| Author | Message | ||
     Turboglh |
went and looked at a motor today for my friends sportster. From the vin on the motor its a run of the mill s2. The heads are off and appear to be lightning heads however (quench band, buell casting mark, head is plain silver not black powdercoat). Cams should be regular sportster, like an m2. So simple upgrade to minimum thunderstorm specs would be pistons and heads correct? Thoughts on if this upgrade is worth the time? Heads are off already, so its just a matter of swapping pistons, gapping rings and bolting on the new heads. | ||
| Ratbuell |
I thunderstormed my S2 and am very happy. Thunderstorm heads and pistons X1 cams Re-jetted Using S1W ignition box It doesn't rev as quickly as my S1W, but that's a function of both the taller gearing (different sprockets) and the heavy flywheel...but I'm very happy with the way the bike runs now. It's a great cruiser. It's no hooligan...but it is an S2, after all  If you want I can pull my stock cams out of the box and get you the part numbers, so you can ID what's in the motor you're working on. I *think* Sporty/S2 cams, M2 cams, and Thunderstorm cams are all different...but I could be wrong. | ||
| Essmjay |
My S2 has thunderstorm heads, SE cams, Dyna ignition. Keeps up with my S3 but feels completely different. I wouldn't just swap to new pistons without having the jugs honed to match. Or maybe a 1250 kit. | ||
| Rex |
I would like to have the 1250 kit with the XB heads... | ||
| Ratbuell |
I posted that I put in new pistons assuming nobody would/could swap pistons without machining. I'm betting Chris knows that, too. | ||
| Turboglh |
I left out the obvious things like machine work, gaskets, head bolts, etc. But I guess they're not obvious to everyone, so good looking out. Yes, plan would be SE cams, new ignition, rejet, hone/bore, and possibly take the time to set the quench clearance. Not sure if I feel like playing around with base/head gasket thickness (to set the quench clearance) and the potential lifter/intake alignment issues that may crop up. On the topic of cams, my understanding was X1/99+ S3 got the .497 SE cams, M2 got regular sportster cams (but got thunderstorm heads after 99), while S1's, S2's and early S3's got regular sportster cams with either lightning or sportster heads(minus the S1W). That should cover all the various combos and power levels available. Budget is about $500-1000, and that includes replacing the various missing parts (primary tensioner, upper gasket kit, pushrod tubes, ignition module, carb rebuild/rejet, and some wiring work) I don't think I can make all of that happen, plus a 1250 kit. Maybe not even a set of used heads, pistons and some machine work. Good to know the power is there if the work is done, now to see if I can work some $ magic and squeeze all of this in. Thanks all. | ||
| Ratbuell |
Don't worry about quench and all that - unless you're going to throw boost to it at some point, it's overkill for a street ride. When I did mine, I got new TS heads and pistons (with rings and complete valvetrain). I cc'd the heads. I measured the (stock S2) cylinder heights. I had the machine shop match a head/jug/piston (and machine the jug as needed) to get the closest match possible. Then I slapped it together, and I've been riding it for about 10k miles since  And FWIW, my stock cams (yeah...I never throw anything away) are Sportster "D" cams. Pull them out and look at the side face of the lobe, and you'll see "1D", "2D", "3D", and "4D" stamped into them. Gaskets are cheap; Al at American Sport Bike is your friend. If you're doing pushrod tubes, get the billet bases too. The stock one-bolt bases SUCK. I've also done an XB rockerbox conversion with black boxes from a '10 Ulysses - used two front boxes because the rear box made the PCV valve hit the tank. And riding it today with the annoyingly loud but happily-breathing uncorked Supertrapp...the GD thing runs GREAT. The X1 cams are a great match to the heavy flywheel and the chassis weight of the S2. 2200 rpm? Torque. 5000 rpm? POWER. Happy world | ||
| Madtex |
Here's what I did to 99 Sportster. Thunderstorm Heads,pistons(.30 over)and cams, Mikuni carb,screaming eagle air intake, Crane single fire ignition, TorqueMaster spark plugs and Thunder Header exhaust. It runs strong and fast. It dinos at 90 HP. I've changed the front sprocket/belt pulley to one with more teeth since the dino, to slow the rpm's down for highway/cruising comfort. Although I've been thinking of gearing it higher. I did all that back in '09. I'm very pleased with my creation. |
