I recall an issue with another member where the shift linkage popped off the shifter in one case.
Now I'm not familiar with the micra's manual transmission enough to say 100% its this or that. But sometimes it can be a weak clutch cylinder (master or slave) not applying enough pressure to separate or apply the clutch, that can sometimes lead to a hard engagement and release of the gear selected.
Most syncromesh transmissions have a brass "syncro ring" that can wear out or fail, and that can affect engagement as its purpose is to guide the gears together- but typically its usually one affected gear, and normally only when enaging the gear, so I dont think thats it.
Some clutches can be adjusted. My mazda has a simple piston that could be adjusted in and out by a nut and threaded rod. Im not sure about the micra, but it could be out of adjustment and not fully engaging or disengaging the clutch, leading to harsh engagements and disengagements. All clutches do wear to a certain degree and need a little adjustment to keep them in check. It might be just a quick clutch adjustment is all that is needed.
Also a lot of people dont understand that while you can shift without using a clutch, this practice isnt reccomended. Its hard on the syncrhos. Also rev matching can greatly increase the lifespan of the clutch assembly. The clutch is designed to separate the engine and transmission to make shifting easier, not to make up for a difference in rotation. So if you happen to be one of those people that push the clutch in and let the engine rev up then upshift- dont do that. Likewise, dont do the opposite and let the revs fall too much, that can also cause premature wearing of the clutch.
Some people cite the 3-5 rule. This meaning for each gear you change, expect a 3-500 rpm difference between gears:
1st 1500rpm *clutch in, lower engine rpm* 1200 rpm *shift, clutch out*
2nd 1500rpm *clutch in, lower engine rpm* 1200 rpm *shift, clutch out*
etc.. Of course, each individual ratio is going to make the rule a little off but 300-500rpm is a good range to start, and you can fine tune it when you learn the car.
Downshifting (or slowing down) would be...
2nd 1500rpm *clutch in, rev engine* 1800 rpm *shift, release clutch*
1st 1500rpm *clutch in, rev engine* 1800 rpm *shift, release clutch*
When you press the clutch in, and match the engine speed to the speed that the transmission is rotating on, you will have nicer shifts and less wear on components. Really the clutch is for starting and stopping, and taking up the minor differences between gear changes and seperates the engine from the transmission to make it easier to shift.
When I drive tractor, there is an old technique that is sometimes passed along called progressive shifting. As you all probably know, you dont have to shift at 1800 and 1200 every time. Its a dynamic range. If you shift at 5000rpm, you might end up being at 3000 rpm for your next shift depending on the ratio. You can play with it. the 3-5 rule is just a rough guideline. Now depending on who you talk to in the truckstop, progressive shifting is sometimes thought to be one of the more fuel efficient ways to shift. Kinda looks like this:
Now of course it doesnt work 100% like that. But basically you increase your bottom rev by 100rpm each time until you reach maxximum power. Ive tried it. I dont think it saves fuel. But worth a shot none the less.
Last edited by Howie; 02-22-2016 at 11:05 AM.
View my fuel log 2015 Micra S automatic: 7.9 L/100 km ... 35.7 mpg (Imp) ... 12.6 km/L ... 29.7 mpg (US) ...