| Author | Message | ||
     Mikej |
I don't know all the "secret" stuff a local shop does, but they rarely put in untouched performance rods. Heat tempered maybe, shotpeening maybe, balancing definitely, deburring and general cleanup usually, dimensional fit and check always. Shotpeening usually is designed to reduce the possibility of surface imperfections from turning into major catastrophies, if I remember correctly. Also a form of work hardening if I also recall that correctly. Sometimes they run a set of rods, then remove them and rework them a bit more once they've settled down some. Like I said, part art, part science, part experience, not stuff you get from a cereal box or from peeking over someone's shoulders. | ||
| M1combat |
Gotcha... Problem is I don't have a good shop around here that I know of. Anyone know of a place in Flagstaff or Phoenix? | ||
| Bads1 |
I read a artical awhile back that a reader had the very same kind of question about dry clutch,but a different type a bike.The reply was,keep with what you have.The race teams use them just because they are easily taken apart and put back together again,no messing with fluids to time consuming.Those super bikes if not launched off the line right can result in a shot clutch or glazed over. | ||
| Fullpower |
M1 try to find an s& s stroker you can ride. you will be amazed at how quick they spool up. mine will turn 7000 rpm, at revs so quick, it loses traction. if you want to wheelie, you have roll on the throttle. if you snap it open it just spins the tire... lightening the flywheels makes a tremendous difference in the character of a motor. i have read that the bolted together multi-piece crankpin and flywheel assembly does not like to rev real high. so i dont think 8000 rpm is sustainable with a 3-13/16 stroke sportster motor. i have flogged mine at 7000 a lot, but have since turned down the rev limiter to 6500. the light bulbs last longer if i dont wind it up that high. | ||
| Jmartz |
The more stroke the more stress on the lower end at change-direction-time and thus the more vibration. A stock or stroked lower end will likely not have a long life if spun to 8K. Rods are common to fail as well as the crankpin in some cases. To reduce the forces at the lower end, the combined weight of the pistons, pins and rods need to come down. Remember that the iherent weakness of the roller bearing design is that the journal is little (1.25) compared to a plain (2.25) and bolted rather than monolithic. Consider the Japanese designs. Ultra short stroke super high redline. Weak at the bottom, strong at the top. Even so, these will out accelerate a Buell with only half the displacement of the race is longer than 200 feet. | ||
| Blake |
"Consider the Japanese designs. Ultra short stroke super high redline. Weak at the bottom, strong at the top. Even so, these will out accelerate a Buell with only half the displacement of the race is longer than 200 feet." A Ninja 500R or a Suzuki GS500 will out accelerate an XB9? A Bandit 600, the 600cc Seca II, an SV650, or even a CB750 will out accelerate an XB12? Nope, not even an XB9. I know, you are talking about the repli-racers. Okay, so let's talk about them for a minute. They are great bikes for the track for sure. What kind of acceleration do they provide when whacked wide open from say a top gear cruise at 4K rpm? Answer... underwhelming. Where the XB9 is already putting down 40rwhp, and the XB12 is making 47 rwhp the IL4 600cc repli-racers barely manage 20 rwhp. Roller bearings and their inner races can be as large as needed and are far superior in performing their mission (reducing friction while transferring load) compared to plain journal bearings. That's one reason why the little 600cc Japanese engines cannot achieve the amazing fuel efficiency that the Buell engines do; plain journal bearings are parasitic power eaters. The inefficiencies associated with higher engine speeds also contribute to their inferior fuel mileage. There are other benefits to roller bearings on the crank... Lose oil pressure with journal bearings and the bearings will likely very soon be toast. Not so with roller bearings. | ||
| M1combat |
But roller bearings can't handle as much outright load? On the oil pressure issue, it's pretty rare to lose oil pressure in an HD twin. When it does happen it's not JUST the crank bearings that go. I'll most likely stick with roller's though as I plan on using slipper pistons, light rods and Ti pins (If I can prove to myself that the engine is rigid enough to use the slippers). I would imagine it is because the crank only has one journal and theoretically shouldn't flex much side to side. I would like to move to a flywheel that is both stronger and lighter than the stock piece. I noticed a flywheel on racing motorcycles that they claim is 3lbs lighter than stock... I wonder if it's monolithic or will use a roller bearing? What about that S&S one mentioned above? What does Aaron use? The stock part? At that price for the 88" kit I would imagine so. On the loss of oil pressure and journal bearing... I can attest to their lack of lifespan w/o oil... I have a 351C 2V sitting next to the Mach-1 it originally came out of after starving the rear main bearing at just over 8K RPM (yes, on a stock engine). Damn Ford for designing it that way. When I rebuild it I'll be modifying the oiling system... Whoda thought a stock Mach-1 2V car would do JUST under 100 in second gear  . Anyway, I digress, and I also don't wanna waste any more bearings... | ||
| Rocketman |
What kind of acceleration do they provide when whacked wide open from say a top gear cruise at 4K rpm? Answer... underwhelming. What kind of acceleration does an XB 9 or 12 provide when whacked wide open from say a top gear cruise at 4K rpm? Answer... underwhelming when the CBR600 rider kicks it down two cogs. See Blake whilst it's great to feel your arms being pulled out of their sockets on an XB it's also great to feel your whole body thrust into the horizon on a high revving IL4 And you just bled all over a good topic with your nit picking comment. Rocket | ||
| Dynarider |
Blakes just afraid to downshift. | ||
| Easyflier |
You can downshift an XB too.  | ||
| Hippo888 |
Blake, Whack open any equivalently sized Japanese sportbike at 4000 rpm and you'll kiss any Buell goodbye. I can't see my XB9S (954cc) keeping up with a GSXR1000 (998cc) or an XB12 keeping up with CBR1100XX or Hayabusa. Those things spin very, very fast from 4000 rpm into their powerband thanks to their (relatively) tiny flywheels. As for dry clutches -- they're noisy, delicate and sound like rocks are rattling loose in your engine. I'll take a primary chain slapping over the racket a Ducati makes any day! | ||
| Bads1 |
Hippo Blake was comparing 600cc repliracers.Not the Jap big liter bikes. | ||
| Hippo888 |
Oops - my bad. Apologies for not reading more carefully. | ||
| Hippo888 |
Ok, I got some numbers. All data is from Motorcycle Consumer News. Please see: http://www.mcnews.com/mcnews/depts/Dec03PerfIndexPart1.pdf http://www.mcnews.com/mcnews/depts/Dec03PerfIndexPart2.pdf Bike/0-60mph/0-100mph/quarter-mile (secs.) XB9R /3.94/9.22 /11.83 XB12S /3.63/8.73 /11.54 CB750 /4.47/na /12.74 Bandit600 /3.97/10.72/12.16 SV650S /3.61/9.07 /11.63 SV650 /3.74/9.75 /11.89 The SV series is surprising close to the XB series in straight-line performance. The XB's are better than the other Japanese bikes, but man, those are some seriously (CB750, Bandit600) sad-ass bikes. Things get more realistic when you look at a someting like the last generation CBR: CBR600F4i/2.89/6.61/10.59 The current generation 600's are faster, but I don't have the published data. | ||
| Dynarider |
Ah who cares, everyone knows Ninjas suck   | ||
| Blake |
"But roller bearings can't handle as much outright load?" Sure they can, if they are sized/designed for it. My point is that an engine using journal bearings has those bearing designed for the loads they must support, no more, no less. The same is true for roller bearings. BTW, I'd stay away from titanium alloy pins. Titanium is half as stiff/rigid as steel and bending/flexing of a bearing is definitely no-bueno. Rocket, You just cannot help but get personal in these discussions can you? You don't like my posts? You want to preach the gospel of the IL4? Go the frig elsewhere. Capice? This my friend, is a Buell enthusiast's site. Don't like it, leave. There are plenty of other sites where you can join the worshippers of the impressive Japanese IL4 top speed and peak hp. If you want a tiny turbine-speed crank, by all means, go for an IL4 repliracer, but don't presume to chastise me for sticking up for my preferred motorcycle in the face of derogatory remarks. Jmartz fired the first volley in this tangentiation, not me. I cannot fucking believe we are still having this same fucking inane asinine discussion... Twit: The Jap 600cc IL4's are faster than a 1200cc Buell. Buell Enthusiast: So what, I like the power delivery characteristics of the Buell. Twit: <ustters some passive-aggressive personal insult aimed to belittle the Buell enthusiast> and on.. and on... and on.... FUCK OFF TWIT!!! Thanks Hippo; you reinforced my point. There is no real substitute for displacement if you want power at low engine speeds. Whether an IL4 or Buell twin, you need liter sized engines to make downshifting (to pass) optional. As to the MCN numbers. They are not corrected to eliminate the effects of variable atmospheric conditions. Using the MCN numbers to compare different machines is thus unreliable. Neither would I say the bikes referenced are "sad ass". They, simply put, are not race bikes, some are even air/oil cooled. Dyna, "Blake's just afraid to downshift." Original thought?  | ||
| Dynarider |
Original thought? Nope But I liked it the first time I read it. Plagiarism isnt always a bad thing. | ||
| Wyckedflesh |
What kind of acceleration does an XB 9 or 12 provide when whacked wide open from say a top gear cruise at 4K rpm? Answer... underwhelming when the CBR600 rider kicks it down two cogs. And if you drop one gear on the 12 it jumps up and howls forward faster then the CBR600...that is of course unless the CBR600 that tried that tonight flat shit his pants at the howl that rocked his world as we both dropped a gear (two in his case from the drop back he did in shifting) to go around a truck up through Black Canyon. Now granted after I shifted to 5th and hit 100 I let off and he kept going off into the sunset. | ||
| Blake |
Dyna, Then you will appreciate my original response to that comment. Remember what it was? | ||
| Rocketman |
I wasn't preaching the gospel of the IL4's, merely pointing out the stupidity of your comment in an otherwise interesting thread. Funny how I'm the one always accused of the personal remarks. In your post above you called me a twit and told me to fuck off. Nice touch big guy. Rocket | ||
| Jmartz |
We were discussing how to make the stock Buell motor perform better. Its unique design is the reason for its level and type of performance. As Buell enthusiasts seeking to enhance performance we need to understand and compare what we have in order to consider our options. I remember the old Porsche roller bearing motor of 356 fame. Historically not a durable design, dropped by the company after a few years of production, now sought by collectors with passion. My Kaw Z1900 had a roller bearing crank and made 80 RWHP. I seem to remember it being faster than my S1 of the same output. This engine weight (mass) thing will make or brake change of speed rate (acceleration). My Yam R1 has a ghost of a motor. There is nothing there. It so light and stores so little energy in its rotation that cutting the throttle is nearly equivalent to braking (slipper clutches?). Yet, let some fuel into that beast and you'll be at 140 in a few seconds. | ||
| Benm2 |
The largest forces produced inside an engine are those that occur during combustion. If that weren't true, the engine wouldn't make any power. (ie the parasitic losses would exceed the gain) S&S sells crankpins at larger-than-stock diameters, with wheels to match, where the stroke can be customized. They sell bearings also. For the industrious, companies such as NSK, SKF, etc. make roller bearings in larger diameters than Buell uses. If you've got the time & patience, design your own crank. The shorter stroke will allow for larger journal diameters, but by the time you get to the outside of the rod, its getting pretty big. Case clearance might be an issue. You'd have to make alot of your own parts. Roller bearings will be larger than equivalent load rated journal bearings, as they have no rollers and the loads are supported by point-contact. Also, every roller bearing will eventually fail from fatigue, and will need replacement. The "bearing" in a journal bearing is the oil, and also requires periodic replacement, but generally does not require taking the engine apart to do so. Most journal bearing wear occurs when the oil's not there, on startup, before the pump pressurizes the system. Lastly, roller bearings are expensive relative to journal bearings. Bearing steel (to improve reliability) is fancy stuff, with alot of process into their manufacture, and there are more parts to a roller bearing. If you believe that losing oil pressure to a buell crank will not result in failure, try it on your own. While you may get a few more seconds than the journal bearing, it will fail. | ||
| Jmartz |
I always thought HD had resorted to rollers due to the engine's large temp swings resulting from being and air cooled powerplant. Rollers are looser and oil pressure is low. I know you can make an HD type motor stronger but its going to be get bigger and heavier and I doubt it will propel the bike its in much faster. The Ford 351 was intended to be used in trucks and has big diameter journals. The Chevy 350 has smaller diameter (2.25) journals and always outperforms the Ford (with similar accessory parts) and is known to be more durable. Something a bout the speed of rotation the larger the diameter at constant rpm. | ||
| M1combat |
"The Ford 351 was intended to be used in trucks and has big diameter journals. The Chevy 350 has smaller diameter (2.25) journals and always outperforms the Ford (with similar accessory parts) and is known to be more durable. Something a bout the speed of rotation the larger the diameter at constant rpm." The Windsor is a truck engine, the Cleveland was made for Trans-Am road racing when Ford realized they needed more displacement (I think it replaced the 289?). The moment you modify the oiling system the Ford is more durable. If you use the right factory designed heads on the ford (2V vs. 4V) for your application the Ford outperforms the Chevy. The only time you would use the 4V heads would be outright racing at a place like Le-Mans or Monza or some other VERY fast racetrack. Any other time you want the 2V heads as they will give you better (read less peaky torque) in a more useable range. Most people look at the HUGE ports on the 4V and assume they must be for racing, that is incorrect. In any case, learn some race history and you will find that Ford's problems with roadracing were in the handling areas (Which is why they made the Mach-1, but didn't get much of a chance to race it). Ford is the winningest company in the history of motorsport. There's a guy to this day that runs a Mach-1 against late model Camaros, Corvettes and Mustangs etc and does quite well (yeah, he even wins sometimes ). It's not even modified a WHOLE lot... darkhorse racing, check em out. | ||
| Hootowl |
I had a 351C4V in my ranchero. It was bone stock as far as I know. Thing ran like a raped ape. | ||
| M1combat |
Sooo, I think I have gathered that I need an S&S crank and may need to switch over to the journal bearing instead of the roller? I intend to use good oil anyway so I would imagine that the life of that bearing won't be so short as to fry my engine unless the pump goes. As was mentioned, either bearing strategy will result in a failure if it gets no oil. The 3-13/16 stroke is still a must though. Unless anyone has anything more to add on the internal parts of the engine... The external rotating assembly... The virtues of a dry clutch... I don't mind the sound. What about durability? Will a belt primary and dry clutch last as long as a chain setup? Since my goal is to reduce inertia in the rotating assemblies... Does anyone make a set of pullies that are lighter than stock, smaller than stock (I'd like to change the primary ratio a little so I can hit 160 or so once I have more power) AND stronger than stock? If not, I can settle for the same ratio on the primary and just go for lighter/stronger and then change the ratio on the secondary. I'm willing to keep the chain if someone can convince me that the belt is a bad idea. Aright, I gotta work... | ||
| Benm2 |
Why would you change to journal? Lots of money. Stick with the roller. Belt versus chain? Which lasts longer, the primary chain or the buell drive belt? While its a broad parallel, a chain running in an oil bath should have a comfortable life. I would think that an open drive belt will also have life issues. Look at car design. If its safe to assume that timing belts & chains are designed for the same load ratings, then the difference should be in life. My old Toyota 22RE engine had a timing chain with 200K miles on it. The shoes looked worn at rebuild (tensioner), but the sprockets and chain looked almost new. My old Golf with a timing-belt driven cam needed replacement at 60-70K. For the car, the belt setup was cheaper (for the manufacturer). Since you'd be doing your own, that wouldn't be true. Its your cash though. Spend it the way that makes you happiest. | ||
| M1combat |
It won't be an "open" belt as such. It will have holes in the cover as an aide to cooling but I think I can duct those in such a way so I don't get water/"much dirt" in there... and taking off the cover to clean it once a month or so isn't an issue as there will be no oil in there. However, it's starting to sound like the chain is the better idea though as reliability is a concern. I know... I want everything. I am a firm believer in the fact that if I make just the right compromises in certain areas I'll end up with exactly what I want. Erik and Co. already did the hard stuff. The point of changing to journal would be to have a monolithic crank shaft which should be stronger. Unless I'm not understanding something... I like the lower friction of a roller. Are they as strong? I still don't understand why they don't counterbalance the crank like you see with a "normal" crank... Wouldn't that be best? Why do we need all that "extra" material on the journal side? | ||
| Blake |
Good post Ben. I would clarify one thing. Where you said "Also, every roller bearing will eventually fail from fatigue, and will need replacement." Again, given that the bearings are designed/chosen to provide equivalently long service lives their is no difference in the longevity between the two in normal consumer applications. In applications where the engine is never or rarely ever shut down (like in big diesel generators) and there is always a good high pressure supply of oil, a properly sized and properly made journal bearing will last indefinitely. They are THE standard in the world of automotive engines. They do have a lot of advantages, just not in efficiency or as you stated in the unlubricated mode. Also, where journal bearings use an inherently smaller diameter, how does their length compare to that required by roller bearings? Consider the effect of that parameter on a single crank pin V-twin. The shorter and stockier you can make the crank journal, the stiffer and stouter the crank will be right? M1, Hitting top speed has little to do with your primary's rotating inertia. The inertia will affect the rate of acceleration, but not top speed. The efficiency of the primary drive system WILL affect top speed. You might want to compare the efficiency of a wet chain versus a dry belt. Here's where I would take my advice on making a Buell go faster... What do the Pro Racer's machines have. None have dry primaries as far as I know. If there were any significant advantage, and if the rules permitted (Pro Thunder allowed unlimited engine mods) wouldn't they have tried that? I dunno, maybe the rules prohibited modification of the clutch, maybe José Q. will see this and chime in. He seems to keep up with the Buell racing classes' tech rules. Ever see how common it is for top fuel cars to lose their blower drive belt? | ||
| Jmartz |
M1 my 351 discussion was about journal (crankshaft) strength and durability not heads and performance. I've had Mustangs for many years. The Chevy engine is better looking though. Here is my recipe for a severe stock mod. Cut the flywheels on the side around the outer edge w/o changing OD but removing material where it affects spin-up mostly. Use Ti rods and Jims 3 hole pin. AAC jugs 3 & 5/16 diameter, slipper pistons and light pins. Dynamic balance assembly to 55% (high rpm biased). Have Aaron CNC port your heads and install larger valves and use the hollow stem valves he supplies with Ti collars (std. springs). For a cam the RS 580 seems to be the ticket. Install S&S rockers and have Hyperformance custom make you a set of Ti pushrods (I have a set, $75 ea.). For a spark module use a V-Thunder that fits all in this cone and is laptop programmable. Use a bigger carb and free up the exhaust. For a trans pulley use the all aluminum Baker 26 and get as set lighter wheels like Marchesini Magnsium like I have. Alternatively you could add the Baker 6. I enjoy mine, shifts better and allows for some ratio manipulation for better use of you extra power. I like the Zipppers oil pump but the stock post '97 and its 2000 iteration are Ok. A short stroke 3 5/8" S&S engine with 4' bore and zippers dual runner heads would be where I wold want to start as I have already messed with the stock config. enough. |
