| Author | Message | ||
     Mikeyp |
So, i toasted a rear piston and jug on my 98 S1W (pics are on my facebook... Mike Palladino) I am wondering which route to take. I am considering an 88" motor. I was wondering what are the downsides. I was told they are too much for the street, that they shred tires, and they dont like to be ridden in the turns. Also be careful not to ove rev them. If you have seen my pictures, you will understand that the cases need to be split no matter what. There is too much piston material floating around inside the cases, that it needs to be split and cleaned up throughly. Soooo... Which brings me to this. Do i go the 88" route? Or do i get it cleaned up and go 1250? I want to start with a good foundation, and build off of it. It seems i might need heads too, as im not sure my Thunderstorms can be salvaged. Max HP is not my goal, but i would like to see some sort of improvement for the money im spending. Bulletproof is what i have in mind. I want a strong stout motor that will handle some abuse. I ride my bike hard. I wheelie it, (yes 45 year old holligan that i am...) i ride in stop and go traffic, tear it up on the curvy backroads, and i do a fair amount of highway driving as well...so it seems i need and all around powerplant. This will be a project for the winter, and im gathering as much info as possible, so your input is very valuable in helping me make a decision. I would like to hear from actual BWBers who are running either the 88" or a 1250 and give me your real world expierences on living with them from day to day, and what you would do differntly if you had the chance. Now help me spend some money.  | ||
| Buellistic |
You can not beat CUBIC INCHES !!! | ||
| Mighty_mouse |
Take into account the cost per hp/tq. Don't forget about the other machine work done for the casing. Also more cubes means more need for air flow(bigger cams). Possibly bigger jets and or bigger carb. See what size carb the 88" is using? I learned a lesson in racing that swapping most parts from a 355 SBC to a 406 SBC it doesn't work. Just starved the motor. | ||
| Greg_cifu |
My S2 came with a 1250 kit when I bought it. On paper, it's the identical engine to the Westwind but, you can definitely feel the torque difference that the 1250 barrels make. It's not OMG-fast but, it's stronger for sure. Downside? The barrels aren't as pretty or well matched to the cases as stock. The engine on the S1 is hanging out there and very visible so for me, that would factor into things if I were in your situation. How it will last will depend on how hard you ride it. A strong engine that you only tap into occasionally will last forever. If you beat a stocker all the time, it too will fail. With all that out of the way, if I were in your shoes, I'd be tempted two ways: 88" motor with cleaned-up Thunderstorm heads. or Stock XB12 top end. I think the XB heads would look great in an S1 frame. | ||
| Mikeyp |
Thanks so far for the info. FYI I have a Mikuni on my bike and a force exhaust. I figured I would have to swap the cams as well. I'm guessing a complete 88" would cost me $2500 in parts and machine work give or take with me doing all the labor? | ||
| Cupcake_mike |
mikeyp same thing happened to the rear cylinder on my 99 m2, roached the rear cylinder/piston did you figure out what caused yours? I am still at a loss on mine | ||
| Tony302 |
Not trying to highjack your post, but I am very interested in the 88 is that a complete new case or you take the stock case and get it machined to fit the 88 kit?? I have a 99 x1 would like to eventually do this | ||
| Mikeyp |
Cupcake: Not sure why she blew. Motor had oil in it, and when i took it apart, there was oil in the rockerboxes, so i am assuming it wasnt oil starvation. It might be that she was old and tired, and still ridden hard. lol Tony: Check this site out. Can probably answer some of your questions http://www.nrhsperformance.com/ | ||
| Tony302 |
thanks mikeyp it sure did now I know what I want. | ||
| 46champ |
I have an 88 inch Sportster drag bike. Actually they are 87" but that is a different problem. In order to fit the big cylinders you have to take the motor completely apart and bore the spigot holes to fit the cylinders. There are 2 choices for cylinders a bigger version of the stock cylinder with an iron liner in a aluminum fin assembly, or a cast iron cylinder. The stock clone may work better on a street bike but every motor I have seen that had a cracked case had the iron lined aluminum cylinder. Mine has cast iron cylinders. No cracks after 5 seasons of drag racing a trip to Bonneville and I put it back on the street and rode it as my street bike and put about 5,000 miles on it. The other problem with the bored spigot holes is there is not a lot of meat around the cylinder studs. There have been bikes that have pulled the studs. Another problem is you can easily make more HP than the rods can handle, my bike has Carillo rods that is easily another $800 for rods plus the labor to redo the flywheels. In short if I was just going to do a street bike I would do the 1250 kit and spend the extra money on cams. | ||
| Mikeyp |
Thanks for the info Champ. Im leaning more and more towards a 1250. Im pretty sure the rods and flywheel in my motor now would need to be gone over by a machine shop to make sure they didnt get messed up from my expolding piston. | ||
| Greg_cifu |
There are two ways of looking at big-bore kits: either as a way to increase total torque at the same RPM as stock or as a way to shift the stock torque to a lower RPM. An engine's power is really all in the intake, heads and exhaust. Those can only flow so much volume. If you put a big-bore kit on an otherwise identical engine, the result will be an approximation of shifting the same gross horsepower down in RPM (maybe peaking at 5K RPM instead of 6K). Some see this as "starving" the engine. I see it as creating a torque monster that snaps out of corners at moderate RPM. I find this kind of engine much more satisfying overall than high RPM power. Lets face it: if you want real horsepower, you can't be serious if you're riding a pushrod twin. My S2 with the 1250 jugs is just a brute between corners on a tight road. Except for falling on its face at 5K, it's a hoot to ride. My long-term plan is to T-storm the engine (heads, cams, ignition), install stock T-storm exhaust on it and ride. I don't expect it to make any more overall power than a stock S1W but, I am guessing it will all come in about 10% lower in RPM. No undue load on the rods, the crank or any of the other parts. | ||
| Dannybuell |
XB heads are better than thunderstorms. | ||
| Buellistic |
They flow better because they have smaller valve stem valves ... | ||
| Radon30 |
I was told xb heads are better in stock form but if your going bigger cubes , you should have some head work performed anyway, thunderstorm heads and xb heads no difference at that point. | ||
| Firstbuell |
my '99 M2 is now an 88 [90?, I can't remember.....] sponsors JT&S built it with stock carb & intake + Stage2 NRHS heads/236 cams/V&H/ham can 100+ hp/100+ lbs-ft with 40+ mpg give Jim or Terry a call - they REALLY know what they're doing! (Message edited by firstbuell on November 11, 2013) | ||
| Splatter |
"They flow better because they have smaller valve stem valves ..." Thats not what these guys say: http://www.hammerperf.com/ttxlheads.shtml#2004-Pre sent "03-up Buell XB Heads 62cc chamber, 1.810" diameter intake valves, 1.575" diameter exhaust valves These, and the 04-up XL1200 heads, are the best performance heads for Sportsters and Buells ever offered by Harley Davidson. They retain the same valve diameters as the Thunderstorm heads (previously the best heads), but the ports have been improved significantly with a floor that's been raised even higher and an even more gradual radius through the bowl. These two changes work together to greatly reduce port turbulence, because they reduce the difference in the length of the floor and the roof, thus reducing the difference in velocity. On the flow bench, these heads flow about the same as a Thunderstorm head, but the improved velocity and reduced turbulence often add up to a 4-5 horsepower advantage over the Thunderstorms when comparing a stock head to a stock head." They show pictures of the ports and you can really see the big differences between an XB and a Thunder Storm. | ||
| Hootowl |
Valve stem diameter, not valve diameter. I don't know whether the valves are indeed smaller, but a smaller diameter stem would allow for greater flow. | ||
| Splatter |
You don't read good. Hammer says its about the differences in the port design not the stem diameter and the XBs flow about the same as the Thunder Storms but make more power because its a better port. Go look at the pictures the ports are totally different. | ||
| Rocket_in_uk |
Mikey call Wes and Pammy at Cyclerama. Pammy's X1 is 88 inch and likely the best ever built! Rocket in England | ||
| Buellistic |
Look at the casting marks in the ports, LOOK THE SAME TO ME ... Valve head sizes(ex/in)are the same ... Only difference "i" see is valve stem sizes which a little is smaller which makes a big difference in flow !!! Talk to Pammy at CYCLERAMA for the last word on this !!! (Message edited by buellistic on November 11, 2013) | ||
| Rocket_in_uk |
Also Mikey, most of my stock capacity performance stuff is listed in this topic and it's worked for me in much the same way you ride. http://www.badweatherbikers.com/buell/messages/406 2/725784.html?1383316471 Going 88 inch is the best way to go for ultimate street performance in my opinion (based on the research I did back when, and somewhat regret not doing so at the time) but it's essential you have strong foundations. All this stuff is fairly obvious and common place so not hard to source the right components and put them together. Two things that are of utmost importance to whatever you do. Make sure you choose the right cams for the riding you do. I chose Andrews N9's when they were not so popular but well liked, and I could not be happier all these years later. There are better cams (marginally) now as I understand it but get the cams and head tuning right for the 88 and just build it bullet proof. The last thing you must do is fit the XB rocker cover breather set up as it will puke if you remain with the stock Buell / Sportster covers like I did, and still haven't changed yet! Well, I don't thrash it quite like I used too. Rocket in England | ||
| Buellistic |
Rocket_in_UK: In my youth "i" had a 1958 XL "883" do the rod thing at 8000 RPM !!! What a mess !!! | ||
| Splatter |
"Only difference "i" see is valve stem sizes which a little is smaller which makes a big difference in flow !!! " I'm curious buellistic how many heads have you flowed and how much difference did you see from Thunder Storms to Xbs? | ||
| Dannybuell |
I have 102,000 miles on my 96 S1, the perfect city bike. I have 20,000 miles on my 09 1125 CR, the perfect road bike. With an 88" you will still want a sixth gear for the freeway. | ||
| Jayvee |
Boy what a fun problem to have... Can't really lose, with either choice | ||
| Kalali |
You guys are talking past each other.. This is from the Hammer Performance: The stock intake port on a 2004-up XL or 2003-2010 XB head improves on the Thunderstorm port with an even higher floor and more gently radiused roof through the bowl area. Valve diameters remain the same however stem sizes were reduced to 7mm. Its the size of the valve stem that makes the difference. | ||
| Splatter |
"Its the size of the valve stem that makes the difference." Where do they say that? Seems to me like their sayin its the port thats improved. Heres the whole thing they show pix of how the Xb is better than the Thunder Storm:  A stock Thunderstorm chamber improves on the Lightning chamber by unshrouding the much larger valves. The squish band is also taken out to 15 degrees although it's still a rough, uneven casting with a lot of overhang around the perimeter, making it difficult to achieve a good squish clearance. The unshrouding resulted in a 67cc volume and requires a matching domed piston to get 10:1. Also, you can see in this picture how the roof through the bowl area is more gently radiused, as compared to the picture of the XL1200 chamber above. Look near the stamped numbers and compare.  A stock XB/04-up XL1200 chamber is a pear shaped bathtub and has a 62cc nominal volume This creates a squish band on each side of the chamber and leaves plenty of material for cutting 15 or 30 degree angles to match angled dome pistons. Despite the compactness of the chamber and the large valves, the valves are not shrouded. Also note how smooth the radius is through the roof of the bowl in both ports, as compared to the XL1200 and Thunderstorm heads pictured above. These are the best heads HD has ever produced for Sportsters and Buells  The stock Thunderstorm intake port improves on the Lightning & 88-03 XL1200 intake port with a somewhat higher floor and more gentle radius through roof area in the bowl. Valve sizes were increased as well.  The stock intake port on a 2004-up XL or 2003-2010 XB head improves on the Thunderstorm port with an even higher floor and more gently radiused roof through the bowl area. Valve diameters remain the same however stem sizes were reduced to 7mm. | ||
| Blake |
I don't like the 88" option. Really like the 1250. More power and better cooling, win-win. Tune for mid-range and enjoy. | ||
| Rocket_in_uk |
I can't speak for the bathtub head but if you are going to want to gas flow a head, in my opinion the hemi head is not so bad, it's just it's options are a little more limited when comparing to the bathtub shape as there are more options commercially for performance parts seeing as it's still a current head in use. It matters not about the valve guide or rough casting really as they will be sorted when flowed. So what is it that makes the bathtub head the choice of that company? Obviously they're displacing 62cc as opposed to 67cc so higher compression is easier to achieve, and the depth and shape of the 62cc head will allow for more piston choice I'd assume, again adding to ease of compression options. That said, if we are talking street use what does it matter especially in America where fuel octane ratings are not ideal for 10 odd to 1 compressions anyway. At best you don't really need to be up near 11.1 for street and reliability unless yer a fooking nutter on a bike. Nor for economy if you do the miles. So if you have a pair of ThunderStorm heads then don't exchange them for bathtub heads is my opinion unless you've money to burn, as the benefits are beyond what you need for what you can do with TS heads if you already have them. Of course, if you have bathtubs already then stay with them and get stuck in. I went with stock compression when I did mine despite the many modifications. This is the real draw back of the TS head as there's not a lot of options for raising the compression significantly without getting pretty involved. But you don't need to for a high HP street bike anyway. Lastly, I can't help but think even if it's true a bathtub head will flow better than a TS head, there's not some commercial embellishment in that companies choice seeing as XB heads are readily available and TS ones are not. And let's face it. You're not after a LSR - are you? Rocket in England |
