Puddlepirate
| Posted on Wednesday, November 11, 2009 - 06:52 am: |
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Pistons aren't the same. The 9 pistons are domed while the 12 pistons are nearly flat. |
Glitch
| Posted on Wednesday, November 11, 2009 - 06:52 am: |
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i thought the pistons were the same. since 9's crank is a shorter stroke, they have longer connecting rods Nope, and Nope... The pistons are different. 9 pistons in a 12 will raise compression. The con rods are the same size, it's the crank that is different. XB9 pistons in XB12 daily drivable? As far as I've read, yes. |
Hogs
| Posted on Wednesday, November 11, 2009 - 07:14 am: |
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Yes, I believe many have done this and drive them daily, with no worries,I think some have just adjusted their timing abit , but not sure on that, all else being stock like... except the basic mods everyone does... |
Bads1
| Posted on Wednesday, November 11, 2009 - 07:19 am: |
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No unless your running race gas. |
Fast1075
| Posted on Wednesday, November 11, 2009 - 08:18 am: |
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Will XB pistons work with S1 heads??? Aren't S1 heads open chamber....and XB heads bathtub chambers?... (Message edited by fast1075 on November 11, 2009) |
Vagelis46
| Posted on Wednesday, November 11, 2009 - 09:16 am: |
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I use XB9 pistons in my XB12. Firstly I thought it was great with 98-100 octane gas, more power no "pinging". Then one pretty hot day about 25-28Celsius I pushed the bike hard and there was some serious "pinging". After that happened, each time I go for a "fast" ride or to the track I use octane boosters and I am very happy. The bike is flying and no "pinging"... |
Barker
| Posted on Wednesday, November 11, 2009 - 11:41 am: |
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Fuell becomes an issue at 14:1 ish compression ratio. |
Rocketsprink
| Posted on Wednesday, November 11, 2009 - 02:45 pm: |
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Paul James ran his 12 race bike with 9 pistons on pump gas. However, the ecm was reprogrammed which I'm sure stop the "pinging" (Message edited by rocketsprink on November 11, 2009) |
Fast1075
| Posted on Wednesday, November 11, 2009 - 04:04 pm: |
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If I were you, I would call Cycle Rama and ask them if XB pistons will work in an S1 engine....the heads ARE NOT the same on an S1 and XB...For what little I know, the pistons have to match the heads. |
The4ork
| Posted on Wednesday, November 11, 2009 - 09:33 pm: |
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sorry i should have specified... i have nrhs stg3 XB heads and xb12 cylinders |
Hogs
| Posted on Wednesday, November 11, 2009 - 09:40 pm: |
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The4ork, Sorry they won`t Work..But I know someone that will take em off your hands... j/k |
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