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I really have to push hard upshifting into 2nd and 3rd on a launch when I rev to redline 7k rpm
It's no effort upshifting to 5k rpm, little more at 6k rpm.
It's easy pulling out of gear, so I think the clutch must be fully disengaged.
Installed southbend Kevlar clutch and PP, and put new royal purple synchromax in 10k miles ago.
Also put a new clutch slave cylinder and clutch oil line.

It wasn't this hard to shift after I installed my supercharger 15k miles ago, don't really know when it started getting worse. I don't redline shift a lot, not really need it with the supercharger.

Oh I have had a Rogue short shifter and dssr for many years now; more effort to shift and it pops into gear, but it never took this much force. It's not grinding though.

Any thoughts?
 

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Well, mine got much better after changing the oil in the gearbox. If not already done, you should start here (easy and cheapest fix). If that won't cut it, then it can be your shift linkage og worst of all, your synchro mesh in the gearbox that needs renewal. When they wear down, the small alignment/synchro splines get further and further away for their optimum engagement point, which will lead to a growing greater force required for engaging the gear. Have changed a few of these in other gearboxes, you need to take the gearbox totally apart, so while you're at it, throw in new bearings and seals, the price and little time needed here is nothing compared to the synchromesh and time taken to take the gearbox out and take it apart :)
... And as always, I don't think 2nd gear will be completely without trouble, as far as I understand, 2nd is always harsh to change to with low revs and cold gearbox...
 

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That's quite an unusual problem you have there. There are tons of threads about baulky second gear shifts during normal driving, especially with cold oil, but I don't recall any specific to high rpm/high load shifts. It sounds like the synchromesh cones are worn for those gears but I'm not sure why this would only happening at high rpm. I thought worn cones would cause a problem right through the rev range, in fact maybe more so at lower rpm where gearbox inertia is less.

Is there any chance the clutch you have is still slightly engaged at high rpm? It might be worth calling the manufacturer.

If it is an internal gearbox problem, the problem is you can't get parts so a rebuild can't be done. So it's either a used gearbox (seems that a 540 one fits, except for cruise control) or a remanufactured one from BMW (big $$$).
 

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I also have RE kit and it's difficult to up shift, lots of times I couldn't get into 2nd at higher rpm.
 
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