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High Protein posted:Your 'distance the fuel has to travel' thing might be you confusing the bore/stroke with the compression ratio. The compression ratio is the ratio between the available volume in the combustion chamber/cylinder with the piston at the top of its stroke, vs. that when the piston is at the bottom. So with a higher compression ratio, the same amount of fuel/air is compressed more, which leads to a more powerful explosion. A higher compression ratio correlates with more power/efficiency, however I'd say it mostly tells you something about how modern the engine design is. *suck air through teeth* Weeeeellllll.... sort of. Engines with very high compression ratios generally have to run richer than ones with lower compression ratios to prevent detonation, and (as with over- and under-square engines) the very different applications that a big lazy low-compression engine would have compared to a tuned-to-the-nuts high-compression engine would tend to wipe out the on-paper better thermodynamic efficiency of a higher compression ratio. TBH I've never known or cared much at all about bore, stroke or compression ratio on any of my engines because it's really not a factor. Sure i could compare the engine in my current bike (Shiver) with my last one (Mille R) and go "Hmm, yes, the Shiver engine is less over-square than the Mille and runs a lower compression ratio so it's likely to not rev as high or make as good peak power but it's likely to have a better, flatter torque curve and be more tractable round town" or i could just look at the dyno graphs and get a much better idea - or I could just look at the styling of the bikes, which give a way clearer picture of what they're designed for. FWIW I get about the same MPG on the same commute between them because by far the most important factor is the nut holding the handlebars.
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Feb 23, 2015 21:45
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Ripoff posted:I don't see the words "Buell" or "Blast" appear anywhere in there, you dirty liar. Well maybe only the second worst bike! I love my bike though. It does, however, run a little rough sometimes. Every now and then it seems to have an uneven acceleration, and while accelerating sometimes it'll start feeling like it's getting a little kick every 12 or so seconds. It also has a tendency to just die if I have been going in high gears for a while and need to come to a stop. Like the rpms just drop out and if I don't gas it in neutral it'll end up giving up the ghost. I'm going to replace the petcock because I know for a fact it's not regulating fuel flow like it should. Where else should I be looking for these troubles?
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Feb 23, 2015 22:13
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goddamnedtwisto posted:*suck air through teeth* Weeeeellllll.... sort of. Engines with very high compression ratios generally have to run richer than ones with lower compression ratios to prevent detonation, and (as with over- and under-square engines) the very different applications that a big lazy low-compression engine would have compared to a tuned-to-the-nuts high-compression engine would tend to wipe out the on-paper better thermodynamic efficiency of a higher compression ratio. More compression =/= more rich. The AF ratio stays the same, they're just sucking in more air and fuel in general but the extra efficiency is worth it. This is why turbos actually improve fuel efficiency compared to NA (they're just almost never used for this purpose because of cost and complexity reasons but this is slowly changing in the automotive world) - they're ramming in more air and essentially bumping compression. Higher compression needs ignition, fuel and engine temperatures managed much more carefully to avoid detonation; I assume that's why modern bikes are all moving/have moved from a wasted spark, two-coil setup to coil-per-plug, because there's no real intrinsic performance benefit of one vs the other. But there are a million other factors that affect poo poo a lot more than this stuff so unless you're building a bike with a heavily modified engine or something it really doesn't matter to anyone anywhere.
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Feb 23, 2015 22:23
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Slavvy posted:More compression =/= more rich. The AF ratio stays the same, they're just sucking in more air and fuel in general but the extra efficiency is worth it. This is why turbos actually improve fuel efficiency compared to NA (they're just almost never used for this purpose because of cost and complexity reasons but this is slowly changing in the automotive world) - they're ramming in more air and essentially bumping compression. Higher compression needs ignition, fuel and engine temperatures managed much more carefully to avoid detonation; I assume that's why modern bikes are all moving/have moved from a wasted spark, two-coil setup to coil-per-plug, because there's no real intrinsic performance benefit of one vs the other. No, higher compression generally does mean a richer-than-stochiometric mixture because detonation vs deflagration is pressure-dependent, as well as the much greater heating caused in the compression stroke making pre-ignition much more of an issue. quote:But there are a million other factors that affect poo poo a lot more than this stuff so unless you're building a bike with a heavily modified engine or something it really doesn't matter to anyone anywhere. This however is absolutely 100% correct.
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Feb 23, 2015 22:59
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goddamnedtwisto posted:No, higher compression generally does mean a richer-than-stochiometric mixture because detonation vs deflagration is pressure-dependent, as well as the much greater heating caused in the compression stroke making pre-ignition much more of an issue. This is what they use octane for, I thought. You can tune out a lean ping by adding fuel, but I don't think higher comp engines run any richer.
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Feb 23, 2015 23:03
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goddamnedtwisto posted:No, higher compression generally does mean a richer-than-stochiometric mixture because detonation vs deflagration is pressure-dependent, as well as the much greater heating caused in the compression stroke making pre-ignition much more of an issue. You've got the right data but you've drawn the wrong conclusion. Everything you've said is true, but enriching the mixture isn't how you fight detonation. clutchpuck posted:This is what they use octane for, I thought. You can tune out a lean ping by adding fuel, but I don't think higher comp engines run any richer. Yup, this. If richness increased with compression, corollas and poo poo wouldn't be running around with 10.5:1 CR like it ain't no than because it'd make them too thirsty to be marketable. More compression just increases cylinder temperatures and the likelihood of detonation. All of these are manageable, as I said above, provided you have decent octane fuel. When unleaded fuel was introduced, horsepower ratings plummeted across the board because octanes were reduced so drastically and engines lost compression to compensate (emissions equipment didn't help). Bikes cheat to some extent because their camshaft profiles are so aggressive that they can have a very high static CR on paper whilst effectively having reduced compression in practice. Plus bike engines get a shitload of cooling airflow (and very cool intake temps) and can be tuned to run a little less conservatively because bike owners, in general, are far less stupid/neglectful than car owners.
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Feb 24, 2015 00:37
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Slavvy posted:bike owners, in general, are far less stupid/neglectful than car owners. Because we're far more likely to die if something fails while operating
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Feb 24, 2015 02:49
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Wizard of Smart posted:Because we're far more likely to die if something fails while operating I'd say that we are on average far dumber, but most of the retards die off or only ride 200 miles over a summer. Darwin? 
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Feb 24, 2015 04:45
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Chichevache posted:I'd say that we are on average far dumber, but most of the retards die off or only ride 200 miles over a summer. Darwin? Agreed. I've even seen a guy get mad at the parts guy at a shop for telling him his sprocket that had almost no teeth was beyond dangerously worn. vvvvv It's so common that it never even crossed my mind when I was trying to come up with Dumb poo poo. Marxalot fucked around with this message at 05:54 on Feb 24, 2015 |
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Feb 24, 2015 05:11
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Marxalot posted:Agreed. I've even seen a guy get mad at the parts guy at a shop for telling him his sprocket that had almost no teeth was beyond dangerously worn. Riders voluntarily wear no helmet or half helmets, end of story. We are a dumb species.
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Feb 24, 2015 05:36
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Driver's wear no seatbelts while updating facebook in their tinted X5's on the motorway with cruise control set to 100km/h.
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Feb 24, 2015 08:08
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Actually, all other things being equal higher compression ratios give better fuel economy. See for example Mazda Skyactive engines (or for an older, more imperial example, the Jag V12 HE).
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Feb 24, 2015 08:43
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Slavvy posted:This is why turbos actually improve fuel efficiency compared to NA (they're just almost never used for this purpose because of cost and complexity reasons but this is slowly changing in the automotive world) - they're ramming in more air and essentially bumping compression.e. Nidhg00670000 posted:Actually, all other things being equal higher compression ratios give better fuel economy. See for example Mazda Skyactive engines (or for an older, more imperial example, the Jag V12 HE). Yes.
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Feb 24, 2015 09:22
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Wizard of Smart posted:Well maybe only the second worst bike! I love my bike though. The Blast is so bad that Eric Buell had one crushed into a cube as a PR stunt:  You've got a long way to go.
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Feb 24, 2015 10:05
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Why don't my knees fit on these drat bikes? I've been looking for a standard bike to lust over. I'm 6'0" with a 33" inseam (33 just to be different). I've recently done some test-sitting on some bikes and I have found that the indents for the tank rarely fit the height of my knees, with the exception of a few. The CB500F fits me like a glove; so does the Gladius. The idents on these bikes are nice and fitted so they fit firmly against the top of my thighs. The Versys fit so-so, as well as the V-Strom. The NC750X was really uncomfortable - my knees sit level with the bodyline ridge made by the indents - well above the part where your knees should be. It's sad because this is the bike I was gravitating towards. It's cousin, the 500cc adventure themed model isn't much better, despite how well the 500F fit. I had a 440LTD which wasn't the epitome of comfort, but I made due. I want something that hugs my legs well and I would have thought that the taller bikes mentioned above would be fine, but they ain't great. Do some bikes just not fit certain people? Anything you can do to a stock bike to make them more bearable? I'm dumb and this would only be my second bike, and the first that's not 30+ years old.
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Feb 24, 2015 18:55
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Safetyland posted:Why don't my knees fit on these drat bikes? BIkes come in a million shapes and sizes and so do people and sadly if you're gigantic there isn't much you can do. I'm 6" and my gf's hyosung 250 fits me far better than my hornet 900. You can dick around with bar position, aftermarket pegs and seats to try and tweak things but you're best just buying a bike you like to start with.
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Feb 24, 2015 19:06
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Safetyland posted:Why don't my knees fit on these drat bikes? I'm similarly proportioned (6' 34" inseam) and though I've only sat on a few bikes I know the feeling. So far the only thing that has felt comfortable was my DRZ. I've tried the Triumph Tiger and the R1200RT and both of them felt obtrusive and cramped. I think I'm just not going to be comfy on any faired bike.
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Feb 24, 2015 19:12
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Well it's good to know I'm not alone, at least! Here I thought I might have been doing it wrong and could magically change the config of the bike to make it better. Still baffles me that the ergonomics don't work. Whenever I go to buy pants, there are never any 36W/34L, so I know that I'm not some special snowflake. Somebody is buying all the drat jeans/comfy bikes.
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Feb 24, 2015 20:20
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Looks like my SV1K has sprung a leak somewhere between my rear brake reservoir and master cylinder.  ^^ Brake fluid on the exhaust ^^  ^^ Both ends of the hose between the reservoir and master cylinder are covered in fluid ^^  ^^ Bluh?^^ I don't know what to make of this - fluid leaking from both ends of the hose seems kind of ... strange? Is that just the hose dying of old age, or is there more to this? For now the rear brake is working as usual (ie: it'll hold the bike on a steep hill and there's pressure in the pedal).
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Feb 24, 2015 22:24
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Chichevache posted:I'm similarly proportioned (6' 34" inseam) and though I've only sat on a few bikes I know the feeling. So far the only thing that has felt comfortable was my DRZ. I've tried the Triumph Tiger and the R1200RT and both of them felt obtrusive and cramped. I think I'm just not going to be comfy on any faired bike. Try finding a Medium size helmet. prukinski posted:Looks like my SV1K has sprung a leak somewhere between my rear brake reservoir and master cylinder. It is impossible to tell but it's far more likely that the soft pipe going to the MC has torn from age/heat/whatever than the reservoir springing a leak. There's nothing you can do, you have to bite the bullet and drain the system above the MC, take the pipe off and inspect it.
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Feb 24, 2015 22:46
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prukinski posted:Looks like my SV1K has sprung a leak somewhere between my rear brake reservoir and master cylinder. I don't know if it's stock on the SV, but on many bikes there is a clip on that hose, perhaps one is missing. Check the parts diagram. Otherwise, I have to mention, those diagnostic pics are beautiful. Have I been reading too much Dorkroom? Is that a Fujifilm camera and a 35/f1.4?
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Feb 25, 2015 00:47
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Slavvy posted:It is impossible to tell but it's far more likely that the soft pipe going to the MC has torn from age/heat/whatever than the reservoir springing a leak. There's nothing you can do, you have to bite the bullet and drain the system above the MC, take the pipe off and inspect it. I figured it might be something like that. Any telltale signs of fuckedness I should look for in the pipe when it's off? Ola posted:I don't know if it's stock on the SV, but on many bikes there is a clip on that hose, perhaps one is missing. Check the parts diagram. Otherwise, I have to mention, those diagnostic pics are beautiful. Have I been reading too much Dorkroom? Is that a Fujifilm camera and a 35/f1.4? Nah, both clips are there, you can kind of see the top one among the gunk. I'll check if they're on tight enough though. Thanks re: the pics. Nothing special - just a 60D with a 28mm/1.8 and the diffuse Melbourne sun.
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Feb 25, 2015 01:45
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Look for cracks. It will most likely be obvious.
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Feb 25, 2015 02:02
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Yeah it'll be obvious. Check for the clip as stated. If you can't find anything, block the bottom end of the pipe off with something, fit the reservoir and fill it with brake fluid to see if it's leaking through a crack or something. Other possibility is a blown MC and you're seeing the effects of wind carrying the brake fluid everywhere but based on your pics that seems very unlikely.
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Feb 25, 2015 02:18
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Safetyland posted:Well it's good to know I'm not alone, at least! Here I thought I might have been doing it wrong and could magically change the config of the bike to make it better. Sometimes, you're screwed. Get used to it and adapt. I'm a 32/36, imagine trying to find that in bike gear. I ride my ninja 250 like a praying mantis and just look oversized on my fz6. Ed: me on grom, lol 
nsaP fucked around with this message at 07:53 on Feb 25, 2015 |
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Feb 25, 2015 07:50
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nsaP posted:Sometimes, you're screwed. Get used to it and adapt. I'm a 32/36, imagine trying to find that in bike gear. I ride my ninja 250 like a praying mantis and just look oversized on my fz6. Please link to kickstarter for you riding a grim around town, engaging in harmless shenanigans and amusing pranks. tia
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Feb 25, 2015 14:43
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On the other side of the spectrum, the grom is the perfect size for me. I fully intend to test ride one this season, to see how it feels to actually fit your bike.
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Feb 25, 2015 17:20
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nsaP posted:I ride my ninja 250 like a praying mantis Would like to see this, tia
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Feb 25, 2015 17:20
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M42 posted:On the other side of the spectrum, the grom is the perfect size for me. I fully intend to test ride one this season, to see how it feels to actually fit your bike. Ok ok, buddy cop comedy time. You guys ride around the city solving crimes. At least one wacky grom size-related hijinks per episode.
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Feb 25, 2015 17:23
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I'll make puns and short jokes the whole timeSafetyland posted:Would like to see this, tia Dunno if there are actually any pictures of me riding it tbh, I think all I have is video from my perspective. I only have a couple pics of me on the fz6, some from Deals Gap and the others from my buddies photography class project.
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Feb 25, 2015 18:57
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I want at least one episode featuring Gromkour: Grom-parkour.
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Feb 25, 2015 18:59
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M42 posted:On the other side of the spectrum, the grom is the perfect size for me. I fully intend to test ride one this season, to see how it feels to actually fit your bike. If you painted that up to look like an FZ9 or something you wouldn't be able to tell from a distance. builds character posted:Ok ok, buddy cop comedy time. You guys ride around the city
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Feb 25, 2015 19:00
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M42 posted:On the other side of the spectrum, the grom is the perfect size for me. I fully intend to test ride one this season, to see how it feels to actually fit your bike. How tall are you? My fiance is 5' 1" and I wanted her to look at Grom's; she wants to look at scooters.
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Feb 25, 2015 19:18
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5' 4". It's actually average female height in the states, but a majority of everyday bikes are just a little too wide or tall to be completely comfortable (most higher cc dirtbikes/duallies are completely impossible). Especially when pushing them around. I'd vote for the grom instead of a scooter, but I'm a filthy grom lover. Have her take a look at this, too. You can lower bikes a decent amount, if she's a featherweight the lessened suspension travel won't really matter. Don't forget to pull up the forks to maintain the geometry, and get a shortened kickstand. M42 fucked around with this message at 19:51 on Feb 25, 2015 |
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Feb 25, 2015 19:45
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Do I need really nice tires like Pilot Roads if I'm riding a Honda CTX700 (think NC700X)? The Bridgestone Battlax's have worked well so far. I take the bike to its (mild) limits, but it seems like overkill to be paying ~$300+ for tires on this bike.
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Feb 25, 2015 19:51
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They last longer and have better wet weather control.
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Feb 25, 2015 20:09
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For me the value in Pilot Roads is their longevity. I put on a set of PR3s in 2013, they have about 12,000 miles on them, and barring damage I don't intend to replace them this year. This is the front *after* Seattle-Austin-Seattle at about 9000mi - they still look fresh: 
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Feb 25, 2015 20:09
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Chichevache posted:How tall are you? My fiance is 5' 1" and I wanted her to look at Grom's; she wants to look at scooters. My wife is 4'10.5" and she fits on the Yamaha Starbolt pretty good. Also the Grom. No DRZ for her though! I really want her to get a current-gen V-Max, but since she's terrified to even ride cupcake on my Ninjette at like 5mph in a parking lot, that might take some convincing.
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Feb 25, 2015 20:24
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drat, if PR4s have that sort of longevity (combined with their other positive factors), maybe that's the way I should go. My current Battlax set have 4.2k mi on them and they're already starting to wear a considerable amount.
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Feb 25, 2015 21:00
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Radbot posted:drat, if PR4s have that sort of longevity (combined with their other positive factors), maybe that's the way I should go. My current Battlax set have 4.2k mi on them and they're already starting to wear a considerable amount. They're the only tires I buy and I've now bought a set for 3 different bikes. Just got my new set of 4's in on Monday and I'm excited to get them on the bike. 
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Feb 25, 2015 21:08
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