What's blocking me when I downshift from 6th to 4th

[Tcoat]

Originally Posted by cat94

I push straight up into neutral, then straight down letting the knob self center. I'll give it another shot on the freeway at higher rpms. And see if I still get a similar feeling

You may just not be fast enough at it.

[Ultramaroon]

Originally Posted by cat94

Just under 2k miles.



I'll stick to the simple things for now, but for an effective double clutch, do I have blip the throttle with the clutch completely released?

No, just lift a little so the pressure plate grabs. Remember, you're in neutral so the only work it's doing is pumping the fluid. Yes, there's a pump in there.

[FX86]

need more lubricant

[Ultramaroon]

Originally Posted by Tcoat

You may just not be fast enough at it.

Nope. That would be true for upshifts like the cold 1-2, but not downshifts. Unless you double clutch effectively, the synchros have to spin up the input side for a downshift.

[Ultramaroon]

Originally Posted by FX86

need more lubricant

Actually the opposite is true. The synchros will do a better job of biting through the fluid as they break in.

[Tcoat]

Originally Posted by Ultramaroon

Nope. That would be true for upshifts like the cold 1-2, but not downshifts. Unless you double clutch effectively, the synchros have to spin up the input side for a downshift.

That is what I mean. To long a delay in the rev blip of the double clutch.

[FX86]

Originally Posted by Ultramaroon

Actually the opposite is true. The synchros will do a better job of biting through the fluid as they break in.

no he needs to remove the shift boot and pour lubricant all round the shifter and gate for that slippery smooth shift feel

[Ultramaroon]

Originally Posted by Tcoat

That is what I mean. To long a delay in the rev blip of the double clutch.

Ok, yeah. Gotcha.

Originally Posted by FX86

no he needs to remove the shift boot and pour lubricant all round the shifter and gate for that slippery smooth shift feel

le

[cat94]

Originally Posted by Ultramaroon

No, just lift a little so the pressure plate grabs. Remember, you're in neutral so the only work it's doing is pumping the fluid. Yes, there's a pump in there.

I tried again 6 to 4th at ~45-50 mph but this time double clutching and blipping with the clutch completely released. Shifted very smoothly. I'll try a partial release of the clutch next time and get a feel for that.

For good measure I tried doing the 6-4th without double clutching (but with a rev match) and the blocking feeling I described was there. Definitely agree that this is a user error.

Thanks for the advice everyone!

[FX86]

Originally Posted by Tcoat

Not all gears are created equal and without looking it up I believe there is a much larger range between 6th to 4th then 5th to 3rd. I don't think I have ever run into a situation where I had to go down two gears to accelerate though. Usually one gear is plenty for any passing needs I have while street driving. What RPMs are you cruising in to need to downshift 2 gears? If you are too low to start with then I could see needing to go down two but otherwise that is pretty extreme.

hmm really? i feel that i need to downshift to 3rd from 5th just to get any serious power in order to over take someone unless i'm at highway speeds then 5th to 4th is good enough most of the time

[mazeroni]

Originally Posted by cat94

I push straight up into neutral, then straight down letting the knob self center. I'll give it another shot on the freeway at higher rpms. And see if I still get a similar feeling

Ah, freeway speeds are a bit different. The shifter is far less friendly when it's spinning that fast. While I don't think it should be so hard to get into 4th, to me, it sounds like the synchros just aren't worn in. How is the 6>5>4 downshift? I tend to go through each gear because I always think in the back of my mind that I'll do a 6>2 at 80 and blow the engine.

But as I mention, my transmission is worn in. I don't need to rev match either. Though it does help a lot.

You may need to just plan out your passes more and just go down through the gears. Meaning, go to 5th and off the clutch, then do the same down to 4th. You might get stuck in slower traffic for a while until things wear in.

[Ultramaroon]

Originally Posted by cat94

I tried again 6 to 4th at ~45-50 mph but this time double clutching and blipping with the clutch completely released. Shifted very smoothly. I'll try a partial release of the clutch next time and get a feel for that.

It's technically not a double clutch unless you engage the clutch. @Stang70Fastback brought to my attention that even with the clutch fully disengaged he (and I confirmed) that there is still enough purchase to spin up the input shaft. I don't remember if his clutch pedal is adjusted down but mine is set to what I consider minimum reasonable disengagement.

[Stang70Fastback]

I have yet to read this entire thread, but I skip gears all the time when shifting - in just about every possible combination. 2-4, 3-6, 6-4, 5-3, etc... and have never had any issues, or needed to double clutch or anything to make it happen. As long as you match the revs, you shouldn't have an issue with a properly functioning transmission. It should function just like any "normal" up/downshift.

There is nothing requiring you to go through every gear during the shifting process. Some people think shifting from 3rd to 5th is "strange" or "unusual" or "wrong," but it's no different than shifting from 3rd to 4th on a 4 speed transmission. We just happen to have more gears in between to choose from. There is no reason why you NEED to follow any specific progression. When you're riding your 18 speed bike, you don't shift through every gear to get to the one you want. You spin those levers right to the gear you want, and the chain jumps to that spot on the sprocket (probably a bad example, since the chain actually does "climb" through the gears.) Point is, you only need to use the gears you NEED to use. The rest are there just in case! You aren't required to use them all. You could use just 1st and 4th for the life of the car if you decided to.

EDIT: I was wrong, lol.

[Ultramaroon]

Skipping gates without without matching up puts a tremendous additional load on the synchros. The energy dissipated accumulates at the square of the velocity so it makes a big difference.

Spread the wealth. It's not necessary to engage the clutch in each gear, just rake through all the gates if you're not double clutching.