Author |
Message |
Phelan
| Posted on Wednesday, October 13, 2010 - 04:37 pm: |
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Forged pistons are the way to go if you have the coin. 1250 kit is the easy way to get a good forged piston, new cyls, and clean ring seal with proper break-in. If you get XL heads, make absolutely sure they are from an '04-up XL1200. 883 heads are completely different animals, as are the '03-prior 1200 heads. All of them in stock form are junk compared to '04-up 1200 heads and XB heads. As mentioned, '04-up 1200 heads are identical to XB heads, other than the breather bolt holes are already drilled/tapped. |
Foximus
| Posted on Wednesday, October 13, 2010 - 06:26 pm: |
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I dont have the coin to buy a hole new set of cylinders at the same time... I'm just going to be boring out my current ones. I will buy weisco's if they are good to run in air cooled though, as I love running them in my race engines. How long is a break in period on these ? And yes I understand on the heads. |
Foximus
| Posted on Wednesday, October 13, 2010 - 06:35 pm: |
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http://cgi.ebay.com/ebaymotors/WISECO-PISTON-KIT-1 0-5-1-HARLEY-1200-SPORTSTER-2004-10-_W0QQcmdZViewI temQQhashZitem3f00bd1966QQitemZ270595332454QQptZMo torcyclesQ5fPartsQ5fAccessories#ht_799wt_982 http://cgi.ebay.com/ebaymotors/WISECO-PISTON-KIT-1 0-1-HARLEY-1200-BUELL-1996-2002-_W0QQcmdZViewItemQ QhashZitem5d299c2532QQitemZ400130057522QQptZMotorc yclesQ5fPartsQ5fAccessories#ht_821wt_982 Those seem to be my 2 options by the way... In piston type... not actual purchases. And then maybe this one... not really sure. Could just be a standard sporty piston, that would give lower compression...? http://cgi.ebay.com/ebaymotors/WISECO-PISTON-KIT-E VO-SPORTSTER-1100-1200-10-5-1-010-_W0QQcmdZViewIte mQQhashZitem20b1bd7fc3QQitemZ140420939715QQptZMoto rcyclesQ5fPartsQ5fAccessories#ht_1622wt_1165 (Message edited by Foximus on October 13, 2010) |
Littlebuggles
| Posted on Thursday, October 14, 2010 - 12:25 am: |
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I believe Phelan gave the information I thought Preybird1 would give, thanks! With all I've done to my M2 I'd like to have the engine get some upgrades along this sort... ...wish I'd been following these projects three or four years ago when I had to replace the front head... ...oh well ...someday. |
Phelan
| Posted on Thursday, October 14, 2010 - 06:05 pm: |
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If you get the Wisecos made for Buells, IIRC the *actual* squish on those pistons is 10* rather than the stock 15*. have it measured and cut in the XB heads. Aftermarket cut squish is much more accurate than the factory 15* squish in the T-storm heads anyway. BTW, for the price those Wisecos are what I'd get anyway. |
Foximus
| Posted on Thursday, October 14, 2010 - 07:09 pm: |
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Phelon... that made no sense... I do not have thunderstorm heads, nor will I be getting any. I have standard lightning heads, and might be getting XB heads. So are you saying the new XB pistons have a 10* squish? or just the thunderstorm pistons? |
Phelan
| Posted on Thursday, October 14, 2010 - 08:00 pm: |
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I'm saying the stocked Wiseco 10:5 pistons made for use with thunderstorm heads IIRC actually have a 10* squish instead of the 15* squish the stock T-storm pistons have. Either piston can be used with XB heads if the squish is cut in the head to match the piston. |
Phelan
| Posted on Thursday, October 14, 2010 - 08:04 pm: |
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XB pistons do not have a squish. XB12 pistons have a raised circle in the center of the piston; XB9 pistons have a lump on the piston the shape of the bathtub combustion chamber to keep the compression of the 9 @10:1 even with the same cyls and heads as the 13 but shorter stroke. That's why XB9 pistons in a 12 or tuber with XB heads makes a CR of about 12.1:1 without other modifications. |
Foximus
| Posted on Thursday, October 14, 2010 - 09:17 pm: |
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LoL I feel we are talking in circles. I understand they can be used if the squish is cut in XB heads, but unmodified what does what? If I use my stock pistons with xb heads, what compression does it make? If I use XB12 pistons with XB heads what compression does it make? And if I use XB9 pistons, what compression what does it make? (Answer I guess is 12:1) That being said... is 12:1 to high to run in a 93 octane street motor running lucas straght weight 60 and 2 oil coolers? My goal was/is originally 10-10.5 - 1. Not really sure, though I know I'd like to aim for around 170-180 psi in actually compression readings.... I think... (Message edited by Foximus on October 14, 2010) |
Foximus
| Posted on Thursday, October 14, 2010 - 09:18 pm: |
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Oh, and the opposite... if I run xb 9/12 pistons without running XB heads (so i can install them at a later date...) what happens? I would assume a lower compression.... Also, I dont mean to come off callous, I really appreciate the experience. (Message edited by Foximus on October 14, 2010) |
Brinnutz
| Posted on Thursday, October 14, 2010 - 10:39 pm: |
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XB9 Pistons and XB Heads are about an 11.7:1 compression. I'm running them in my M2 and well, thanks to a couple of awesome buds, she runs like a champ. I'm also running "E" grind cams (same as XB cams, just fit the tuber bushings) with an HD SE selectable ignition. |
Phelan
| Posted on Thursday, October 14, 2010 - 11:01 pm: |
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Neither XB piston will fit with a lightning head because the hemispherical design on the combustion chambers puts the valves too close to the pistons and they will make contact. XB12 pistons with XB heads makes 10:1 compression. Btw, if you haven't recognized it yet, XB9 and XB12 heads are the same monster. XB heads with the stock flat tops will make about 9:1 compression. |
Phelan
| Posted on Thursday, October 14, 2010 - 11:05 pm: |
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I take that back- a 12 piston MAY fit with the lightning head, but I can't verify either way. A 9 piston will not. There is more cc's in the combustion chamber of an XB head than a lightning head so compression would be higher actually than 10:1 with a 12 piston and lightning head, assuming it fits... |
Foximus
| Posted on Friday, October 15, 2010 - 03:23 am: |
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Brinnutz... what is your actual compression? 180psi or so? That is more important to me in building a motor than a "fake" compression ratio. I guess from the sound of it 12:1 isn't all that bad for these motors? |
Brinnutz
| Posted on Friday, October 15, 2010 - 07:40 am: |
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210psi in each. |
Foximus
| Posted on Friday, October 15, 2010 - 11:33 am: |
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Do you know your average head temperatures? Ie... have you laser'ed your head? |
Brinnutz
| Posted on Friday, October 15, 2010 - 11:53 am: |
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Nope. I don't think I really need to worry about it. |
Preybird1
| Posted on Friday, October 15, 2010 - 12:57 pm: |
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Sorry for the late response..I don't check my e-mail. Deffinatly the 04 and up heads. they are the same as phelan stated. Both the heads have the bathtub style, Which harley stole the idea from buell and called them Xl heads. It is easier to use the Xl heads as the Xb are not available (they were on back order when i had my motor built) but you need to have the rear head temp sensor hole drilled and tapped to use the sensor. I traded Dan @ NRHS an un-built Xb head for a fully built Xl head. I believe the Xb head doesn't have the breather holes tapped into them but i am not sure. The Xl heads already have these holes. I just bought the kit From NRHS and had dan custom build this motor for me. |
Phelan
| Posted on Friday, October 15, 2010 - 01:53 pm: |
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Buell paid Harley to build the XB motor parts, and Harley used the same castings for the heads for their rubber duckie 1200 sportsters, modified to suit their needs. Not necessarily stealing, but similar. You're right though, the XB heads do not have the breather bolts drilled and tapped. |
Foximus
| Posted on Friday, October 15, 2010 - 02:13 pm: |
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ok.. so it looks like I'll buy xb9 pistons and XL heads. 210 psi should not need pressure relief valves I do not believe... nor be too hazardous on the starter without them? |
Brinnutz
| Posted on Friday, October 15, 2010 - 02:44 pm: |
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I don't have problems with stock starter. No, you don't need any pressure relief valves, that's crazy talk. |
Foximus
| Posted on Friday, October 15, 2010 - 03:13 pm: |
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Thumbs up. I think I may be all set guys. I appreciate it. Maybe one more thing... it seems XB pistons are just labeled as XB pistons. Anyone have a part number for wiesco xb9's? |
Rick_a
| Posted on Tuesday, October 19, 2010 - 02:26 pm: |
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Keep in mind that in FL near sea level you can't get as crazy with compression ratios as those in higher altitudes. In my own personal experience anything higher than 10.5:1 or so can be problematic. A fully programmable or selectable curve ignition could allow something more aggressive, but lower rpm running could end up soft. A cam with a later intake close could do the same, though then lower rpm running could end up rough. |
Brinnutz
| Posted on Tuesday, October 19, 2010 - 10:00 pm: |
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Rick, is 800ft elevation that high? I run it and that's the elevation I'm at...And it's AWESOME. (Just ask Pyrobee, he rode it today). |
Foximus
| Posted on Tuesday, October 19, 2010 - 10:14 pm: |
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I also have Crane cams... Though I dont know which. I guess I'll figure out when I start to tear apart my motor. 800 feet is barely high at all. |
Pkforbes87
| Posted on Wednesday, October 20, 2010 - 06:03 am: |
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Wilson, 210 psi @ 11.7:1 ? My X1 tested 230 front / 200 rear immediately following a 500 mile break-in on the 10.5:1 pistons. What gaskets did you use? I have Cometic .040" on the head and .020" on the base. BTW, the X1 is down again now because the front head gasket started leaking. Sort of odd that it's the one that leaked only 6000 miles after testing 30 PSI better than the rear. |
Rick_a
| Posted on Sunday, October 24, 2010 - 03:04 am: |
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A high CR is the last place to go for power. For a street bike the small gains in power come with a lot of negatives. That just me and YMMV. |
Foximus
| Posted on Sunday, October 24, 2010 - 11:17 am: |
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Its a jetski thing I guess.... we race with high compression. |