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Hi, I just bought a 2002 MT insight and was wondering how exactally to execute the shifting pattern with 1st 2nd and right to 5th(other than just doing it ;)), and what are the advantages to doing so?

Thanks!

Greg
 

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I never figured out any advantage to this because you need to run the engine at a higher speed in 2nd to get to a suitable speed in 5th and you end up doing one of those things, either #1 hitting 5th gear at an inefficiently low speed, or #2 running too fast for the best efficiency in 2nd gear.

If I need decent acceleration for passing or merging into a road and I reach my speed in 2nd or 3rd gear and 5th gear is a suitable engine speed for that gear would be the only time that I'll skip gears. Going from a gear that is geared for a max of 70mph at redline to the second overdrive seems like quite a jump to me.
 

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I've never done that particular sequence but have many times done a 1,2,4,5 sequence with my hondas.

The Insight is geared so incredibly high that it would be very difficult to accelerate once in fifth (from second), not to mention that it would require a fierce amount of assist and no lean burn untill the stress was relieved. I see no real benefit.
 

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I recently purchased a 2000 Insight w/ 5 spd. The transmission is failing-- w/ 3rd unusable. (Knew it when I bought it-- price was right). So, in the meantime have been using the 1-2-4-5 sequence all the time. The car is quite drivable with that sequence under most circumstances. Doing that allows for keeping rpms under 3000 most of the time, and allows for good use of the electric assist as well. My battery is the original and its not very strong, and this pattern seems to preserve the charge in the top third of the indicator bars. Yet, it allows the assist to be used to advantage.
 

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I never do the 1, 2, 5 shift but...... I often use a 1,2,4 shift in town. It really depends on the road itself. If its a level stretch of road and I will be able to keep a steady speed for a bit without having to stop at another light then I will accelerate fairly hard and fast from a stop in 1st and 2nd...then jump right to 4th at around 35mph and go right into lean burn (great for roads with a speed limit of 35-40mph). I find that I can average a higher MPG number this way. The extra fuel used to accelerate harder is offset by entering lean burn faster and being able to stay in it longer...the heavy acceleration is for a very limited distance and is easily offset by the longer lean burn run.

If you are going to have to stop again in a block for another light ect then that technique won't be beneficial. I also find that by watching upcoming lights and coasting/charging as efficiently as possible I can keep the pack charge up ( I don't downshift to save wear on the transmission, I just get as much regen as possible from the gear that I'm in and then go to idle stop from there).

Here's a shot of my FCD from yesterdays run around town...56 Deg F. outside, no cold air mods ect. 20.0 miles all in town driving using the 1,2,4 method whenever practical.



Hodakaguy
 

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I have an IMA inhibit switch which is on most of the time. I keep the throttle at 70%, and I upshift at 3000RPM while accelerating. This results in a 1-2-5 pattern only when my cruising speed is around 39mph. Even at higher speeds, I'll skip 4th.
 

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I never do the 1, 2, 5 shift but...... I often use a 1,2,4 shift in town. It really depends on the road itself. If its a level stretch of road and I will be able to keep a steady speed for a bit without having to stop at another light then I will accelerate fairly hard and fast from a stop in 1st and 2nd...then jump right to 4th at around 35mph and go right into lean burn (great for roads with a speed limit of 35-40mph). I find that I can average a higher MPG number this way. The extra fuel used to accelerate harder is offset by entering lean burn faster and being able to stay in it longer...the heavy acceleration is for a very limited distance and is easily offset by the longer lean burn run.

If you are going to have to stop again in a block for another light ect then that technique won't be beneficial. I also find that by watching upcoming lights and coasting/charging as efficiently as possible I can keep the pack charge up ( I don't downshift to save wear on the transmission, I just get as much regen as possible from the gear that I'm in and then go to idle stop from there).

Here's a shot of my FCD from yesterdays run around town...56 Deg F. outside, no cold air mods ect. 20.0 miles all in town driving using the 1,2,4 method whenever practical.



Hodakaguy
I agree. Depending on traffic, I either use grandma mode (light throttle, shift at 2000 rpms) or 70% throttle and 1-2-4 or 1-2-3-5 depending on my target cruising speed.

The only problem is that I'll get some net battery loss from latter method. As long as I get a highway run of 20 miles or so to pump it back up every 10 days or so, no problem, but I have occasionally entered forced recharge during those stretches when I don't leave town for an extended period.
 

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I typically skip 4th gear when in city traffic. My technique is to shift below 2000 RPM and as soon as the clutch is out I flick the throttle to encourage the computer to give me some assist, and then back off the throttle until just before the assist drops out (you get a feel for it). I do this through 1, 2, and 3, and then shift into 5 for cruising at the 60 km/h speed limit (37 mph).

Note: this does mean that you don't always keep up with traffic while accelerating, and you can get people trying to push you down the street for the first block or so until you get up to speed.

After a while you'll find the method that suits you and the traffic that you drive in best. The Insight is a good fuel economy instructor as it provides you with lots of direct feedback.

Good luck.
 

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I never could understand the 1,2,5 concept. I often skip 4th, or sometimes 3rd, especially if there is a downgrade to help me along, but I'm not organized enough to follow a 1,2,5 regular routine.
But using MIMA or other methods to disable assist during accelerations helps overall mpg a lot. Assist helps acceleration but increases the mpg only slightly during acceleration, but there is a larger "hit" on mpg later when the battery is regen-ing.
 

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I would recommend against any sequence other than 1-2-3-4-5. The transmission synchros are not going to be happy about jumping gears, particularly if you've got the engine spun up in the previous gear. The gear dogs will also get beat up by this practice. The result is exactly what stevedaniel reported in his post above. The transmission will eventually not engage particular gears and/or will violently disengage under load.

If you're intent on skipping gears to get that last bit of MPG from the car I highly recommend using a double clutch technique (clutch out and back in between shifts). That will prolong the life of the synchros and help prevent dog wear. However, it will not completely prevent the damage.
 

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I don't tend to use the 1,2,5 method... but I do understand the concept of where it can be beneficial... Personally I prefer other methods / techniques.

The concept is to get to the highest steady MPG condition as soon as possible... once in 5th gear , further acceleration is at a snails pace ... if there is any further acceleration at all ... and you shift into 5th gear at the lowest MPH speed that allows lean burn ... not the 40+ MPH most people use for 5th gear... and while in 1st and 2nd gear you are maximizing Assit... once the level of IMA assist drops from max, the 1,2,5 method has you leaving the 1,2 gear.

The major flaws that prevent the 1,2,5 method from working in a beneficial way for people are many... here are the biggest ones I see.

#1>
Just like P&G driving techniques this method depends on maximizing and increasing the 5th gear lean burn time... The hard 1,2 acceleration is a negative ... it is only a benefit if it significantly increases the 5th gear lean burn time enough to compensate.

#2>
Max Assist is used during the 1,2 hard acceleration period ... if there isn't enough IMA battery charge to get this max Assist the method suffers.

#3>
The use of IMA assist is generally only a MPG net benefit when the source of the IMA battery SoC was not a larger negative than the assist gives.

#4>
1,2,5 is not a method to keep pace with surrounding traffic ... surrounding traffic conditions can easily destroy any potential to use a 1,2,5 method for a net benefit... the same is true for P&G.

#5>
The harder acceleration of the 1,2,5 method often teaches the wrong approach to general road way acceleration ... and better MPG driving ... if the driver is not careful ... they will pick up bad habits... these bad habbits can easily counter / negate any benefit that might have been seen from the 1,2,5 method itself.
 

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#1>
Just like P&G driving techniques this method depends on maximizing and increasing the 5th gear lean burn time... The hard 1,2 acceleration is a negative ... it is only a benefit if it significantly increases the 5th gear lean burn time enough to compensate.
I agree, which is why I only use it when conditions warrant.

#2>
Max Assist is used during the 1,2 hard acceleration period ... if there isn't enough IMA battery charge to get this max Assist the method suffers.
I avoid this method once I get below 50% SOC.

#3>
The use of IMA assist is generally only a MPG net benefit when the source of the IMA battery SoC was not a larger negative than the assist gives.
I'm not sure what this means. In around town driving, the 1-2-5 method will have a negative net impact on SOC. The normal background charging on a decent highway run with replenish this. As long as I have a highway trip every couple of weeks, I avoid forced recharging.

#4>
1,2,5 is not a method to keep pace with surrounding traffic ... surrounding traffic conditions can easily destroy any potential to use a 1,2,5 method for a net benefit... the same is true for P&G.
If surrounding traffic is moving quickly, 1-2-5 is the best way to keep up/out of the way. If surrounding traffic is accelerating slowing, the I revert back to grandma mode. It's just a matter of using the right tool for the job.

#5>
The harder acceleration of the 1,2,5 method often teaches the wrong approach to general road way acceleration ... and better MPG driving ... if the driver is not careful ... they will pick up bad habits... these bad habbits can easily counter / negate any benefit that might have been seen from the 1,2,5 method itself.
I'm not sure what to make of this. Lot's of techniques are bandied about on this board. I assume that we are all adults and can process the information properly.
 

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I would recommend against any sequence other than 1-2-3-4-5. The transmission synchros are not going to be happy about jumping gears, particularly if you've got the engine spun up in the previous gear. The gear dogs will also get beat up by this practice. The result is exactly what stevedaniel reported in his post above. The transmission will eventually not engage particular gears and/or will violently disengage under load.

If you're intent on skipping gears to get that last bit of MPG from the car I highly recommend using a double clutch technique (clutch out and back in between shifts). That will prolong the life of the synchros and help prevent dog wear. However, it will not completely prevent the damage.
Good point. One of the benefits of also driving a '73 VW is that double clutching and rev-matching are second nature.

Having said that, I use this method less than 25% of the time since it doesn't lend itself to all traffic conditions.
 

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I'm not sure what to make of this. Lot's of techniques are bandied about on this board. I assume that we are all adults and can process the information properly.
I agree... there are a variety of different approaches to the same goal ... we are not all the same ... some people are better suited for some methods than other methods ... and whatever someone likes to do and works for them... I say great... go for it... but don't be too discouraged just because any one particular method does not work equally well for you as it did for other people.

#3>
The use of IMA assist is generally only a MPG net benefit when the source of the IMA battery SoC was not a larger negative than the assist gives.
I'm not sure what this means. In around town driving, the 1-2-5 method will have a negative net impact on SOC. The normal background charging on a decent highway run with replenish this. As long as I have a highway trip every couple of weeks, I avoid forced recharging.
To expand on this.

The electrical power kWh of energy that are used for IMA assist has to come from somewhere ... as long as it is not a PHEV mod ..... the OEM system ultimately derives all that IMA electrical power from the gasoline.

The path works a bit like this:
Mechanical power produced from ICE ... converted to electrical power by the IMA motor acting in regen ... control MDM electronics control the flow of electrical power .... the NiMH batteries get charged .... latter the NiMH batteries are discharged ... the control electronics control the flow of electrical power to the IMA motor ... the IMA motor converts it back to Mechanical power during assist.

The best ideal case would be to get ~80% of the original mechanical power back out ... the worst case in practice is about only ~40% of the original mechanical power gets back out as mechanical power after the cycle is complete.

If the electrical energy to charge the SoC of the IMA battery comes during methods like forced regen ... where you are loosing MPG and ICE output power in order to generate the electrical power ... and by the time the cycle is complete you will get back out less than you took... so even though the use of Assist gave a MPG benefit during the use of the assist it is only a net benefit if one also includes what is lost when the electrical SoC energy for the use of IMA assist is generated.

For instance ... if for one reason or another you have to brake... the conventional friction brakes recover none ( 0% ) of that mechanical energy ... at which point anything the Regenerative brakes can recycle is better than 0% ... even if it were as low as 1%.

Now one should not over use brakes ... because conserving the existing momentum you already have is more efficient ( 100% ) than trying to recycle some smaller % of it... but if you need to use the brakes for any number of good safety reasons than regenerative brakes are much better for overall vehicle efficiency than friction brakes are.

Regenerative braking as described above is the easy one.

Another option which is more debatable and difficult to quantify real time ... is the use of small amounts of back ground charging when the ICE is in its peak efficiency point like in lean burn ... this pulls power away from the higher efficiency lean burn operation in order to offset some of the power used by the ICE during much lower efficiency operation such as rich burn... this is more difficult because it is not as clear cut as the regenerative braking is... it gets much more complicated very quickly.

What is an example of an overall negative impact ... is if the forced regen forces you out of the more efficient ICE operation ( lean burn , etc ) ... than you would have been MPG wise better off not having the regen or the Assist you would have later used it for.

It doesn't matter so much if the SoC is 90% , 50% , or 10%... but where the energy for that IMA operation comes from.

what it all adds up to is... The use of IMA assist is generally only a MPG net benefit when the source of the IMA battery SoC was not a larger negative than the assist gives.

Of course a PHEV Insight is a much clearer case for the source of IMA battery power not having to come from gasoline at all... but that is not part of the OEM system... and requires some modding to make it happen.
 

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bciesq,

You say you also drive a '73 VW. I used to drive a '66 VW, so I know exactly where you're coming from with double-clutching/rev-matching shifting techniques.

As far as my driving style goes, I generally use all the gears Honda saw fit to provide - except that every once in a blue moon when I've "hammered it" in 1st & 2nd to 50+ mph, I'll shift straight to 5th (skipping 3rd and 4th).

But tell me this: Am I the only one who thinks that, by the standards of the old air-cooled-VW 1-2-3-4 shift pattern, the Insight gear shift pattern is more like 1½-3-4-5-5½ (that is, VERY tall in town, but much more close-ratio at highway speeds)? I like the Insight's highway gearing, but not the in-town ratios.
 

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hello again from stevedaniel. Got my destroyed transmission replaced today w/ a used one. Mr. Honda and Company knew what they were doing w/ the ratios. First gear is long, to get up significant speed w/ less rpms. Progressing smoothly and quickly through 2-3-4 to get to 5 is by design. Drive it like a diesel-- power curve there is usually 1500 rpm to a max of 2500 rpm. Get it into 5th ASAP, so that regen occurs when you let off the accelerator slightly, esp. when slowing routinely or descending a grade. "Engine compression braking" is less a factor than it would be in 4th (or less).

One of the hardest driving habits that I have had to re-learn is to use a prolonged light touch on the brake when slowing per traffic or descending a longer grade. "Riding the brake" was always a sin. In this car its engaging the regen capacity and not engaging friction braking. This really recharges the battery pack quickly! In other words, use the battery pack to assist, then recharge it. It defeats the purpose of having a battery pack if its not used!
 

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bciesq,

You say you also drive a '73 VW. I used to drive a '66 VW, so I know exactly where you're coming from with double-clutching/rev-matching shifting techniques.

As far as my driving style goes, I generally use all the gears Honda saw fit to provide - except that every once in a blue moon when I've "hammered it" in 1st & 2nd to 50+ mph, I'll shift straight to 5th (skipping 3rd and 4th).

But tell me this: Am I the only one who thinks that, by the standards of the old air-cooled-VW 1-2-3-4 shift pattern, the Insight gear shift pattern is more like 1½-3-4-5-5½ (that is, VERY tall in town, but much more close-ratio at highway speeds)? I like the Insight's highway gearing, but not the in-town ratios.
Switching back and forth from the Thing to the Insight is a challenge because lugging an aircooled VW motor leads to cooked heads, yet in order to get the best mileage around town in the Insight, you have to live on the edge of lugging the motor.

I've never heard the Insight's motor ping (of course these fancy modern engines have knock sensors), and I assume that as long as the shift indicators aren't screaming at me, I'm not doing any harm to the engine.

Others have noted that the Insight's gearing seems tall, and by ACVW standards it most certainly is. Then again, the Insight is a very different animal compared to the old VWs.

In my experience 4th gear is almost exclusively a low speed cruising gear (upper 20s to upper 30s). I rarely use it on the highway for acceleration. If I'm accelerating slowly, then I stay in 5th. If traffic or my mood dictates a brisker pace, then 3rd has really long legs. Hey, if I'm gonna punch it, might as well get some bang for my buck. Of course, Florida has no hills to speak of, so in different terrain 4th may be more useful.

In heavy downtown traffic, the challenge for me is to remember to get out of 2nd as quickly as possible. It's so easy to get distracted while avoiding octogenarians and tourists, and because the 2nd is so tall, I occasionally find myself cruising in the 20s when I should be in the 3rd or even 4th.
 

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For what it's worth, I have noticed an anti-node in the intake tract resonator tuning...

For those that may not have investigated this, our Insight has a rather large volume resonator, which helps boost the engine horsepower below 2000 rpm.

The maximum boosting of intake pressure occurs close to 1500 rpm or so, with a null point at 1900 rpm, then another peak at roughly 2300.

How does this information help with shifting?

When in traffic or out on old country roads, I tend to use a gear that is either slightly below or above the 2000 rpm dead zone. The volumetric efficiency of the engine is slightly better and a little more responsive, and potentially leads to better fuel efficiency. I use this technique when accelerating slowly.

Jim.
 

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For what it's worth, I have noticed an anti-node in the intake tract resonator tuning...

For those that may not have investigated this, our Insight has a rather large volume resonator, which helps boost the engine horsepower below 2000 rpm.

The maximum boosting of intake pressure occurs close to 1500 rpm or so, with a null point at 1900 rpm, then another peak at roughly 2300.

How does this information help with shifting?

When in traffic or out on old country roads, I tend to use a gear that is either slightly below or above the 2000 rpm dead zone. The volumetric efficiency of the engine is slightly better and a little more responsive, and potentially leads to better fuel efficiency. I use this technique when accelerating slowly.

Jim.
Thanks for the info. I refer to that as the granny zone and I had noticed that the car performed efficiently down low, but I didn't know why.
 
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