| Author | Message | ||
     Foximus |
So I have a somewhat assembled bike... I believe it's a s1w, but I'm not quite sure. Are there any easy ways to tell exactly what is what? The rear cylinder was toasted and replaced but I'm not sure if they changed the heads to something different or if they are not the domed lightning heads to begin with. The only castings I see are D on the front head and C on the rear head, as well as what I believe is 96Y on the flat area next to the exhaust ports. Also, my front cylinder is blowing oil BAD... I'm to led to believe this is my oiler ring gone bad... My compression is about 190 in the front and 165 in the rear (which is the now good and rebuilt cylinder) . Now I'm assuming the front cylinder is higher compression because there is all that oil in the cylinder making a better seal, but is there a chance the rear cyl was rebuilt with a non domed piston making the lower compression? Now, I am a jetski mechanic, and on a 2 stroke if we had a bad compression ring we would just attempt a hone with a new ring at first to avoid the cost and labor of a full bore and rebuild. Usually it works. I talked to a harley builder and he said there is no use... a hone and a new oiler ring wouldn't fix it... 99% chance I need a bore and new piston. Agree or disagree? So my questions are.. A) How do I know what heads I have? B) Is there an easy way to tell what pistons I have without removing the heads? Since domed lightning pistons seem hard to find, is there a chance he rebuilt the rear cyl with a flat top or something else piston ?(hence the lower compression) C) Am I looking to do a full bore and piston job because of a bad oiler ring? D) If so, what pistons should I go with? I normally race my engines (jetski) with wiesco, and they are great... or should I stick with factory harley here? Any of that make sense or am I all mixed up? | ||
| Cyclonemick |
S1w's came with Thunderstorm Heads and if you have those they should be Black! Only Thunderstorm Heads are Black! As for the rest of the questions someone else should chime in. But I would suggest checking out the Sponsors on this board for New Internals (pistons, rings, and such) if you decide to go that route. | ||
| Tbolt98 |
Won't the VIN tell you exactly what you have... how about some pics!?! | ||
| Court |
The 17 digit VIN will tell you precisely how it was originally built. | ||
| Foximus |
The Heads are black. But so are a lot of other heads. The guy who burnt and replaced the rear cyl, was a MMI harley tech, so he could have had a slew of parts to throw on it. The front is the original silver cylinder, the rear is now a black and polished fin variety. Why would I have thunderstorm heads and not lightning heads with the domed piston? Or am I confused and they are the same thing? I thought the lightning heads were a 10* cast squish band and the thunderstorm heads were 15*? Or are my pistons flat? The numbers on the motor right above the primary are SS11V2000090 And the VIN is 4MZSS11J4V3200090 | ||
| Foximus |
I'm lacking a card reader to get my pictures off my camera now... =\ | ||
| Cyclonemick |
Thunderstorm Heads are a better performing Head than the Lightnings. Regular S1's had the "Lightning Heads but the S1W's had the Better, More flow Thunderstorm Heads. If they are indeed BUELL Heads the Thunderstorms were black and all others were silver, If he used aftermarket heads then I could not tell you! As for the squish someone else will have to help you out! Someone will surely look up your vin for you and help you out or call your local "Stealership" and ask them to run your vin for you! | ||
| F_skinner |
It is a S1 not S1W | ||
| Foximus |
And how do you know that Skinner? And so what does that mean you think? The heads are black and they are cast with 96y... I'm waiting to figure out exactly what I have so I know what pistons are the best to buy, (and what type... dome, flattop...etc) And then the heads are coming straight off for me to port them. I also want to know what kind of valves would be good to use, if I can upgrade or if its even worth the money. | ||
| F_skinner |
The VIN starts with 4MZSS for an S1 and 4MZYS for S1W | ||
| F_skinner |
Nothing, save the fact the the previous owner may have put different heads on it or painted them
Agree | ||
| Foximus |
Well I mean, what does that mean... is there any casting numbers I can look at to tell me what heads they are? And thanks for the replies skinner. | ||
| F_skinner |
I thought, and I could be wrong, the S1W Thunderstorm heads were 98YV?? or something. The 96Y I thought was the Lightening heads. I could be wrong on all of that. Since you have to take them off maybe you can post pics up to let us see. | ||
| Foximus |
Do both use domed pistons? Either way Im not sure it matters to me as From what I can tell I'd like to go to the 2004 XL/XB heads as those are the best flowing heads, and the best options for machining a good combustion chamber... Then I can port those. Just want to know what I should buy a rebuild kit for. | ||
| F_skinner |
The XBs used domed pistons. I do not believe the tubers had them (I am sure someone can confirm or deny that for me). The XB heads will give you a lot of bang for your buck. | ||
| Foximus |
And as far as I know the XB heads just bolt on, only need for change is some adjustable pushrods...? Well I may or may not try to take a head off today... seeing its my only transportation till the end of the week I will probably go with "may not"... | ||
| Brinnutz |
You need a not front motor mount for the XB heads. http://www.americansportbike.com/shoponline/ccp0-p rodshow/16032.html I will say that it is a great improvement overall. | ||
| Foximus |
Ah yes... I knew I needed the new mount as well... I just dont like the fact that you really need to send the heads away to get a squish band machined into them to make them really worth it. Ah well. I'll just stick to porting my heads and a rebuild for now, once I figure out what heads and pistons I do have for sure. | ||
| Foximus |
Well that just made my decision much easier... I went out for a quite mild ride over to campus... Did a nice little wheelie in front of the Gym... and by the time I had gotten to the parking lot I was running on 1 cylinder. Awesome. I have no modes of transportation. Gonna start tearing it down to figure out why. | ||
| Foximus |
Nevermind that... just pulled a ignition coil wire loose. | ||
| Easy_rider |
Standard sporty heads have "fins" in the top. Thunderstorm heads have that area open. I thought I posted pics here about a year ago but can't find them now. Here's a standard head..  If you really need it I can go take a pic of a thunderstorm head. I'll probably do it sooner or later anyway since this comes up about once a year... | ||
| Foximus |
Definitely have the fins. If i grind them off... does that give me the extra 20hp? =] But seriously this means I am just running regular flat top pistons with 9:1 compression? What type of domes do I have? Do you have a picture of the domes per chance? And... assuming I buy the correct ____________ pistons for these heads (flattops?) If I go ahead and get XB heads later, do I need to switch to domed pistons? (Message edited by Foximus on October 12, 2010) | ||
| Easy_rider |
I've got the pistons in my basement. I can shoot you a pic. They are slightly dished IIRC. I can't tell you about the rest with any sureness. I think you can run the older pistons, but once you're in deep enough to change the heads you may as well change the pistons to get full benefit. I'm sure it's been posted a time or two, but I can never recall. | ||
| Foximus |
Any other confirmations? Just regular sportster pistons then? Or should I plan on buying a different piston for when I go to xb heads? | ||
| Phelan |
To further drive the nail in, '96Y were "lightning" heads, which were basically standard Sportster heads with extra material added in the combustion chamber to raise the compression with flat tops to 10:1. '98Y heads were thunderstorm heads. Ironically, the '98-'03 XL1200S used a dual plugged version of the lightning head rather than the thunderstorm design. Anyway, As mentioned above, use new pistons with the XB heads. Squish band can help but isn't a huge deal. Whatever direction you go, buy the pistons first and have the heads matched second. So if you decide to go with Wisecos or Thunderstorm pistons, you can have the heads matched for optimum performance. Personally, I'd just stick with no squish and new stock XB12 pistons, but big performance isn't as "big" of a deal to me as cost. My ideal build would be XB heads/cyls with XB12 pistons, SE .551 cams, and an XB12 primary gearing. That'd be plenty for me  . | ||
| Oldog |
foxi: buell heads Tstorm say buell on the underside I believe near the intake or exhaust ports. | ||
| Foximus |
ok... so xb pistons are not flat top? Or do XB heads work with flattop pistons naturally? grrr.. After all this I know i wont be able to get XB heads for a while as they seem to be impossible to find anyway and are quite expensive new. Plus I'm not sure how much there is to gain over my ported lightning heads... really just seems to be a bigger valve to be the only gain. | ||
| Littlebuggles |
We need to get Preybird1 in on this conversation since he just did his engine, Phelan and Brin also did theirs so they should bea able to give fresh advice on some of your questions. You said earlier "From what I can tell I'd like to go to the 2004 XL/XB heads..." From my conversations with PB1, he got the XL heads (for less $$) and had a much easier time sourcing them because the XB are so hard to find. My understanding was they are the same except for needing to be properly drilled for the carb bracket and front motor mount. So you just get the special motor mount (Brin posted the link for) and are good to go. I'll shoot Preybird1 a PM and link to this thread, I think he will be able to answer your remaining questions. I'm not trying to discount anything the others have said so far either. Everyone contributing in this thread have all been here a long time and have a lot of good info, lots of knowledge gathered in their many backgrounds and experience. | ||
| Foximus |
Right.. Thanks buggles... Ive found a coulple sets of XL heads on ebay for decent amounts.... I may go for them if I can figure out what to do with pistons. When I build my jetski race engines I use a yamaha engine but then I deck the jugs and use a special wrist pin, and then I bore using big bore Kawasaki flat top pistons... (some people use even bigger bore sea doo pistons) So i'm relatively adept in figuring out how to build a decent motor, my only problem is I don't know the first damn thing about harley motor tolerences, and I have never cracked open the inside of mine to see what I actually have.... If I can get my hands on the parts with a micrometer in hand... then I'm on my way to building me a ported motor, and maybe break that 110 hp line. (I was also thinking about mounting a side draft mikuni non CV carb... maybe...) | ||
| Foximus |
Also... whats people's experience with buying forged pistons vs cast? Is the weight savings on forged worth it? or is it just too much expansion to deal with in an air cooled motor thats reaching 300*? |
