I do this out of habit in exactly the same circumstances you describe, car rolling at walking pace and engaging first.
Dipping the clutch, into neutral, lift clutch, dip clutch again and engage first, slips in easily and smoothly.
If I don't do this, and just kept the clutch pedal pressed down, my new Mondeo (1 year / 12,000 miles old) AND my previous Passat would require VERY firm pressure to get into first gear.
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Not something I've done for some time, but I used to have an old Landie with no sync on 1st. Learning how to manage the gearbox on that was useful in that when the clutch cable on a Renault 19 went I managed to get it 20 miles home without any major drama.
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Am I right in thinking first gear is a usually a straight cut gear, and the rest (excluding reverse) are hellically cut gears? Hellically cut gears will merge together much more easily than straight cut.
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I think all gearboxes (since the 80s, at least) have helically cut forward gears, including 1st, and straight-cut reverse. Hence the pronounced gearbox whine when moving backwards ...
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>>will merge together much more easily than straight cut.
You're getting a bit mixed up DD.
In the forward gears, when you move the gearlever, you aren't actually moving any gears into or out of mesh - the forward gears run in constant mesh. What you are doing is locking and unlocking free-running gears from the shaft that runs on the same axis.
The synchromesh acts as a brake between the shaft and the free running gear you're trying to lock, forcing them to turn at the same speed, prior to the final egagement of the dog teeth that actually lock the gear to the sgaft, and transmit the torque from shaft to gear (or vica versa).
So, in terms of ease of selection of the forward gears, the type of cut on the gear, straight spur, helical, or whatever, doesn't matter. It's the details of the synchromesh which determine what you actually feel at the gearlever.
Reverse is an odd one, and on modern gearboxes can even be engaged with synchromesh in the manner I have described. On older gearboxes, it was more common to use a straight cut reverse gear which did actually slide along the shaft into engagement, without any synchromesh - after all, there are very few good reasons to want to engage reverse while you're moving.
Having no synchromesh on reverse was a very handy diagnostic technique - if a clutch was dragging, you could tell by trying to engage reverse. If, after pressing the clutch fully, and waiting a few seconds for the shafts to stop, if it crunched, you knew the clutch wasn't clearing properly, or the spigot bearing was seizing. Now, with the nonsense of synchro on reverse, such a diagnosis would be more tricky.
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I think posters are talking about two rather different phenomena:
1) is the baulking you can sometimes get when engaging 1st from rest, because the splines on the first gear cone just happen to be in end-on position. Old cars, and some new ones, can do this. Letting the clutch up briefly in neutral lets them reposition.
2) is true double declutching, either because that gear never had syncromesh, or it has worn out. This would be used to engage the gear while the car is moving.
Incidentally the old LandRovers lacked syncromesh on both 1st and 2nd gears. The technique for changing up, as opposed to down, is slightly different.
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I had an elderly uncle who never stopped double-declutching. A good thing too, he could still drive a manual when his arthritis was so bad most people would have had to have driven an automatic.
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I dont "double declutch" on changing down, I "heel and toe"*.
That is I brake and blip the throttle at the same time when the clutch is depressed just once during the change down. I do this much less now because the VW 105pd unit has enough low down torque to enable pull away in 2nd. from walking pace.
*why is it called heel and toe? the brake is applied with the ball of the foot and the throttle blipped with the side of the foot. The heel never comes into it.
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*why is it called heel and toe?
Not all cars have, or had, the brake and accelerator pedals close together and more or less level with each other, permitting the AE method with the two sides of the right foot. If the distance, or difference in level, is too great for that method, then the same technique can be used with the toe on the brake pedal and the heel operating the accelerator. It is very much easier in some cars than others.
I still blip the throttle when downchanging without double declutching, but it's hardly necessary with these suave modern cars and many instruction books seem to advise against it. Actual double declutching is only needed when the synchro has gone on the gear being changed into. If the synchro is so knackered that even a slow gearchange won't give it time to work, it can be necessary to double declutch on upchanges as well as downchanges. My Light 15 Citroen was like that. The three-speed gearbox, meaning big gaps between the gears, made it even more necessary.
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Although I greatly enjoyed Jack Kerouac's novel On The Road when I first read it over 50 years ago (it was fairly new then), Kerouac annoyed me by making his speedhead gung-ho driver character Dean Moriarty babble 'doubledy-clutch, doubledy-clutch' as he hurtled about America in borrowed or stolen Cadillacs and the like.
It annoyed me because it showed Kerouac didn't know the meaning of the expression and hadn't bothered to find out. Of course Neal Cassady, the real person on whom the Moriarty character was based, would have known. Almost everyone in the novel was based on a real individual. In fact it was hardly a novel at all, more like a chunk of undisciplined autobiography (still worth a read though for those who haven't read it).
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One of my early cars, an MG Midget as I recall, had a very worn gearbox and smooth changes required a double declutch. It took me years to break the habit of doing it as a matter of course in later cars. Clutchless gearchanges were another way of getting around the problem.
Now, I sometimes do one or the other just for the distraction value, can't really say why. Other idle timewasting habits include trying to avoid running over catseyes when changing lanes on motorways. Seeing how far I can go in miles and time without using the brakes or trying not to have to let the car stop at all for as long/far as possible in a long journey. Not slowing down or breaking pace for corners and roundabouts ( provided there is no one else about ) is another source of amusement.
This all of course goes by the way if there's something good on the radio.
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Humph, all worthwile amusing driving tactics that I employ, with the addition of hitting clipping points on bends, exiting same on accelearation. Add to that finding out how far round the bend i can see even if that means - shock horror - crossing the unbroken white line if safe to do so.
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Oh dear, I'm afraid I might do those too while we are having a small confess. Let's hope that one or both of us would be be sharp enough to react appropriately were we to be doing one or more of them while travelling on the same road from opposite directions ! If not, at least it would be a small comfort to know that it had resulted in an elegant and precise sort of impact......
;-)
Edited by Humph Backbridge on 14/04/2009 at 18:35
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Lud - you had a light 15? ALA traction avant?
me doffs his cap
My dream classic - in black. (mind somehow only someone in jackboots and a wermacht uniform of officer rank could climb out the suicide doors with elegance and style, ladies could not do it with any form of modesty.)
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I do it in cars out of mechanical sympathy and simply because it's satisfying, I have to do it on the bike as they don't have syncromesh so I'm used to matching revs with roadspeed
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You are a man of taste (sometimes) AE.
I posted something about my Avant Voleur here once, or I think I did. It was a matt desert sand coloured 1948 'small boot' (therefore correct looking) left-hooker with twin carbs and one of those four-spoke spring steering wheels. Bought it in 1962 from two Aussie girls in West Kensington for 60 quid, loved it dearly, trashed it in about three months. I could post my detailed memoir of it if anyone is interested, but I think it's all been on here before.
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My vintage car has no syncromesh so you have to double declutch down changes and time the engagement of first from a standstill. Clutch pressed for too long and it just won't go into gear at all.
It's different, but once you get into the swing of driving it, not hard.
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I usually find that cars dont go into first gear is because people have baulked them into this gear while coming up to junctions at far too fast a speed and they dont want to just keep the car rolling in second gear and drive off slower but smoothly.
(one of my pet hates after shortss is customers ramming the gearnob into first when its totally inappropiate
(no offence OP)
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... all been on here before.
Yes, thought so: First Wheels, 7 May 2007, one appreciative reply from eProf, only 80 readers.
Edited by Lud on 15/04/2009 at 17:02
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I am trying to put the car into 1st when it is almost stationary - traffic light turns green just as I am about to come to a halt.
OK, you said "almost stationary" but it drives me bonkers that the girls in my house all try to ram the car into first if it drops below about 15MPH!!
Most cars will pick up fine in 2nd gear as long as it's actually rolling, and you don't get the resistance selecting 2nd that you do with 1st.
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good man BIILL p a man after my own heart
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Bellboy - it's dog engagement. Unless the gear stops with about 2 of 360 degrees rotation it won't to into gear. So the only safe way is to select the gear, just as the shaft comes to a halt.
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sorry me thick no understandy
are you saying first gear is designed to be put in as the car is rolling
or not?
see ive always seen first gear as a gear to get the car rolling not to whack it into when the vehicle is moving
many is the time i dont use 3rd either for the same reason,or fourth if im going down a hill
thanks
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I,too,cannot see why there would be a need to engage first when slowing for lights or junction.Either stop then engage to pull off,or use second if you find you do not need to stop.Incidentally,when I had low gear engagement problems it transpired that the spigot bearing(needle roller)had collapsed and was allowing the input shaft to flap about.I had much fun removing the remaining cage
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cannot see why there would be a need to engage first when slowing for lights or junction
A lot of people can't see it, but I can. It's usually on a steep uphill junction from your point of view, where you may have to stop but may not.
We have all at some time or another crunched the lever into first on the move (that's why everyone seems so indignant about it: because they have done it themselves often enough to get annoyed). But of course one doesn't have to do that. In fact changing into first on the move is just about the only occasion one has to double declutch these days.
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Bell boy
Dog engagement is like two face to face castle nuts, if one is in the right orientation compared to the other, they mesh, otherwise they don't. As one is connected to the back wheel and the other is on a shaft that is connected to the engine, you need to get them aligned, or as is much more likely moving relativly slowly compared to each other so that a bit of pressure will get them to mate.
Would be simple to understand if I was able to show you.
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I remember baulking was often a problem on older gearboxes that didn't have synchromesh on first, just simple dog engagement but no cone clutch, but I thought now that all gearboxes are all-synchromesh first was no different from any other?
So what's this about crashing into first gear while still moving - even my 1993 Volvo of antiquated 1977 design has a perfectly adequate synchromesh on first. If I really wanted to I could change into first at 20 mph without any problem, and might do so if approaching a very steep hill with a laden trailer, rather than risk bogging down in second.
BTW Heel and toeing was much easier with an organ pedal accelerator - do they still exist?
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If you mean a pedal attached to the floor, then yes, our VW Touran has this. I hate it as stones can get trapped under it, which is flaming dangerous.
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My first car was a 1929 Riley Monaco with no syncromesh - by design. I had to double declutch to change gear.
Never did it again : it's a pia.
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