Has anyone experienced gear grind AFTER deleting CDV?

I am trying to go through the process of elimination to see if we can narrow the cause down as much as possible. So far, model year doesn't seem to matter as the 2018 guys are also having grinds. I know there aren't very many members who had their cdv deleted, but is there anyone who are experiencing grinds with removed cdv? if noone is experiencing grinds with cdv deleted, maybe this is the root of the cause? Is there also anyone whose grinds have gone away as a result of removing the cdv?

You need a new transmission not a CDV delete. You remove that thing yourself you WILL void warranty .

If the transmission is damaged it would need to be rebuilt/replaced.

I don't see how Honda would know that the CDV has been removed if they do a warranty repair on the transmission. The technician is not going to open the slave cylinder to check if the CDV is still inside.

CDV delete is always good, even when you don't have the grind issue. The delay is so annoying....

I will say this, after removing it in my 8th gen si, I haven't had a single instance of a gear crunch. That car was so random on the grinding that it had to be it.

I would occasionally get a mild grind more of a crunch feel as if the clutch wasn’t quite disengaged. Mostly when I would shift relatively fast at low-medium rpms, particularly 1-2. I thought I was crazy. I’ve been driving manual cars for the last 15years, never had that issue. Then I started reading about the CDV and it started to make sense. I just deleted mine, changed trans fluid with amsoil, put in an SS clutch line. Shifts are much smother, clutch feel/engagement is very nice and predictable. I won’t go so far as to say it’s a whole different gear box because of it but it is noticeably improved and no grids.

I was skeptical of the CDV delete, but I will say that it was worth doing. I haven’t had a grind since the CDV removal and the car is much more drivable. The transmission is still pretty “notchy” IMHO.

It’s puzzling why Honda didn’t spend more time on this valve design, especially for the Type R. Removal seems to be the next best option.

jsyar said:

I was skeptical of the CDV delete, but I will say that it was worth doing. I haven’t had a grind since the CDV removal and the car is much more drivable. The transmission is still pretty “notchy” IMHO.

It’s puzzling why Honda didn’t spend more time on this valve design, especially for the Type R. Removal seems to be the next best option.

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Yeah, I was very on the fence with so many mixed opinions and the potential increased wear on the drivetrain. Mine is my daily and while I love driving it hard, I typically drive spirited yet conservative. Not mashing through gears at redline often, so I decided to take it out. I was able to remove it without doing any damage to the valve and figured I would try it out and if I didn't like it, reassemble. Wasn't a very hard process. Long story short, I'm leaving mine out, I like how it feels. Plus, planning to Ktune it in the near future to eliminate rev hang, which a transmission tech on here, and others, has stated is the key to reducing the additional stress. Because rev hang keeps the engine speed form dropping making rev matching more difficulty and more likely to cause extra stress if shifting too soon.

CTR1633FK2 said:

CDV delete is always good, even when you don't have the grind issue. The delay is so annoying....

Click to expand...

What's CDV?

Following

Yes, still grinding after CDV delete, albeit less frequently than before. Grinding occurs between 1->2, 3->2 and 5->4. Only thing left to try is mod the master cylinder (delete the damper).

MutatedMango said:

What's CDV?

Click to expand...

https://www.civicx.com/threads/ctr-clutch-delay-valve-removal.22065/

Update: I don't want to jinx it as I need to evaluate over a longer mileage, but it seems I may have gotten rid of grinding.

I adjusted the MASTER CYLINDER per this video*:



and it has made ALL SHIFTS much smoother. Seems like the CMC has a damper that makes clutch disengagement very inconsistent which leads to random grinding. Extending the push rod a little bit seems to allow the clutch to disengage fully every time. I also came across a solution to weld the damper holes in the CMC (removing the damper), but according to the guy in the video, merely adjusting the stock CMC is enough.

* - on the FK8 CTR (at least the Euro version) there is a stopping bolt instead of the sensor that gets adjusted in the same way.

I will report back in a while.

I just did this adjustment i driven alot of hondas and i always felt the clutch was slightly off on this car it feel too low the engagement.
So i adjusted as per the video above and i have to say every gear shift is smooth no more notchy feel.
2nd gear is seamless now and 5th
Only downside the clutch petal is slightly higher

Since we dont have a sensor like that we have a bolt as a stopper i left between 3 to 4 threads exposed

Removed the CDV valve this wkend. The initial testing was very promising. I like the way the clutch pedal felt and where it grabbed. I drove it today at a stop turned right, gunned it and shifted and I heard a grind. I'll have to watch the video above and see if that helps with the grinding. That seems to be when I experienced the grinding the most if I'm at a stop, gun it while turning then shift.