| Author | Message | ||
     Firebolt020283 |
Cityslicker also puts his bike threw more abuse than most others do... | ||
| Blake |
We use flex joints on satcom antennas all the time. They permit huge ranges of motion. We're talking nearly +/- 180 degrees of motion, and they too are under some serious temperature cycles as they tend to heat up with 10KW of RF energy passing through them. These are not steel, which would be much more durable. They are aluminum or copper, both of which are more susceptible to strain hardening and ensuing crack propagation/failure. | ||
| Hughlysses |
It's also worth mentioning that rotary joints have been around since at least the 1930's that can withstand 300 PSIG and 725 degree F superheated steam (articulated steam locomotive applications), so IC engine exhaust wouldn't be much of a challenge if this method is used. | ||
| P47b |
I am somewhat interested in what the tire temperatures and pressure might be at in operation. Expressly in extended time intervals. Tire wear times would be shortened. | ||
| Court |
>>>You apparently have your own very bitter supply and are snorting it directly in powder form. Precisely the reason I stay at arm's length in these banter-flicts. The day's of having a civil discussion on line are great memories. Many ideas that are patented never see the light of day and simply serve as conduits to other ideas. Many things that do see production are patented under names you would never find searching. Like I said . . this is not the first rodeo. | ||
| Hughlysses |
The day's of having a civil discussion on line are great memories. ONE guy (1 post out of 65) posted a snotty, disparaging comment. Otherwise, I thought we've been having a very interesting, friendly, civil discussion. Wouldn't it be easy enough to ignore the one? | ||
| Blake |
Rotary joint config would need to be on the pivot axis; that's probably not feasible with moto-exhaust at swingarm pivot, not what is shown in patent sketch. Or you could use a linkage comprised of three total rotary joints; probably too expensive. Flex joint is simple and light and cheap. Rectangular section would seem to be optimum. | ||
| Hughlysses |
Although it's not shown on the "full bike" view, they actually show the rotary joint as an alternative in the patent:  BTW- you can download a PDF of the full patent here: http://www.freepatentsonline.com/y2010/0270098.html | ||
| Blake |
Matt, I don't see a lot more weight of consequence. Remember that with the swingarm, mass closer to the pivot axis is less unsprung, more sprung. | ||
| Blake |
Hugh, Whoa! Now we're talking! Too cool. That'd be the way to go! | ||
| Reepicheep |
Hmmm. Should I search for patents belonging to Harvey Mushman?  (Great movie, and is in the "on demand" queue at Netflix.) (( I need to watch it again and look for the bike I have in the garage... bet it is in there multiple times... )) | ||
| 46champ |
After looking at fig 6 it looks like the exhaust components could be replaceable thru the the removable portion 404 the inside would probably be lined with stainless steel sheet and air cooled on the outside, exhaust would not be going in the structural part of the swing arm. | ||
| Court |
>>>Wouldn't it be easy enough to ignore the one? You're right. My apologies. | ||
| Doerman |
mass closer to the pivot axis is less unsprung, more sprung Good news for me. That means the weight of my belly is not contributing to handling problems! | ||
| Stirz007 |
No one took a crack at the bearing heat question, so I'll give it a go - probably talking out my arse, though. Your 1125 has a disc brake mounted to the wheel somewhat close to the wheel bearings. That thing can get red-hot and dissipates much of the heat through the wheel. This does not seem to create excessive bearing heat (most of the time). I'd venture that the exhaust either does not generate enough heat, or that heat can be somewhat isolated from the bearing. Again, Confederate has been using this arrangement for a number of years, granted the Hellcat is not a race bike. (The newest Hellcat will be unveiled this Friday - I'm guessing you can have one for a mere $75K or so). And I'd agree that not all patents actually become usable products. I'm kinda leaning to this particular patent not going too far. The whole muffler in a swingarm seems like the long way around the barn to me, but you never know - come up with an idea, patent it, and maybe the thing will have legs - and maybe not. | ||
| Blake |
Bearings inside the engine get hot. Jet engine bearings get hot. Duty cycle of swing arm bearings is very, very light. Well-sealed high temp bearings and lubricant surely exist to handle the heat. No reason heat transfer could not be minimized through intermediate insulating material(s). Here's a wild idea: The swingarm must be supported by a spring, well why not ditch the bearings and employ a springy structure to provide for swingarm motion while at the same time acting as the rear suspension spring. The rear shock then would be mainly damper with, if needed, a small spring for preload/sag adjustment. | ||
| Pushrodpete |
Wow. One post and suddenly I'm the Death of the Internet. Cool beans! Anyhow, if you were to read my bitter, snotty, sarcastic post again, you might in fact realize that at no time did I disparage Erik Buell or any of his ideas. Hell, if he makes a road-going 2-stroke, I'll vote for him for Pope. My earlier post was merely mocking the fanboy postings (here and in various other threads) that assert that anything done by Buell must de facto be a Motorcycling First. And yea verily other manufacturers MUST be cribbing from Erik (even if the other bikes predate him....) Examples include fuel-in-frame, underslung exhausts, inside-out brakes, etc..... And BTW, my "bitter supply" right now is a Boulevard Pale Ale (sipped, not snorted). Cheers! | ||
| Blake |
So then you could have swingarm also acting as spring and exhaust, three for one.  | ||
| Hughlysses |
Pete- fair enough. Let's just say some of our members are understandably VERY sensitive to criticism of Erik and if you didn't wish to be perceived as disparaging & sarcastic, you could have worded your post so as to be less likely to be taken that way. It is possible to be impressed with Mr. Buell and actually LIKE him without being a "fanboy", isn't it? Boulevard Pale Ale sounds interesting. My wife and I just finished a growler of Southern Tier Pumking ale and are feeling very benevolent ourselves! Happy Thanksgiving! | ||
| Blake |
>>> Wow. One post and suddenly I'm the Death of the Internet. Wow, an entirely new straw man for you to defeat in argument. Well done! You're on a roll! >>> the fanboy postings that assert that anything done by Buell must de facto be a Motorcycling First. Still arguing against the same straw man, albiet slightly evolved? You win, he loses! Be happy and content in your meaningless victory over your own imagination. Well done! The flames of your wild exaggeration and imaginary realm of debate strike fear into straw men everywhere! (Message edited by Blake on November 24, 2010) | ||
| Stirz007 |
You could use a torsion bar at the swingarm pivot to get the desired "springiness" described. I use torsion bar on my purple yerple, works fine. Don't need an auxiliary spring, just adjust the turnbuckle. Easy peasy, and 'off he shelf'. | ||
| Mikef5000 |
A torsion bar rear suspension?! Now things are getting interesting! | ||
| Stirz007 |
KT Components - softspension. You still need a damper for the suspension to work, but you can get rid of the springs (well, really change from a coil to a torsion bar). | ||
| Sparky |
Heck, just go with quarter-elliptic springs as the swingarm fork. Just think: - no bearing at the pivot needed - no external springs needed. but it would need: 1) a simple way to keep the axle parallel with the arm mount, perhaps something as simple as a link like the UniPlanar system would suffice?, and 2) a damper of some sort. Didn't the "World's Fastest Indian" bike have something like this? This is fun stuff... | ||
| Hootowl |
The swingarm exhaust also appears to be a secondary exhaust. Perhaps a good bit of heat would be dissipated by the first exhaust canister, and the second canister in the swingarm would simply provide additional sound attenuation and direct exhaust into the low pressure region behind the tire? Witness the cobbled together secondary exhaust on the 1190RS in the teaser video. There could be something to this. From the outside looking in (as most of us are) it seems like a possibility. | ||
| Fireboltwillie |
hootowl, i remember Jens from Pegasus Racing noting that at european racetracks that had noise limits, they had to run a second muffler to meet the restrictions. and i also remember erik, on his facebook page, noting that this motor is loud and would most likely need a second muffler to meet epa sound regs. then again, i may have been nipping at the rum again.... | ||
| Trojan |
Some 1125 aftermarket exhausts won't get you into a track day here in the UK and are even too loud for racing! For racing the limit here is 105db and most track days won't allow anyone over 100db to get onto the track. Some have a 98db limit which even stops some stock bikes complying. Buell UK famously organised a Buell tack day at Donington a few years ago but forgot to mention that it was on a 'quiet day' (98db) so only about two of the assembled Buell owners were allowed to use their own bikes on track! H-D UK had to let their demo fleet be used by everyone else to prevent a riot! Europe has very strict noise laws for road and track use and I think in order to comply with those the hugger/muffler/swingarm would have to be huge, ugly and heavy unfortunately. | ||
| Blake |
Matt, Do you recall the whisper quiet XBRR muffler? It was a conventionally sized under-slung Buell muffler. The acoustic resonance design coupled with a liquid cooled engine and two separate mufflers should be incredibly effective and in no need of anything huge or ugly. Certainly nothing beyond what other twin cylinder superbike repli-racers are employing. The quiet laws are absurd. Engines are whisper quiet, tires, especially truck and trailer tires scream like turbines. Anyone who lives near any moderate to high speed roadway knows this all too well. I will say that I was impressed with the eerily quiet of downtown Tokyo. Their buses are near silent. It was very nice in the city. I enjoy downtown NY too though. Not so quiet. The 98 dB, more than four times quieter than 105 dB, just doesn't make sense at a race track. Every 3dB drop in allowed noise level equates to a halving of audible noise levels. Certainly the same rationale should be used as is afforded airports and heavy industrial sites. Anything less would seem hostile to motorsports. I guess when folks stop paying to use the uber quiet venues, things might change for the better. I very much doubt Erik Buell Racing is going to invest in a very expensive development program for its first outing with a street legal machine. They'll likely use a conventional second muffler as depicted in the teaser video. But who knows what the future might hold? | ||
| Blake |
>>> Some Why you'd single out aftermarket exhausts for the Buell 1125 is odd. That statement surely applies to any serious sport bike and the wide range of aftermarket mufflers available. Are you saying that because some aftermarket exhausts won't meet sound limits that Erik Buell Racing cannot design a moderate weight stock system that would? Huh? (Message edited by blake on November 24, 2010) | ||
| Stirz007 |
Sparky - the KT set up I think would meet your intent. It replaces the swingarm pivot on the softail - I can say first hand that on the two instances where I replaced the coil over spring suspension with the torsion bars, it really cleaned up the rear end and dropped a couple of pounds. It works great and is reasonably idiot-proof. I'm sure this could be adapted to almost any swingarm - Hugh - I'm guessing that first can (Mark 36) is probably the catalytic converter. You probably wouldn't want to have that in the swingarm due to heat. I'm running the EB race exhaust on my 1125 tracker, and was told by "anon" on this very site that it will meet the 105dB limit. Trojan - do they actually walk around with dB meters and black flag the bikes?? That's gotta suck. |
