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RandomFact314 08-14-2011 01:33 AM

Can you switch gears too soon?
 
I usually switch at 2500 rpm but sometimes go up to 3000.
Is this too low of RPM to switch gears at? Is there a too low?

Also, is there too low of a speed to be in your last gear (5th for me)? because Iv got into 5th @ 34 mph

I believe the transmission I got is a S40 B000

Bare with me, This is my first manual car since I was 15 and I drove like a tard back then anyways :thumbup: I don't really know any of the rules to driving a standard yet, I just know how to get where I'm going. I just learned like 3 days ago that I'm suppose to not coast up to lights with the clutch pushed in and to never use the clutch in gear to keep you from rolling down hill at a light

Thanks!

aporigine 08-14-2011 02:33 AM

The manual Hondas I've owned, I've developed a pretty good rule of thumb: in ordinary driving I'd shift into 3rd, 4th, 5th around 25, 35 and 45mph. Cruising gently on a flat road, I'd figure 40mph to be the "bottom of 5th gear". 30mph was the bottom of 4th, etc.
Now i realize that there will be diverse schools of thought on this, but something I remember from riding Harleys (which develop addictive torque right off their idle of about 800rpm) is that there was danger on those machines of using overlow RPMs. While the engine felt fine ... even sweet ... ker-puttering at low revs in high gear, the main bearings were potentially subject to a condition known as "brinelling". This occurred when a bearing moved slowly under high load, and the oiling system could not keep up. Metal would contact metal under high shear stress, with bad consequences for the longevity of the bike's bottom end. I realize that the oiling systems and bearing speeds of a honda four-banger are different from those of a huge leisurely single-pin V-twin, so I don't know if there is an equivalent "yellow zone" for your Honda, in which the engine isn't obviously lugging or juddering, and yet oiling becomes marginal.
It becomes a game of compromises. you can safe your low-rpm high-load driving to some degree by using heavier oil; a common trick among V-twin motorcyclists. This will of course offset an overall quest for max mileage. Just as a practical safeguard I would not use moderate loads (like ordinary unhurried acceleration) below, oh, 1800rpm indicated, and I wouldn't put my boot into it until the low 2000s. At 34mph in top gear, what are your rpms?

One thing I remember about Honda manuals is that they had very benign behavior on hills. I never had a problem starting from a stop uphill. The clutch feel was excellent, and I could transition my right foot from brake to gas in plenty of time while finding the "sweet spot" with my left foot, neither stalling out nor overrevving and dragging the clutch. If this intimidates you, here's my Top Gear Top Tip (grin): Find a flat place with nobody else around to hurry or distract you. With your right foot off the brake ... and initially off the gas as well ... ease the clutch out until you findwhere it just starts to 'grab". In my Hondas that point was typically around 60% of the clutch pedal's travel, with 100% being floored. Your leg will develop a muscle memory of that point. When it's time to start uphill in for-real traffic (green light, usually) you'll reflexively let the clutch out to the point just shy of engaging. Then when you get off the brake to give it some gas, you'll be *right there*, and neither roll back nor wear your clutch absorbing "panic revs". I almost never resorted to using the e-brake as a backup, the exception being a particularly nasty 20-degree grade with some (bad word) in a minivan deciding that 18 inches between his vehicle and mine was plenty. (mumble mumble) Slushbox drivers...
Practice away from trafic, and it will all become clear, Grasshopper. (big grin)
cheers apo

RandomFact314 08-14-2011 03:11 AM

Quote:

Originally Posted by aporigine (Post 256041)
The manual Hondas I've owned, I've developed a pretty good rule of thumb: in ordinary driving I'd shift into 3rd, 4th, 5th around 25, 35 and 45mph. Cruising gently on a flat road, I'd figure 40mph to be the "bottom of 5th gear". 30mph was the bottom of 4th, etc.
Now i realize that there will be diverse schools of thought on this, but something I remember from riding Harleys (which develop addictive torque right off their idle of about 800rpm) is that there was danger on those machines of using overlow RPMs. While the engine felt fine ... even sweet ... ker-puttering at low revs in high gear, the main bearings were potentially subject to a condition known as "brinelling". This occurred when a bearing moved slowly under high load, and the oiling system could not keep up. Metal would contact metal under high shear stress, with bad consequences for the longevity of the bike's bottom end. I realize that the oiling systems and bearing speeds of a honda four-banger are different from those of a huge leisurely single-pin V-twin, so I don't know if there is an equivalent "yellow zone" for your Honda, in which the engine isn't obviously lugging or juddering, and yet oiling becomes marginal.
It becomes a game of compromises. you can safe your low-rpm high-load driving to some degree by using heavier oil; a common trick among V-twin motorcyclists. This will of course offset an overall quest for max mileage. Just as a practical safeguard I would not use moderate loads (like ordinary unhurried acceleration) below, oh, 1800rpm indicated, and I wouldn't put my boot into it until the low 2000s. At 34mph in top gear, what are your rpms?

One thing I remember about Honda manuals is that they had very benign behavior on hills. I never had a problem starting from a stop uphill. The clutch feel was excellent, and I could transition my right foot from brake to gas in plenty of time while finding the "sweet spot" with my left foot, neither stalling out nor overrevving and dragging the clutch. If this intimidates you, here's my Top Gear Top Tip (grin): Find a flat place with nobody else around to hurry or distract you. With your right foot off the brake ... and initially off the gas as well ... ease the clutch out until you findwhere it just starts to 'grab". In my Hondas that point was typically around 60% of the clutch pedal's travel, with 100% being floored. Your leg will develop a muscle memory of that point. When it's time to start uphill in for-real traffic (green light, usually) you'll reflexively let the clutch out to the point just shy of engaging. Then when you get off the brake to give it some gas, you'll be *right there*, and neither roll back nor wear your clutch absorbing "panic revs". I almost never resorted to using the e-brake as a backup, the exception being a particularly nasty 20-degree grade with some (bad word) in a minivan deciding that 18 inches between his vehicle and mine was plenty. (mumble mumble) Slushbox drivers...
Practice away from trafic, and it will all become clear, Grasshopper. (big grin)
cheers apo

Yeah I know where the sweet spot is on my civic, my brain remembered it from my CRX back about 6 years ago. I don't have any problems on hills I just enjoyed using the clutch to keep me up because I always thought it was funny to rock back in forth at the light before other cars crept up on you to let them know you DO roll and for them to stay off your arse a bit ;)

Thanks for the tips on when to change gears, I figured that it was bad I just didn't have any science behind it, just a "sounds painful sputtering in such a high gear" :thumbup:

SentraSE-R 08-14-2011 11:57 AM

As Aporigine says, it's a balancing act, dependent on your engine's torque and your transmission's gearing. I try to start accelerating in the lower gears at about 1500 rpm, keeping the % engine load at about 83, and terminating at about 2500 rpm. That's in the fat part of the BSFC plot. Too much load in the 1500 rpm range will pound your main bearings flat, and revving above 2500 rpm wastes gas.


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