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Buell Forum » Knowledge Vault (tech, parts, apparel, & accessories topics) » Engine » Big Mechanicals: Head, Cyl, Piston, Rod, Crank, Flywheel, Cases, Bearings » Archive through July 16, 2008 » XB12 Piston Info Wanted « Previous Next »

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Ilikeike
Posted on Saturday, September 29, 2007 - 02:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Good Morning,

First poster here hoping to gain from the collective wisdom of all you Buell wizards.

I ride a Sportster and can no longer resist the temptation of XB12 heads. So, that will be this winter's project.

I'm trying to decide on pistons. I really like the look of the OEM XB12 pistons but that's not much of a criteria.

What do YOU think of them? You're the people that are actually using them. Are you happy with them or do you plan on putting something else in at the first opportunity?

Does anyone have a weight on this piston? I'd like a stripped weight as well as a weight with rings and wrist pin.

Does anyone have the OEM part number?

Thanks for your time,
Walt
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De50man
Posted on Saturday, September 29, 2007 - 04:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't have my manual on hand for the part number.

I know of a person running a turbocharged XB with everything internally stock besides the gaskets(EricZ). He is pushing 135 HP and 110 ft/tq at the rear wheel, and has not had any problems that I know of with his pistons.

I can't help you with the weight off hand, but I'll see if I can scrounge some numbers up.
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Ilikeike
Posted on Saturday, September 29, 2007 - 06:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thanks De50.

A few more particulars. I'm not doing a high horsepower build. At least by your standards. If I get 75 or 80 I'll be more than happy. I probably won't even check it.

I'm more concerned with things like longevity and vibration. Hence the curiosity about the weight. I'd like to have an idea of the 'sweet spot' rpm. I'd like to get another 30,000 smoke free, trouble free miles. And, sneak in a dozen or so trips down the quarter mile.

If I'm not mistaken, it's a cast rather than forged piston. How snugly can it be fitted to the cylinder? Being cast really appeals to me. I've seen a few folks get the forged ones a bit loose and it sounds like a rattle can. I don't know how they live with it.

Didn't they also go to a low friction 1 mm top & middle ring?

On a similar note, it appears that Zippers no longer offers the light weight tool steel wrist pin. Does anyone know of any other company that's making them?

Thanks again,
Walt
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Alessio66xb12r
Posted on Saturday, September 29, 2007 - 07:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt i think your sportster is a 1200 of course so...
xb heads are stock on 2004 and up sportster 1200 models , the point is you have a different flywheel (LIGHTER)...so forget about xb performance whith an heads changing.
if you want to have more power in your bike
without loosing longevity and most important without vibrations every change in pistons assembly need crank to be balanced....
i did a sportster cafe' racer few months ago , i got a very nice power delivery with:
flowing my 883 heads bigger valves in.1.710
ex.1.515 , STOCK CAMS , wiseco forged 1200 pistons ,1200 cyl. , 9.5 C.R. , dynojet kit on stock carb. , and open home made air filter, performance exhaust,
you can see the bike on K.V. in " do it yourself" ,"opinion needed" thread.
i did not balanced the crank for the new pistons assembly so....VIBRATIONS.
on pistons for me the best you can do :forged C.P. or forged WISECO

the best you can do also ....
waiting for Pammy reply or others more expert than me
bye Alessio
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Alessio66xb12r
Posted on Saturday, September 29, 2007 - 07:44 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

sorry
wrong
"you have a different flywheel lighter..."
right
"you have a different flywheel HEAVIER"
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Puddlepirate
Posted on Saturday, September 29, 2007 - 09:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I've got the new style heads with stock CR (9.7:1) pistons and .551 cams and I'm up to 80hp on my 2001 (former) 883 Hugger.

I got my heads on ebay for a little over $300, and I got brand new takeoff 1200 cylinders and pistons, along with a set of .551 Screamin Eagle "E" cams for $250 total.

22650-04A is the p/n for the 2004+ XL 1200 pistons, again with a 9.7:1 compression ratio. Run a .030 base gasket and you're right around 10:1 CR. You can also pick up higher compression pistons from Harley for about $225, or on ebay for much cheaper. If you get into the 10.5:1 CR range, you should be able to get at least 85hp with supporting components. I don't have the number for the XB12 pistons.

Run the new heads and pistons with a set of mild cams and you should be able to gain AT LEAST 15hp.

If you haven't looked yet, check out the XL forum, www.xlforum .net . There is a wealth of information on the subject.
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Alessio66xb12r
Posted on Sunday, September 30, 2007 - 04:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

to Puddlepirate
did you balanced the crank to ?
there is a lot of difference in weight between 883 pistons assembly and a 1200
for me this is the most important step to do.....and is not so cheap.
bye Alessio
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Puddlepirate
Posted on Sunday, September 30, 2007 - 09:12 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

No Alessio, when going between 883 and 1200 in a Sportster there is no need to balance the crank. The 883 and 1200 crank/flywheels are exactly the same, after 1995. Here is some info taken from www.nhrsperformance.com

"I got asked about this today and I did a little research and thought I'd pass along the findings.

Piston weights, according to my gram scale:

stock 883: 332g
Hurricane 1212 10:1 dished conversion: 391g
Wiseco 1200 dished conversion: 391g
stock 1200 flat top: 484g

All weights are with pin, but without rings or clips.

Wiseco offers 3 different conversion pistons with 3 different compression ratios and I'm not sure which one this is, it's a used piston I had sitting around.

But if you're worried about throwing the motor out of balance by doing the conversion, here's some food for thought. I spent some time looking through old parts books, trying to figure out if HD actually balanced the 883's and 1200's differently. Well, according to the part numbers, they did use a different flywheel assembly for 883's versus 1200's up through 1994. But from 1995 until at least 2004 (I don't have parts books for '05 and '06), the 883 and 1200 use the exact same flywheel assembly.

883:
88-89: 23905-88
90-00: 23905-89
01-03: 23905-00
04: 23905-04

1200:
88-90: 23900-88
91-94: 23900-90
95-99: 23905-89
01-03: 23905-00
04: 23905-04

So the 1200 started getting the 883 flywheel assembly in 1995. Also, if you go to order an 88-94 1200 assembly now, it supercedes to the 883's 23905 part number.

FWIW, I also weighed various other XL pistons I have sitting around:

stock 1200 flat top: 484g
KB 1200 flat top: 442g
Hurricane 1212 flat top: 412g

stock Thunderstorm: 500g
Hurricane 1212 Thunderstorm: 434g

Wiseco 1250 Thunderstorm: 473g
Hurricane 1250 Thunderstorm: 447g"

If doing a 88" or a 90" to my engine I would definitely balance the crank. It is just not necessary to do it to a 883/1200/1250.
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Alessio66xb12r
Posted on Sunday, September 30, 2007 - 10:11 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

its the same was told to me when i converted my sportster to 1200 with flat top wisecos "no crank balance needed" ...
and i did not ....(BIG VIBRATIONS) ..but what i really can't understand its how this is possible with a so noticeable difference in weight.
i read also something about this in the sportster tech page " tom's metty conversion"(i think he was...) when he was working around flywheel assembly he noted that his 883 crank was a 1200 crank with a different position of "balance holes".
so maybe 883 and 1200 use the same crank with a different balance.
now i'm building an 88 on my xb , the crank will be the same as stock but with a lot (5 on the left and 7 on the right) of holes to balance the new different weigh of pistons assembly.
i repeat ...i cant understand how a so different weight in pistons assembly can be balanced by the same crank.
i did not say that i'm right ..
maybe there is some mathematics stuff that i don't know ....YET.
nice to speak with you
bye Alessio
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Ilikeike
Posted on Sunday, September 30, 2007 - 11:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Allessio

so forget about xb performance whith an heads changing

I have no delusions about xb performance. My hopes lean more toward a stock 04 Sportster.

Puddlepirate

$550.00, that must be a record for 'bang for the buck'. Good show. Not the build I'm looking for but it impresses the Scots in me. 22650-04A comes up snake eyes on both Chicago HD and Zanotti's, are you sure you got it right?

info taken from www.nhrsperformance.com

There seems to be a bit of controversy as to the accuracy of that information. Check out this page from HQ: http://www.head-quarters.com/html/piston_specs.htm l

and this thread at XLForum (yes I'm familiar with the site): http://xlforum/vbportal/forums/showthread.php?t=43 879
Note: I could not get a link to XLForum to work properly. You'll have to paste into the address bar and remove the space in the thread number.

Post #6 by addertooth I believe to be particularly accurate and informative and it agrees with HQ. But, none of them address the weight of the late model pistons from Harley or Buell.

Post #8 points to the info that you were so kind as to look up. It seems to be required to accept this as fact in the face of conflicting evidence.

Post #8: I'd love to find titainium wrist pins. Anyone have brand and part number?

Post #10: adder checks his figures and attempts to sooth the faithful.

Post #12: The faithful are having none of it. That's one of the reasons I'm posting here. They seem a bit unwilling to question the accepted wisdom. I'm hoping Buell riders will be of a more engineering bent.

Post #13: That's it in a nutshell. Not mentioned anywhere is that lighter pistons (like a lighter crankshaft) will let the motor spool up faster. This is why racers are always on the lookout for lighter reciprocating bits.

Post #16: The Zippers wrist pin for the Sportster appears to have been long gone. More accepted wisdom that is obsolete.

Post #17: I find this post particularly enticing and the reason I'm looking into OEM pistons. In the past, OEM slugs were just that - heavy slugs. It appears things may have changed. "Inquiring minds want to know."

I did make one inquiry over at XLForum. It landed with a very silent thud. Care to have a go at it? http://xlforum/vbportal/forums/showthread.php?t=82 923

Thanks for reading my drivel,
Walt
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Ilikeike
Posted on Sunday, September 30, 2007 - 11:53 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Allesio,

Yup, a lot of people get BIG VIBRATIONS.

Most of them just blow it off because they are so happy with the new found power. I think it would get old quick.

I'm trying to simply skirt the issue entirely by finding just the right piston.

Gear up, flaps up,
Walt
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Puddlepirate
Posted on Sunday, September 30, 2007 - 02:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't know why the part number doesn't come up for those pistons. It is correct though. I've got pics of my pistons before I installed them, and they are both marked with that number. I could email you the pic if you'd like, since I can't figure out how to post pics here.

Vibrations under about 2,250rpm are a bit more noticeable, but after that it smooths out nicely. I never have it below 2,500rpm anyway, so I'm not too worried about it.

The pistons listed on the Headquarter website are for the pre-2004 XLs. I honestly don't know the weight differences between the pre-04 and post-04 pistons.

I do still have my 2001 883 pistons sitting in a box at work. I could measure them for you this week if you'd like. I'm getting a bit of headwork done this winter, and I'll make it a point to measure the stock 04+ 1200 pistons/pins/rings when the motor is apart again. I'll be parking the bike in mid-november-ish and rip it apart soon after.

I agree that there is a noticeable difference in the weight of the 883/1200 pistons. I can't explain why Harley uses the same crank for both bikes. Maybe they don't believe that the larger amount of mass is going to do any damage to the engine? I don't have the answer to that.

I do agree that the engine will spin faster and more efficiently with lighter weight pistons/pins/flywheels/rods/etc, as well as having the crank balanced. I personally did not feel it to be necessary on my basic 1200 conversion, since I don't plan on doing anything but casual street riding. If you're just planning on bringing yours up to a stock 1200, I don't see why piston weights would be so very critical. As long as you are at or below the weight of a stock 1200 piston, you should be fine. The lighter the better, yes.

Cost/benefit ratio of disassembling the engine, removing the crank assembly, sending it out and paying a couple hundred for balancing, and then reassembling everything just did not do it for me. There are plenty of people that have very high mileage 883/1200 conversions as well as stock 1200s, so balancing the crank after new pistons seems like overkill for a non-racebike.

I'm also interested to know XB12 piston weights. I asked about it on the xlforum and all I got back was that they would be heavier than standard XL1200 pistons because of the small dome to raise compression. I can't comment on that because I haven't even seen a picture of one.

Good luck finding out. I'll be watching this thread closely.
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Alessio66xb12r
Posted on Sunday, September 30, 2007 - 05:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Puddlepiratei'm sorry i cant help you because i sold xb pistons and cyl. few days ago on ebay. i did not weight the pistons but i remember the small dome and if the only difference in weight from xl pistons is that dome i think is not more than 5 or 7 grams that dome is like a Thin coin in the middle of the top side.
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Alessio66xb12r
Posted on Sunday, September 30, 2007 - 05:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

to Puddlepirate
this is the top side of a damaged xb piston , you can see the small dome
bye Alessio

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Ilikeike
Posted on Sunday, September 30, 2007 - 05:45 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

not more than 5 or 7 grams

That's a real close guess. I did a calc on the volume a while ago and it was right around 2 cc's. Aluminum is 2.7 grams per cc. so that would make it right at 5.4 grams. Not very significant.

And, that assumes that the Buell piston is exactly like the Sportster flat top except for the bump. I'm not convinced, show me.

To assume is to blunder,
Walt
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Ilikeike
Posted on Sunday, September 30, 2007 - 05:48 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

How about asking your eBay buyer if he has a gram scale?

Walt
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Puddlepirate
Posted on Tuesday, October 02, 2007 - 05:46 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt, I measured my 883 pistons today and got these figures:

Piston/Rings/Circlips are 312grams.

883 Wrist Pin is 92grams.

Total Weight: 404grams.

Still looking around to find out how much the stock new style 1200 and XB12 pistons weigh, but I don't have any leads.

Rich

(Message edited by puddlepirate on October 02, 2007)
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Ilikeike
Posted on Tuesday, October 02, 2007 - 07:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Rich,

That is almost exactly the weight given on the HQ website. I'd still like to know if the 883's changed in 2004.

Thanks for the info,
Walt
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Bad_karma
Posted on Tuesday, October 02, 2007 - 11:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walter
I would check with NRHS. But for the money your willing to spend. You should look at a 1250, Stage 1 head work, upgrade in cams, free flowing intake and exhaust. I believe that should reach the goals you out lined with a nice performance upgrade. Also check with zippers. Information is the ticket to getting what you want. By the way I just put an 88" in my S3 and the motor is more powerful than stock, smoother only real question is longevity?
Joe
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Puddlepirate
Posted on Monday, October 08, 2007 - 09:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt, I was finally able to find the XB12 piston/ring assembly part number.

According to the 2005 XB12S parts book, it is 22204-04, which dosn't come up in the Surdyke or Zanotti parts finder. According to the local dealer, the price is $68.25. Unfortunately we still don't know the weight of it. 10:1 CR.

The XB9 piston/ring assy (22707-02) comes up as being $101.60. 12:1 CR in a XL or XB12.

For a little bit more money and compression, the 22711-04 Screamin Eagle XL1200 Forged Piston Kit might do ya. 10.5:1 CR with the stock XB style heads, $228.91 through Surdyke. No idea of the weight on this either, but forged pistons are supposed to be something like 50grams lighter than their cast counterparts.

I don't know if this is a viable option, and I've never heard of anyone doing it to a street motorcycle, but what about removing a certain amount of weight from your piston assembly? I know guys who have done it in very small amounts to get their pistons the exact same weight, so I don't see why you couldn't use it to lighten both a larger amount (without getting too excessive).
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Ilikeike
Posted on Monday, October 08, 2007 - 11:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Hi Rich,

Regarding the 22204-04 number. It's actually 22244-04 which is why it wouldn't come up at Zanotti's for you. I had actually found that number a while back from an ebay auction but when I typed it into Zanotti their description made it sound like just piston rings. Oops, my bad.

I plan to use W grind cams so the 10:1 CR pushes them right to their limit. They are pretty happy at 9.7:1. These cams are one of the big reasons I've been so interested in these pistons, they're made to work as a package with these heads. If the 10:1 proves a bit much, I can just cut off the bump and have flat tops. Problem solved.

For the price from Zanotti's ($50.77), I'm just going to just go ahead and get a pair. Can't go too far wrong.

Removing a little weight if I find them too heavy is exactly the line of thinking I've been pursuing. ("great minds think alike") I own a tool & die shop so the actual cutting is simple enough. I also help a bud with his vintage racer. We use lightened Aires pistons. I'll just copy what they have done.

I'm also hoping to shave a bit of weight with tool steel wrist pins but finding super light ones doesn't seem to be an option any more. I've heard rumors of failures from flexing so I think they have dropped them. JE makes the lightest one I've found but I've not located a vendor yet. Any suggestions??

Speaking of vendors, so far Zanotti's has the entire package. Here is the list if anyone cares to offer advise or comments.

Piston and rings 22244-04 2 $50.77 $101.54
Complete gasket set 0934-0735 1 $101.52 $101.52
Front Head 16872-02 1 $225.97 $225.97
Rear Head 16875-02 1 $225.97 $225.97
Valve Collar Keeper 18260-02 8 $0.22 $1.76
Valve Seal Kit 18094-02A 1 $8.98 $8.98
Valve Spring Collar 18258-02 4 $1.02 $4.08
Valve Spring 18245-02 4 $3.30 $13.20
Feuling Tappets 0929-0005 1 $99.48 $99.48
Exhaust Valve 0926-0202 2 $17.88 $35.76
Intake Valve 0926-0201 2 $17.88 $35.76

$854.02




Regards,
Walt
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Bombardier
Posted on Monday, October 08, 2007 - 10:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

5 grams is a hell of a lot of weight at the speed that pistons reach.
Force= mass times accelleration.

I would balance a motor even if I was changing from one standard piston to another just to be sure.

Cheap insurance.
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Puddlepirate
Posted on Wednesday, October 10, 2007 - 07:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt, one of the guys on the XL forum is selling his stock 1200 top end. You may be able to haggle and get a decent deal on whatever you need...

http://xlforum/pp_classified/showproduct.php?produ ct=2556&sort=1&cat=4&page=1
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Ilikeike
Posted on Wednesday, October 10, 2007 - 08:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Your link didn't work for me but I think I know the ad you're referring to. I considered it and may look at it some more.

Thanks for the heads up,
Walt
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Puddlepirate
Posted on Thursday, October 11, 2007 - 06:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'll keep an eye out for ya...
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Puddlepirate
Posted on Thursday, October 11, 2007 - 09:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt, I found a little more information that you'll be interested in.

The stock piston/rings/pin assembly for the '04+ XL 1200 is 467 grams.

Stock 1200 piston pin is 93.5 grams.

Wiseco 1200 piston pin is 87.9 grams.

The afforementioned Zippers tool steel piston pin's weight is 68 grams, but I can't find it on their website.

I'm also interested to see what your method for removing weight from the piston and pin would be. I've got a couple of ideas in mind, but I'm interested to see what you're thinking.

Regards,
Rich
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Ilikeike
Posted on Thursday, October 11, 2007 - 10:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"The stock piston/rings/pin assembly for the '04+ XL 1200 is 467 grams.

I'm hoping the XB12 piston will be lighter but I'm prepared for the worst.

Stock 1200 piston pin is 93.5 grams.

Yikes, that's even worse than the 92 grams that has been quoted for earlier years.

Wiseco 1200 piston pin is 87.9 grams.

That sounds very similar to the JE pin which is what I intended to start with. JE provides some very good engineering data for their stuff. The JE pistons is 52100 steel. This is a common and excellent bearing steel. I expect it's hardened to the Rc 65-68 range. Unfortunately, I emailed JE and got zero response. As soon as I get caught up a bit, I'll hurange them over the phone. Do you happen to know what the Wiseco pin is made of?

The afforementioned Zippers tool steel piston pin's weight is 68 grams, but I can't find it on their website.

Alas, that pin is no more. I called them and they couldn't even tell me who made it for them. "Maybe Axtell". Dead end. Oddly enough, they still carry a .792 pin with a .085 wall and advertise that as for a Sportster conversion. ????????????

I'm also interested to see what your method for removing weight from the piston and pin would be. I've got a couple of ideas in mind, but I'm interested to see what you're thinking."


This part is easy for me but maybe not so much for other people.

As I said, I intend to start with the JE pin. It has a .110 wall. The Zippers pin had a .085 wall and we know it was, at least, somewhat reliable. I'll bore the ID into either: an arch shape, or a parabolic shape, or a simple taper from each end. I haven't really analyzed it yet but I think the final shape will have a max wall thickness of about .100 and a min wall of about .070. Hopefully, it will be in the 72 gram range and save me 20 grams.

The piston will be a bit more complex. I intend to chart the interior, make a print of it, then write a CNC program to cut it down to size.

I help a buddy with his vintage racer and his pistons are not that much different than ours. They are made by Aires and have been CNC'd to lighten the interior. Anything they can do, I can copy.

My CNC is tiny but I have another buddy. I'll come up with the fixturing and cutting data then turn the actually machining over to him.

Did I mention that this is a winter project? When I say it's a winter project, I really mean all winter. Not to worry though, I'm slowly acquiring duplicates of everything so the bike will be ridable for all but a couple of weeks.

Gear Up, Flaps Up,
Walt
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Puddlepirate
Posted on Saturday, October 13, 2007 - 08:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Titanium wrist pins, Titanium Valves, Titanium Spring Retainers, etc, for Big Twin
http://www.stealth-medical.com/auto/productsBigTwi nMotorcycle.htm

Might be worth looking into. There is no mention of weight, except "40% weight reduction over tooled steel", but the pins are $160 apiece.

You wouldn't be interested in doing another set of pistons with that CNC, would you?
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Ilikeike
Posted on Saturday, October 13, 2007 - 11:22 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Titanium is so enticing but just a bit over the top for me. I expect to see the prices continue to come down as it gets more common so maybe on the next build. I wonder why they recommend it not be used for street builds?

If the boring of the wrist pins works out, it will be easy to make a few sets for other people. The key word here is 'few'. I like to help out, but it's not really what I do. It should also be very cost effective since there won't be much setup time invested. The inserts for this type of boring are pricey but I think it will be doable.

CNCing the pistons is a total unknown. I can't commit someone else's machine. Maybe if his usual work is slow he might be interested. Even if he was, I'm not sure if it would be cost effective. I don't expect to see the weight go much below a set of forged slugs that you can buy off the shelf.

I'll certainly keep everyone apprised of how things are going. Right now, the project has hit a significant snag. The Chief Financial Officer (otherwise known as The Wife, so how ya gonna argue?) has informed me that we've driven the charge card past the comfort zone so could I please wait for the next billing cycle to order. Sigh. Ten days and counting before I can even order the stuff and actually get some pistons to start analyzing.

On a cheerier note, Total Seal got back to me. They don't stock rings for the XB12 but will special them for $80.00 per pair.

And, I did get a good start on an eBay intake I picked up. Please go to Engine/Intake. I'm starting a new topic there so not to hijack my own thread.

As Usual,
Walt
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Strato9r
Posted on Saturday, October 20, 2007 - 01:17 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Walt,

Check CP pistons website; I'm pretty sure they make not only a lightweight tool steel pin, but some really exotic ones as well.
Rick.
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Ilikeike
Posted on Saturday, October 20, 2007 - 11:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So, of course, the pins catalog is corrupted and won't download. I sent them an email requesting the info.

Thanks for the tip Rick.

Walt
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