My car arrived at the dealership late yesterday and didn't make it through PDI but I went to take a look anyway. I started it up and expected butter smoothness from the engine but there was actually quite a bit of vibration feedback through the shifter and inside the car. Is this normal? Is it something to do with not being PDI'd (blocks in place, etc)? I have just heard of the legendary smoothness of this motor and honestly the v6 in my Jetta idles far smoother then what I experienced last night. I am going out today to check it out after PDI but thought the "rotorheads" would have some insight.

Well given that at this point only about ten people here actually know... :D :D

I have mine since Monday and there is some vibration at idle, you notice it in the shifter, but otherwise it's pretty smooth.

Yes it does. Even in neutral you can see the shifter vibrate. As you shift the gears it vibrates. I guess this is normal for a rotatary.

One thing I notice is the clutch catches very high. Almost have to take your foot off before it does. Not sure if this is normal. Wonder if can be adjusted to catch at halfway.

Originally posted by Wolfer
One thing I notice is the clutch catches very high. Almost have to take your foot off before it does. Not sure if this is normal. Wonder if can be adjusted to catch at halfway. I can't answer that but perhaps the Mazda engineers have been driving VWs lately; my friend's wife's Passat's clutch is the same way, you just about have to take your foot off before it grabs...

Originally posted by alarabie
I have mine since Monday and there is some vibration at idle, you notice it in the shifter, but otherwise it's pretty smooth. How's the idle speed?

I ask this because I remember the engine in the Gen II RX-7 GTU I drove for a while liked to "hunt" a bit when first started (the idle would drop down to about 700 then pop back up to 1500 or so then back to 700 then back to 1500, etc.)

On mine the idle speed looked to be around 900 or so and was holding fairly steady there. So it seems like this is normal which does seem somewhat odd since I have heard about the smoothness of the rotary.

I have had my car since Monday. There is a little stick vibration when not engaged, I keep my hand on the stick while driving, sits there just right and I don't feel any vibration while driving. My clutch engages at about the halfway point and is fully engaged with about 2 inches left. Other that the stick at idle or in neutral, I feel no vibration at all. Checked oil after first tank, its rock solid on the full line and clean.

Mine is like Clifford's, about halfway through and it engages very quickly once it starts. Very little vibration on mine, even before PDI.

Very little vibration for me other than the previously acknowledged shifter.

In terms of the clutch, in my opinion it's actually better to have it engage higher. Higher engage means you don't have to travel as far to make it work. That means less time with the engine less than fully engaged, and also means that it's less likely the RPM will fall under where you want them to be for the next gear - in fact, they might be above where you want them to be, slightly dragging the car faster rather than slower.

Originally posted by Chuck Clifford I keep my hand on the stick while driving[/B]

Don't do this! It puts pressure on the gear selector mechanism and wears it out prematurely. It's as bad as resting your foot on the clutch pedal all the time.

Originally posted by BillK
I ask this because I remember the engine in the Gen II RX-7 GTU I drove for a while liked to "hunt" a bit when first started (the idle would drop down to about 700 then pop back up to 1500 or so then back to 700 then back to 1500, etc.)

Mine does this for about 10 seconds when I first start it cold in the morning. After that, its very quiet at maybe 800 or so at idle.

-ss

Yes the Shifter vibrates at Idle; it’s to a lesser degree after you’re in 2nd. The clutch does catch on right before you let off, its a very forgiving clutch I hadn't drive a clutch in a year nor a rotary and didn't stall it once, bogged down pretty well though. You tend not to notice the shifter vibration when you’re driving too.

The idle on a fresh rotary is all over the place. This is normal. When the seals seat, you'll see a much more stable idle.

I'm not certain about this, but I think it has nothing to do with the rotary engine, but rather has to do with the linkage to the transmission. Most cars have cable linkages to the transmission, which reduces vibration but also gives a feeling that's described as "rubbery" or "vague" in magazine reviews. A benefit is that it doesn't transmit the vibration from the engine as well. A direct linkage with the transmission gives much better feel, but at the cost of vibration.

Hey, I found some links. Check these out for some reading on a related transmission:

http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=6;t=009411
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=6;t=007799
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=6;t=013981

I love the Miata forum. Every question has already been asked. :) Too bad most of them are scared of rotaries. :(

Originally posted by Lensman
Don't do this! It puts pressure on the gear selector mechanism and wears it out prematurely. It's as bad as resting your foot on the clutch pedal all the time.

Oh man, is this really true or just one of those purist beliefs? I've never heard resting your hand on the shifter is gonna wear things out. Keeping my hand there is the cool thing about driving stick. Do I really, really have to give this up to (along with compression/engine/trannie braking?)

My idle is about 1000, my clutch engages very low almost to the floor, I have to be careful when I stop and clutch, if I'm nor all the way in it grabs a little bit. I really like it like that the gear changes are really quick.

I've also heard that holding the gear stick while driving is bad for the mechanism.

I may sound totally ignorant but what is "PDI" ????

Originally posted by Maximus
I may sound totally ignorant but what is "PDI" ????
pre delivery inspection

hmm i know rest your foot on a hydraulically assisted clutch like on our big delivery truck is a BAD THING but i had not heard that it was also on a normal clutch.

Yep, resting your foot on the clutch or resting your hands on the gearshift are both bad for the mechanism - it creates slight amounts of friction that can slowly wear out the mechanisms. You may have heard of "riding the clutch", either way you're essentially doing the same thing. You're preventing the gears from being perfectly synchronized by slightly disengaging them from normal interaction. So instead of one gear being ready for its partner, there is a slight disconnect. The point when the gears retouch is where the wear happens.

FYI, older clutches used to also have the problem that you shouldn't keep the clutch fully depressed either, but newer clutches are able to completely separate the elements at this stage, eliminating the problem.

Originally posted by 8_wannabe


Oh man, is this really true or just one of those purist beliefs? I've never heard resting your hand on the shifter is gonna wear things out. Keeping my hand there is the cool thing about driving stick. Do I really, really have to give this up to (along with compression/engine/trannie braking?)

Here's (http://beetle.cabriolets.online.fr/1303/e1303c.htm) the first owner's manual I could find online with a reference to this issue. It may be a humble Beetle but the principle is the same for your RX-8!

Hehe glad to have started a side discussion :) Thanks for the answers on the vibration - makes sense with the transmission directly coupled to the engine.

Originally posted by 8_wannabe


Oh man, is this really true or just one of those purist beliefs? I've never heard resting your hand on the shifter is gonna wear things out. Keeping my hand there is the cool thing about driving stick. Do I really, really have to give this up to (along with compression/engine/trannie braking?)
Also worth pointing out that any racing school instructor will smack you on the forehead for not keeping both hands on the wheel until the shift. It is a difficult habit to break, though.

what about compression breaking?
________
Vermont Dispensaries (http://vermont.dispensaries.org/)