C2S 7MT - 1st to 2nd shift near redline - problem?
03-11-2015, 02:27 PM
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C2S 7MT - 1st to 2nd shift near redline - problem?
Hi All,
I have a 2014 C2S 7MT without sport chrono and noticed that under hard acceleration and shifting from 1st to 2nd near redline (say above 7000rpm) I am feeling a binding/slight grinding during the shift. This has happened at least 4 times and at least twice I was bounced out of the gate, like a missed shift. This was not a full "gear grind" where a new driver would grind gears, (Although I've done that once or twice
)
I'll be the first to admit that I'm not a pro driver and all of this may be due to my clutch/shift technique. This only happens during 1st to 2nd and under wide open throttle. If I shift at say 6700 rpm I do not have this issue. Also 2nd to 3rd doesn't have the same issue.
My thoughts are I may be hitting fuel cut-off, or I may just need to shift a bit slower to allow the syncromesh to work better. The engine revs so fast from 6000 to 7400 I may just need grab the gear earlier. I've never had this problem in my 2003 M3. That car slows considerably above 7000rpm which allows plenty of time to grab the next gear.
Just wondering if anyone else has noticed this?
I have a 2014 C2S 7MT without sport chrono and noticed that under hard acceleration and shifting from 1st to 2nd near redline (say above 7000rpm) I am feeling a binding/slight grinding during the shift. This has happened at least 4 times and at least twice I was bounced out of the gate, like a missed shift. This was not a full "gear grind" where a new driver would grind gears, (Although I've done that once or twice
)I'll be the first to admit that I'm not a pro driver and all of this may be due to my clutch/shift technique. This only happens during 1st to 2nd and under wide open throttle. If I shift at say 6700 rpm I do not have this issue. Also 2nd to 3rd doesn't have the same issue.
My thoughts are I may be hitting fuel cut-off, or I may just need to shift a bit slower to allow the syncromesh to work better. The engine revs so fast from 6000 to 7400 I may just need grab the gear earlier. I've never had this problem in my 2003 M3. That car slows considerably above 7000rpm which allows plenty of time to grab the next gear.
Just wondering if anyone else has noticed this?
03-11-2015, 03:15 PM
#2
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what sort of mileage on the car, and did this happen while the transmission was cold?
03-11-2015, 03:25 PM
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I think you need to grab 2nd sooner.
You can wring out the other gears/shifts. 1 to 2 comes up very fast at WOT.
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You can wring out the other gears/shifts. 1 to 2 comes up very fast at WOT.
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03-11-2015, 03:27 PM
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you really have to hope its not the synchros wearing ... you might think about a tranny lube change...
03-11-2015, 03:56 PM
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The engine/trans oil was warmed to at least 197F. I never go to redline or WOT when the car is cold, only after 10-15 mile warm up. Mileage just turned 4000 yesterday, so car is relatively new.
I'm thinking I probably need to shift earlier than 7K in going from 1st to 2nd to mitigate this issue. 2nd to 3rd never been a problem even at 7400rpm as it approaches the redline slower than in 1st gear.
I'm thinking I probably need to shift earlier than 7K in going from 1st to 2nd to mitigate this issue. 2nd to 3rd never been a problem even at 7400rpm as it approaches the redline slower than in 1st gear.
03-11-2015, 03:58 PM
#6
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May also be a clutch issue related with your seating position. Always make sure that your seat position allows you to depress the clutch to its fullest. If not It can affect the gate.
03-11-2015, 03:59 PM
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And make sure your seating position allows you to get that clutch in fully.
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03-11-2015, 04:13 PM
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Good point about the seating position. I may be not fully depressing the clutch all the way in the interest of trying to shift faster/better etc. That could explain why it only happens occasionally, just human error at that point. I have no problem blaming my driving style for inconsistencies in the cars performance...
If only they made a transmission that fully depressed the clutch for you and all you had to do was move the gear lever and modulate the throttle to affect a smooth sporty gear change?
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
If only they made a transmission that fully depressed the clutch for you and all you had to do was move the gear lever and modulate the throttle to affect a smooth sporty gear change?
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
7mt
03-11-2015, 04:29 PM
#10
Drifting
If only they made a transmission that fully depressed the clutch for you and all you had to do was move the gear lever and modulate the throttle to affect a smooth sporty gear change?
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
Yeah, maybe while they're at it they'll make a sportscar that runs on electricity and you just plug it in to the wall.
03-11-2015, 04:31 PM
#11
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03-11-2015, 05:10 PM
#12
Drifting
03-11-2015, 05:24 PM
#13
Instructor
Hi,
I have had this happen a couple of times too. I find that 1st to 2nd when the car is cold that the shift is very balky going into 2nd. I'm a little leery of the 2nd gear synchro to be honest, and at least one of the initial 991 road tests wondered how long the 2nd gear synchro would last. Redline in first does come up really quickly and I think I may have been guilty of not depressing the clutch all the way in. I haven't ground the gears but I have had some less than ideal shifts into 2nd. I try to pay more attention to technique now that I am more used to the car.
I have had this happen a couple of times too. I find that 1st to 2nd when the car is cold that the shift is very balky going into 2nd. I'm a little leery of the 2nd gear synchro to be honest, and at least one of the initial 991 road tests wondered how long the 2nd gear synchro would last. Redline in first does come up really quickly and I think I may have been guilty of not depressing the clutch all the way in. I haven't ground the gears but I have had some less than ideal shifts into 2nd. I try to pay more attention to technique now that I am more used to the car.
03-11-2015, 05:53 PM
#14
What if you made a mistake with turning, braking, or throttle input?
Wouldn't it be wonderful if there was a way to take all human error out of driving? That way you could get a real "drivers car" and tell people how much you enjoy driving while you sit there watching videos on you can enjoy all the perfectly executed shifts, braking, turning, and throttle being down for you by a computer. Better yet, not slow the car down with your weight and just side in an air conditioned room as the car drives without you.
Wouldn't it be wonderful if there was a way to take all human error out of driving? That way you could get a real "drivers car" and tell people how much you enjoy driving while you sit there watching videos on you can enjoy all the perfectly executed shifts, braking, turning, and throttle being down for you by a computer. Better yet, not slow the car down with your weight and just side in an air conditioned room as the car drives without you.
Good point about the seating position. I may be not fully depressing the clutch all the way in the interest of trying to shift faster/better etc. That could explain why it only happens occasionally, just human error at that point. I have no problem blaming my driving style for inconsistencies in the cars performance...
If only they made a transmission that fully depressed the clutch for you and all you had to do was move the gear lever and modulate the throttle to affect a smooth sporty gear change?
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
If only they made a transmission that fully depressed the clutch for you and all you had to do was move the gear lever and modulate the throttle to affect a smooth sporty gear change?
Better yet forget the gear pattern, just have some kind of lever or paddle you could tap to move the gear up or down to correct ratio! Then you could focus on turning, braking and throttle input only...
If only some company could develop such a system...
03-11-2015, 06:54 PM
#15
Banned
Seriously, even with all the driving aides we have today. Nothing can prevent a car from going off the road. When entering a turn too hot. Surely they are working on it.