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-   -   how to smoothly shift back into gear from coasting in neutral (with engine running) (https://ecomodder.com/forum/showthread.php/how-smoothly-shift-back-into-gear-coasting-neutral-28545.html)

j12piprius 03-22-2014 01:22 AM

how to smoothly shift back into gear from coasting in neutral (with engine running)
 
My interpretation of instuctions on another thread are as follows:

1) coasting in neutral / foot not on clutch;

2a) push clutch all the way in;
b) let the clutch out part way (to spin up the motor);
c) then press it back down;

3) shift into the appropriate gear;

4) touch the throttle to bring up the engine speed / to match the transmission speed?

5) then release the clutch.

I presume that re-engage in #5 of instructions means release.

Is this all correct?

jedi_sol 03-22-2014 03:08 AM

Quote:

Originally Posted by johnlvs2run (Post 416400)
I have a few questions about these instructions and hope someone can help.



My interpretation of these instructions (#s don't match) is as follows.

1) coasting in neutral / foot not on clutch;

2a) push clutch all the way in;
b) let the clutch out part way (to spin up the motor);
c) then press it back down;

3) shift into the appropriate gear;

4) touch the throttle to bring up the engine speed / to match the transmission speed

5) then release the clutch.

I presume that re-engage in #5 of instructions means release.

Is this all correct?

Not quite. Here is how to bump start

While coasting with engine off and in neutral

1) clutch in
2) select 2 gears higher than you would normally be at any given speed
3) let off the clutch slowly until the engine fires on
4) then immediately step on the clutch again (this is to prevent the car from jerking)
5) select your normal gear at any given speed
6) blip the throttle to rev match
7) release clutch, then if you rev matched properly, the car should not jerk
8) continue driving

MetroMPG 03-22-2014 11:43 AM

In my car, 3a doesn't work well unless I quickly let the clutch out most of the way, and immediately depress it again when the engine spins up. It's a quick, fluid motion: up/down.

Letting it out slowly causes the car to slow down too much getting into the friction point, and it jerks when the engine yields and starts spinning.

jedi_sol 03-22-2014 12:27 PM

Quote:

Originally Posted by MetroMPG (Post 416440)
In my car, 3a doesn't work well unless I quickly let the clutch out most of the way, and immediately depress it again when the engine spins up. It's a quick, fluid motion: up/down.

Letting it out slowly causes the car to slow down too much getting into the friction point, and it jerks when the engine yields and starts spinning.

Yes true, but I am just assuming that since he is new ish to bump starting, he might not be familiar as to when his clutch starts to grab.

To poster, as you get better at bump starting, you can get to point where you can quickly "up/down" the clutch yet still be smooth in one quick motion .

jedi_sol 03-23-2014 04:14 PM

I think your clutch grab is really early, so yes you may be holding on the clutch for too long., thus losing speed .

Practice again without your shoes so you are more sensitive to when the clutch grabs.

Just keep practicing :)

MetroMPG 03-23-2014 06:09 PM

I once taught this to someone, and we found that talking about the friction point caused him to release the clutch far too slowly with the same result: he slipped the clutch against his stationary engine which dragged speed down a little each time.

We had much better results by learning where on the pedal travel the friction point is, and then quickly & smoothly releasing the pedal just past there and pushing it back in again. The whole engage/disengage action takes about half a second, and if done in a higher gear is smooth & drama-free.

It may all depend on the car, of course, but all the manuals I've driven have worked nicely this way.

MetroMPG 03-23-2014 07:44 PM

Maybe it's the car. But I'm thinking it's just taking too long. For me, it's a 1/2 second, up/down pedal movement to spin up the engine.

I don't try to consciously "play" the friction point (the way you do when you're starting up from a stop). I also don't consciously wait for the engine to start. It'll be running when the clutch is back down.

MetroMPG 03-23-2014 07:59 PM

Maybe recruit assistance from a forum member in your area?

It would require revealing where in the "western u.s." you're located, though. :)

jedi_sol 03-23-2014 08:58 PM

I'm in s. California if you happen to be in my area. I can help you out :)

jedi_sol 03-24-2014 01:08 AM

Quote:

Originally Posted by johnlvs2run (Post 416628)

The only thing that seems to work is to raise the throttle speed quite a bit before even starting to release the clutch, but surely there's a better way?

This statement makes it sound like your engine is actually ON while you are bump starting?

Assuming your engine was off, throttle input will do nothing...until the engine fires back on again.

Otherwise, based on your previous comment...

In other words, as soon as the pedal is moved from the floor, the speed drops immediately.

This sounds like your clutch simply grabs REALLY EARLY. Perhaps practice stepping off of the clutch for 1inch...then push it right back down immediately.


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