I think part of the reason is debris and part of it is fluid breakdown. A lot of things will affect the fluids viscosity over time, like mechanical shear and heat. Synthetic fluids are more resistant to thinning affects of shear and heat and give better filming characteristics.

 

Happen to me few times, and I noticed this happens due the revs falls too low during the shift.


When I shift at low speeds I found that it won't grind if I press the clutch a tad earlier than depressing the accel. You will have like a little engine rev build up (1k or so) during that put third and release.
Had no grinding doing that way.

My tranny is up to date with fluid change. Yours might need fresh one.

 

Thanks everyone !

I am going to a friend's place tomorrow where I can jack up the car and will change the transmission and differential fluid.

I was debating if to also replace the brake and clutch fluid at his place but my nearby dealer does both for $80 so I might just let them do it. Besides that I did not find the ATE blue brake fluid today (only found some Prestone DOT 3 synthetic brake fluid) and Honda recommends you use their fluid otherwise you degrade the performance, blah, blah, blah(maybe just marketing ?).

Will let you know the results.

Besides that I am so fascinated about this car. I am not that much into cars and so but this one is like when you get a new girlfriend and you keep thinking of her when you are away from her ;-) ... I'm sure you know the feeling.

I don't know what but there is something magical about this car ...

Sorry ... got carried away ;-) ...

 

notchy 2nd-3rd gear is pretty common. I have a fully rebuilt trans and new clutch and still experience notchy 2-3 gears even using Amsoil MTL!

 

fluid breaks down and affects various properties. tranny fluid better look brand spanking new every time you drain it or else you have problems.. aka there shouldn't be enough particles of anything in there to affect performance.

 

Is this a design flaw of the S2000 gearbox then ?

I read that year 2000 and 2001 S2000s have the 1st to 2nd gear grind issue. Mine is a 2002 and I didn't see that issue.

Do the models of all the years have the 2nd-3rd notchiness issue ?

I didn't have the chance of changing the fluids yet (it was raining down here in the weekend).

 

Its a COMMON issue, so no it does not happen for all s2k's from that year.

 

OK, I replaced the transmission fluid and the shifting is somewhat better. I still get some notchiness from 2nd to 3rd and now there is a bit of that from 1st to 2nd.

I replaced the diff fluid last night too even though this should not affect shifting.

I also tried to gravity bleed the clutch but I managed to run dry the master cylinder so I might have some air into the system now :-( ...

What happened is that I opened the bleeder too much and the fluid was flowing out pretty quickly. I was watching air bubbles come out and while doing that the master cylinder ran dry.

I guess I should have opened the bleeder only 1/4 turn or so as specified in the DYI thread. I have a feeling that some of the air went in and I was seeing lots of bubbles (before the master cylinder ran out of fluid) because I opened the bleeder too much. Am I on the right track here ?

If there was indeed air in my clutch system that should also improve shifting.

Will try to fix that in the next few days. Do you guys know if I can get the air out just by gravity bleeding ?

 

I've read you can redo the gravity bleed until you see no bubbles. Its better to spend some extra $ on fluid vs spending $$$ on parts.

 

Thanks blah !

I am thinking of just reusing the new fluid and bleed the clutch until I see no bubbles. Is there a very good reason of not doing this (reusing the new fluid) ?

I know that the break fluid id hydrophilic but I just opened the bottles yesterday.