MINI2

MiniDoug · Mar 17th, 2004, 03:06 PM

I have a July 03 CVT and when slowing down for a light, it seems to change down say in the last five yards with an unpleasant lurch. Rather like putting a manual into first and dropping the clutch. Result head swings forward a la whiplash. This doesn't happen if you feather the brakes and anticipate the slowing down.

I feel the transmission should be a lot smoother and more progressive when slowing. Has anyone had V36 software installed and does this improve the behaviour of the transmission? It is also not very smooth when accelerating hard. If you take the throttle to the detente and the revs to 5000 then acceleration is fast and smooth. If you mash the loud pedal the revs jump to 6000 and when the upper speed for a given gear is achieved the tranny changes up with a drop in revs and again a lurch.

Any comments or opinions would be appreciated!

Thanks

nonsequitur · Mar 18th, 2004, 04:04 AM

Two situations, very different of course.

The acceleration observations seem to be the normal differences between the native CVT-mode (steady revs at 5500rpm, smooth acceleration) and AT-mode (computer managed "shifting" behavior, upshift at 6000rpm with a drop down to about 5300rpm for the next "gear") where a lurch occurs as the Van Doorne belt is repositioned to the next fixed ratio.

The other is something that seems to be also showing for me as v36.0 works into sync with our driving. I'm fairly certain that it is the gearbox switching into Low which is used for Setting-off (Launch). As the car slows in D or SD and revs drop to about 1400rpm with the brake engaged, the belt is positioned onto the fully open Primary pully (Variator) ... with a bit of a slap. In Steptronic, that same thing happens at 1400rpm nearly exactly. So this sensation, which may not be as smooth as it was under previous software versions, is the gearbox preparing to come under acceleration from stop.

Check this out and let us know if you agree. Anyone else?

stellablade · Mar 18th, 2004, 11:30 AM

That happens in my manual Cooper. I've got used to it now and tend to either put it into neutral or press the clutch.

Quote: Originally Posted by MiniDoug

I have a July 03 CVT and when slowing down for a light, it seems to change down say in the last five yards with an unpleasant lurch. Rather like putting a manual into first and dropping the clutch. Result head swings forward a la whiplash. This doesn't happen if you feather the brakes and anticipate the slowing down.

Thanks

UNeeUn_Jack · Mar 24th, 2004, 01:10 PM

Pushing the CVT gear lever into neutral just before you stop is the best way I've found of eliminating this uncomfortable hiccup. This also allows the revs to drop a little more when stationary (and so save gas) - I'm assuming that this is because when stopped in D, the engine is pulling slightly against the brakes.

Mar 17th, 2004, 03:06 PM	#1
MiniDoug MINI2 regular Join Date: Dec 2003 Location: East London Local Time: 08:03 PM Posts: 199 Offline	Lurching when coming to a halt? I have a July 03 CVT and when slowing down for a light, it seems to change down say in the last five yards with an unpleasant lurch. Rather like putting a manual into first and dropping the clutch. Result head swings forward a la whiplash. This doesn't happen if you feather the brakes and anticipate the slowing down. I feel the transmission should be a lot smoother and more progressive when slowing. Has anyone had V36 software installed and does this improve the behaviour of the transmission? It is also not very smooth when accelerating hard. If you take the throttle to the detente and the revs to 5000 then acceleration is fast and smooth. If you mash the loud pedal the revs jump to 6000 and when the upper speed for a given gear is achieved the tranny changes up with a drop in revs and again a lurch. Any comments or opinions would be appreciated! Thanks

Mar 18th, 2004, 04:04 AM	#2 (permalink)
nonsequitur MINI2 Master My Classifieds Join Date: Nov 2002 Location: Seattle area, WA Local Time: 11:03 AM Posts: 1,471 Offline	Two situations, very different of course. The acceleration observations seem to be the normal differences between the native CVT-mode (steady revs at 5500rpm, smooth acceleration) and AT-mode (computer managed "shifting" behavior, upshift at 6000rpm with a drop down to about 5300rpm for the next "gear") where a lurch occurs as the Van Doorne belt is repositioned to the next fixed ratio. The other is something that seems to be also showing for me as v36.0 works into sync with our driving. I'm fairly certain that it is the gearbox switching into Low which is used for Setting-off (Launch). As the car slows in D or SD and revs drop to about 1400rpm with the brake engaged, the belt is positioned onto the fully open Primary pully (Variator) ... with a bit of a slap. In Steptronic, that same thing happens at 1400rpm nearly exactly. So this sensation, which may not be as smooth as it was under previous software versions, is the gearbox preparing to come under acceleration from stop. Check this out and let us know if you agree. Anyone else? '02 MINI Cooper CVT(6/12/02; Indi Blue/Black, R-81 7-hole 15x5.5" or NZO 16x6.5") '67 Austin Cooper S (6/26/67; Tartan Red/Black, 10x4.5")

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Mar 18th, 2004, 11:30 AM	#3 (permalink)
stellablade MINI2 Senior Join Date: Jun 2002 Location: Sheffield Local Time: 08:03 PM Posts: 412 Offline	That happens in my manual Cooper. I've got used to it now and tend to either put it into neutral or press the clutch. Quote: Originally Posted by MiniDoug I have a July 03 CVT and when slowing down for a light, it seems to change down say in the last five yards with an unpleasant lurch. Rather like putting a manual into first and dropping the clutch. Result head swings forward a la whiplash. This doesn't happen if you feather the brakes and anticipate the slowing down. Thanks

Mar 24th, 2004, 01:10 PM	#4 (permalink)
UNeeUn_Jack MINI2 Newbie Join Date: Nov 2003 Location: Toronto Local Time: 02:03 PM Posts: 13 Offline	Pushing the CVT gear lever into neutral just before you stop is the best way I've found of eliminating this uncomfortable hiccup. This also allows the revs to drop a little more when stationary (and so save gas) - I'm assuming that this is because when stopped in D, the engine is pulling slightly against the brakes.

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