Shifting problems?

[Norkoastal]

Originally Posted by wheelhaus

The clunk is entirely normal. Most cars have softer tranny mounts that mask the clunk. This clunk is caused by the synchros forcing the input shaft to a sudden stop or sudden rpm. It's more noticeable wen stopped because you're not moving. You can sometimes feel it bump the car forward a hair because the input shaft's inertia is transferred into the gears. Norkoastal's "solution" simply allows some extra time for the input shaft to slow to a stop before engaging first. The gears are always and forever locked to rotate with the rear wheels (the clutch only affects the engine side). So when you disengage the clutch and roll to a stop, the input shaft is still spinning a bit. If you engage first sooner, you feel it clunk to a sudden stop; waiting a few seconds and it slows to a stop on its own. Either way, nothing is wrong.

[norkoastal] While I agree with your comments, I find them not accurate in scenarios where people are stuck at lights for 30 seconds to a minute.. Nothing is spinning in the drivetrain at those times.. I've been at a light for a minute and get the clunk.. Pressing the clutch for 4-5 seconds (basically timing the light) will usually keep you clunk/jerk free and offer a smooth glide into 1st gear from a stop..

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Selecting a gear has nothing to do with the flywheel, or engine speed once the clutch is disengaged. The synchros and the tranny oil are the only two things affecting shift quality between gears (unless something else is wrong). Slowing the shift movement into 2nd allows the synchros more time to match the internal speed of the input shaft. The slight "crunch" that is felt in 1st and 2nd is somewhat normal, you're feeling the synchros engage. 1st and 2nd use "triple cone" synchros that have more parts, and are designed to better hadle shifting at high rpm. at lower rpm, its more noticeable. The shifter in this car is a direct connection, not a vague cable actuated shifter to a transverse mounted tranny like many new owners are used to, which can mask things. Also, the tranny will shift smoother once it's up to temp, which could easily take 15-30 minutes depending on driving style and ambient temps.

[norkoastal] good comments.. My advice is to slow down the 1-2 shift waiting for the flyywheel to catch up, then slowly notch the gear into 2.. Using this process has given me the most consistent and notchy/jerk free experience. Shifting too fast introduces "Bite" and syncho catching.
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Agreed here, if you're getting a sudden jerk when trying to accelerate from a dead stop, don't release the clutch so suddenly, or just rev to a higher rpm and let it slip just a bit. Shifting at 3k is fine for putting through traffic, but it's far too limp if you're trying to merge onto the freeway. If you're accelerating hard through the gears, let the engine rev as high as you want and shift quickly, in this case a surge forward is normal due to engine rpm (and the flywheel inertia as Norkoastal mentioned above). It's perfectly fine to let it slip some in 1st if you're trying to get moving as quick as possible, but you don't want to be excessive to the point you can smell it. Hard launches require some clutch slip. Normal traffic requires minimal clutch slip from a stop, and none when rowing between gears.

Great info Haus!!

[wheelhaus]

Originally Posted by norkoastal

While I agree with your comments, I find them not accurate in scenarios where people are stuck at lights for 30 seconds to a minute.. Nothing is spinning in the drivetrain at those times.. I've been at a light for a minute and get the clunk.. Pressing the clutch for 4-5 seconds (basically timing the light) will usually keep you clunk/jerk free and offer a smooth glide into 1st gear from a stop..

You're experiencing exactly what I described.
I suspect you do the same thing I do when stopped at a light, which is to shift to neutral and release the clutch.

So, the gears are not moving, but the input shaft is spinning inside them because the clutch is engaged. When you disengage the clutch and select 1st, the synchro quickly matches the speed difference and causes the input shaft to stop, which causes the clunk. It doesn't matter how long you're stopped, if the clutch is engaged, then the input shaft is turning.

If you go back to neutral and release the clutch, the input shaft is again tied to the engine so it spins at engine rpm again. You should be able to repeat this and get the clunk every time without ever moving forward.

[forzajuve]

You are never supposed to shift into 1st gear unless you are going MAYBE 5mph or lower. The only time you should shift into first is when you are at a complete stop and need to move forward.

[Gords_zenith]

Originally Posted by forzajuve

You are never supposed to shift into 1st gear unless you are going MAYBE 5mph or lower. The only time you should shift into first is when you are at a complete stop and need to move forward.

That was true only to old cars that didn't have 1st gear syncros.

I skip shift but row the gears normally but don't let the clutch out between each one, and then engage the gear I wanted.

[Chinadian]

For those who have shifting issues i would recommend the clutch adjustment mod and see if it improves. I had lots of shifting issues of non-smoothness and gassing too early but after I did the clutch adjustment my shifting has been alot more smooth.

[racer_tom]

Originally Posted by Chinadian

For those who have shifting issues i would recommend the clutch adjustment mod and see if it improves. I had lots of shifting issues of non-smoothness and gassing too early but after I did the clutch adjustment my shifting has been alot more smooth.

What clutch adjustment are you referring to? Can you please point to how this is accomplished or what is done? I'm very interested in trying this.

Just found this thread :: http://www.ft86club.com/forums/showt...tch+adjustment
Were you referring to this engagement point adjustment>

[Chinadian]

Originally Posted by racer_tom

What clutch adjustment are you referring to? Can you please point to how this is accomplished or what is done? I'm very interested in trying this.

Just found this thread :: http://www.ft86club.com/forums/showt...tch+adjustment
Were you referring to this engagement point adjustment>

Yes

[Skurj]

Sounds exactly like my car... they say its the norm!

[eSOLOR]

So my BRZ is my first manual car too. I had driven manual before I got it but I'm no way perfect at it. When I put the car into first and second gear, it sometimes makes a "crunch" sound. I feel like I'm shifting wrong and grinding on something. Are you guys saying that's normal for this car?

[448hpsti]

Did u adjust your clutch at all?

[eSOLOR]

No I did not but that's something I plan on doing in the future since I feel the grabbing point is a bit too high. Does that affect it?