Hard to Shift at High RPM's
 

I have a problem with shifting quickly/smoothly at RPM's above 5-6k. It's even noticeable around 4500 or so, just not as bad.

I have an Exedy clutch (nothing much above stock feel), which grabs and disengages like it should. So I don't think it is the clutch.

Also, the tranny shifts pretty smooth. I never get any grinds except 5th gear, I just feel like I'm getting locked out in higher RPM's.

Does this sound like shifter bushings? Should I replace all of them? Engine and in the shifter bracket?

Please let me know what this could be! Any help is greatly appreciated. Thanks

I had same problems and I change out the shifter bushing and front motor mount & a engals engine damper. That fix problems from lock outs {thumbup}

I've already got polyurethane engine/tranny mounts all around, so I will try the bushings and damper!

Thank you!

Update, it looks like the under hood bushings have already been replaced by Buschur solid bushings.

Now I am really at a loss, anyone have any ideas? :/

I vote for throw-out bearing.

Have you attempted to adjust your clutch pedal a bit higher?

http://www.evomoto.com/tech_articles..._article_id=28

Might want to check your TOB as well.

The pedal adjustment is interesting. Is it possible that's what it could be? I ask because I never have problems going into gears at low RPMs.

Also, could somebody explain what the TOB could be doing to create this problem? I just want to understand it.

Update: Adjusting the clutch pedal seemed to help a bit. I was thinking, could it be that the clutch system should be bled? Maybe some air in the lines? Or fluid is to old?

Also, is it a common problem for the clutch to NOT disengage fully above a certain RPM?

The throwout-bearing is the bearing that is located on the shifter-fork. When you go to push in the clutch pedal to engage or dis-enguage the clutch the center of it constantly spins.

If its worn or faulty or not properly lubricated when installed youll hear a squeeky noise a hard noise like something is rubbing which is followed by hard shifting becasue the throw-out bearing isnt doing its job which can lead to messing up your tranmission and clutch altogether. Take some time to look at this video http://www.youtube.com/watch?v=6BaEC...eature=related look at the red part thats on the clutch thats a throw-out bearing if it goes bad pay close attention on sequence 0:55 that red circle part thats on the center of the spline-shaft is the throwout bearing. The red thing that looks like a rod thats the shifterfork which is attached to the clutch pedal which is maniplated for the master cylinder connected to the slave cylinder which does the work for the master cylinder.

That's all great info. Thank you. I understand how the clutch system works for the most part, just was confused as to why, at high RPM it's hard to shift and not at low RPM.

So far the car seems a bit better because of the adjustment, but the clutch won't fully grab until the pedal is almost at the end of travel, is that okay?

Do you launch your car often? or goto the drags? The exedys can warp the pressure plate pretty easily if you overheat it by slipping to much on a launch. This would be a symptom of a warped pressure plate.

Think back to when the issue started, if your answer is 'at the drag strip', you now know whats wrong :)

On the plus side its probably only the clutch that needs to be fixed at this point but even though it doesn't feel like it a lower rpms, if the pressure plate is warped it will be placing extra wear on your transmission, especially the synchros.

Are you getting locked out of any gear at high rpm? or just 4th? (4th is single synchro and usually the first to experience lockout problems)

I'd put my money on the clutch and/or pressure plate going bad. I used to have an Exedy Stage 2 single plate in my car and was getting lockout above 6500 before it really started slipping and I had to have it replaced.

I have an Exedy Tripple, shifter bushings and motor mounts. I tried shifting today at 8500 rpms, no problem, smooth as butter. You might need a better clutch for your power level.

I just bought the evo, the woman who had it before me claimed to "race" it. Sounds like I have found the problem.

I plan to be at or around 350-400hp, so nothing to crazy. Clutch recommendations?

It needs an adjustment it shouldnt grab when its almost at the top about to let go. It should grab when its slighltly just before halfway up. Too much down to the floor youll mess up the throwout bearing and drivetrain because its not enguaging fully.

Too much up top will cause shock and warp from you riding on it or youll constantly stall messing up somethign else. I think you need to do an adjustment of the clutch pedal engagement point. Find someone who can do it for you to where you feel comfortable with so that it will operate properly. I have not done this yet but im sure I will.