I contacted Spec and this is their response:

You've been misinformed...gear noise from the single mass flywheel occurs also under load, especially at lower rpms and lugging.

Regards,

SPECTech

So I guess it is normal. I wonder why it is tho?

 

That sounds crazy that it's clattering even when loaded in gear. From the manuals I had, I only experienced like you stated during neutral coasting, not while in gear.

 

Slightly off topic here. UltimaX99, did you install the flywheel and clutch by yourself? If you had a shop installed them for you, how much did they charge you? Was it Lexus dealer?

What is the benefit of having 2nd stage clutch? I'm pretty happy with my stock clutch as of now. Why didn't you use F-Sport clutch?

 

I did not install the clutch and flywheel myself. I went to an independent mechanic. The Lexus dealer won't install aftermarket parts on your car unless they sold it to you. The shop charged me $400 for the installation.

The reason why I changed the clutch was because I figured since I'm going to change the flywheel, I might as well change the clutch too since I'll have the transmission apart. The stage 2 clutch provides more "bite." Looking back at it now, I probably could have gone with the stage 1 clutch over the stage 2 clutch. I probably wouldn't be able to tell the difference in feel and would've saved me a few bucks. I didn't go with the f-sport clutch because at the time, I was planning on getting stage 2 clutch. If I had to do it all over again, I probably would have considered the F-sport clutch.

 

 

Hmmm... I missed out on a lot in the past few months! I'd be interested in the Fidanza flywheel and Spec clutch when mine feels like it's worn out. But this problem concerns me. Will it be addressed by either Spec or Fidanza?

 

Bump.. anyone have any more info on this combo? Tests? Thoughts?

 

This thread got moved to performance, but no one's responding to my inquiries!

https://www.clublexus.com/forums/per...ec-clutch.html

There were at least 13 people part of the Fidanza flywheel group buy; does anyone else have anything to add about their experience with the new flywheel and perhaps a new clutch? Noticeable difference?

Thanks in advance!

 

+1 for long(er) term updates.

 

pepos posted some good results here:
https://www.clublexus.com/forums/per...stage-2-a.html

Hoping for some more feedback!

 

well to my experience
i have a 2005 subaru liberty gt (legacy gt in the US)
it comes with a dual mass flywheel
iv had a manual is250 and yes i know how **** the tranny is
my liberty felt the same silky smooth but when you start giving it abit you always crunch gears or over rev.
after i installed a singlemass flywheel (ligher than OEM)
the driving has immensly improved.
though the downside is
you get alot of vibrations when the car is under load and on idle at the lights you can hear increased noises. (under load as in 5-6th gear at 60km/h fully pressed pedal)
its not enough to get you worried but enough for you the hear.

 

FWIW, the chatter is often the synchros vibrating. My Supra's Getrag will not chatter if I put pressure on the 1st gear synchro but not enough to actually slide it into gear. More often than not, you're hearing transmission internals rattling because they're getting vibration normally dampened out by the "dual-mass" flywheel. Keep in mind, the gearbox engineers made those synchros smaller and lighter than they normally would because the friction disc is considerably lighter when it doesn't have any driveline damping in it. Take the damping away, and you'll suffer (so will your synchros over time, AMHIK). I think the pic below says it all...



As crappy as the RA-62 design is, I'm not at all surprised it makes noises at more than just idle. When my Supra had a light flywheel, I just called it the cost of better performance. When I put in the HKS triple - well, let's just say a coffee can half full of ball bearings on a paint mixer is definitely quieter - I decided racing parts are just not suitable for street duty and went back to the quiet boat anchor dual mass LuK flywheel.

 

Mine is still not making any noises at all and i have done 9000 miles up to now.
I'm very happy with this mod and i beleive that if someone experiences any noises or vibration it's because of a crapy install or suffered RA62.
I always use MOTUL 75-90 as gear oil

 

I started getting clutch chatter tonight. I was driving with a full car of people Starting out in first gear is when i would get the clutch chatter. Also when i was going up hill and starting back out in first i was getting almost a screeching noise coming from the transmission. Would that be something that's caused from the same problem that causes the clutch chatter?

My car is a 08 IS250 FWIW

 

That sounds a lot like what I've been getting. It sounds really bad. Mine goes away or doesn't make as much noise after driving for a while, but comes back the next day or after the engine has cooled down. How long did you start hearing the clutch chatter after you got it installed?