how to shift from 4th gear to 3nd gear? - Page 3 - BMW S1000RR Forums: BMW Sportbike Forum
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post #21 of 37 (permalink) Old 11-07-2012, 03:21 PM
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Originally Posted by Serious View Post
You're right nothing can be learned from the best motorcyle racers in the world. I should just listen to the guy on the internet.
Not everything can/should be applied to street riding from the race track

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post #22 of 37 (permalink) Old 11-07-2012, 03:37 PM
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I'm not making anyone listen to me, you're free to make your own decision. I will however offer my experience and knowledge of engines and transmissions top help them make an educated decision. Just because someone does something a certain way doesn't make it right or wrong.

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post #23 of 37 (permalink) Old 11-07-2012, 05:13 PM
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Originally Posted by russianvr4 View Post
can you please explain how exactly is it hard on the dogs?
Because you're slamming the gear dogs into their slots under pressure.

Upshifting, everything is working in your favor as the rev drop you get as you roll off the throttle is exactly what you need to get a nice rev match in the next higher gear so the dogs can engage without pressure and with matched speed. This is the principle that allows BMW to offer shift assist that is intended for upshifting only. When downshifting, rolling off the throttle to relieve pressure is working completely counter to the rev increase you need to match road speed and engine speed in the lower gear so generally you're forcing the bike into the lower gear with the dogs either under pressure, rev-mismatched, or both.

Some think that they have the timing down to back out of the throttle, then rev the throttle just right so that they "catch" the intermediate period when the bike is between gears and they can get enough rev increase for the lower gears. They're deluding themselves. Transmission teardowns of those doing routine clutchless downshifting invariably shows excessive wear on the shift dogs. And as I said before, transmissions are ridiculously tough so it will seem to be peachy for a thousand or three miles until the bike suddenly starts jumping out of gear and you're looking at a $5K repair bill.

To the OP, you can be conservative, take better care of your bike, follow BMW's recommendation and work on your rev-matched downshifting using the clutch as BMW (and all bike mfgs) recommend. Or take the advise of a vocal minority on the internet. Your choice.

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post #24 of 37 (permalink) Old 11-07-2012, 05:25 PM
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i've been riding clutchless for at least 20k miles with ZERO negative effects, my trans does not pop out of gear, shifts up and down perfectly and smoothly, and neutral is easy to find.

i'll post up some more technical stuff when i get home.

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post #25 of 37 (permalink) Old 11-07-2012, 06:51 PM
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Originally Posted by QuikSanD View Post
It's implied
I had to re-read the thread cause I couldn't stop laughing! Interested for russians later posts on this. I've been doing this for a little while (2.5k miles) and haven't seen or felt anything off as well


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post #26 of 37 (permalink) Old 11-07-2012, 07:05 PM
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Originally Posted by russianvr4 View Post
i've been riding clutchless for at least 20k miles with ZERO negative effects, my trans does not pop out of gear, shifts up and down perfectly and smoothly, and neutral is easy to find.

i'll post up some more technical stuff when i get home.
Just because something hasn't failed yet doesn't mean you aren't abusing or putting excessive loads on components. That is how fatigue failures occur.

Have you actually torn down a gearbox to examine the shift forks & dogs after 5000+ clutchless downshifts? Or are your assumptions based the fact that nothing bad has happened yet?

Its like saying "Leaving your house unlocked is completely safe because for the last two years the lock on my front door was broken and nothing was ever stolen..."

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Originally Posted by Kacolorado View Post
I had to re-read the thread cause I couldn't stop laughing! Interested for russians later posts on this. I've been doing this for a little while (2.5k miles) and haven't seen or felt anything off as well


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Do about 10000 more shifts like that then tear your gearbox down. See how it looks then.
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post #27 of 37 (permalink) Old 11-07-2012, 07:25 PM
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Not trying to spit in anyone's soup here, there are arguments for both, and remember, not talking about track riding. You could be right and I have screwed myself for future repair, but you have to argue with more than "trust me." To be fair Russian is doing the same with his argument, so I'm not being bias.

Every thread I've read on this subject fails to produce hard facts (haven't gone out of my way to search either) I would like to see pictures or historical data so if I am doing something wrong, I can immediately remediate and warn others with facts. Again, just trying to get some knowledge, not argue lol.


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post #28 of 37 (permalink) Old 11-07-2012, 07:49 PM
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http://youtu.be/b9ExUQYu0-k

Hopefully that linked worked. Literally googled "clutchless downshifting motorcycle" and the first thing that popped up was a video of a s1k from CSS, coincidence!? Lol


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post #29 of 37 (permalink) Old 11-07-2012, 07:55 PM
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Originally Posted by Serious View Post
Just because something hasn't failed yet doesn't mean you aren't abusing or putting excessive loads on components. That is how fatigue failures occur.

Have you actually torn down a gearbox to examine the shift forks & dogs after 5000+ clutchless downshifts? Or are your assumptions based the fact that nothing bad has happened yet?

Its like saying "Leaving your house unlocked is completely safe because for the last two years the lock on my front door was broken and nothing was ever stolen..."



Do about 10000 more shifts like that then tear your gearbox down. See how it looks then.
actually i have, and it looks spectacular!

here's the deal. when you use a clutch, it disengages the input shaft from engine speed and its spinning freely, you then mash the gear shifter down not knowing wether the input shaft is spinning the same speed as the counter shaft. when you rev match, you ensure both shafts are spinning at the correct/same speed and the dogbones engage smoothly without any unnecessary wear.

when i do it, i barely have to use any pressure on the shift lever, maybe 10lbs worth if that, once i blip the throttle to get the rpms up, as soon as the shafts are spinning same speed the shifter slides into the next gear by itself practically. if you cant understand this, study up on how manual transmissions work, logic and physics dont lie, if you cant see it, well i cant really help you short of teaching you how transmissions work.

like i said, im not trying to shove anything down anyone's throat or make anyone do as i say. simply trying to shed some light on how/why things work the way they do. if you dont agree, thats perfectly fine, we can go our separate ways. no need to get hostile about it.

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post #30 of 37 (permalink) Old 11-07-2012, 09:20 PM
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Seriously people, its "heel & toe" not 'heal & toe'
And 'breaks' are spelled "brakes".

If you can't spell you'll never get the hang of clutch-less anything... seriously joking
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