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Discussion Starter #1 (Edited)
Greetings Forum Members,

I have to get this odd/perplexing concern off my chest.

By way of brief background, I've ridden H-D M/Cs for the past twelve years, exclusively...

I generally blip the throttle and down shift prior to entering a fast curve, and/or blip the throttle when decelerating and simultaneously down shifting while coming to an abrupt stop, i.e., traffic light. I grew up racing cars and you always blipped the throttle/gas pedal when downshifting to match revs...

I've noticed that when preparing for downshifts on my '12 RT, the bike stalls/coughs (I can tell it upsets the bike) when I engage the clutch and then blip the throttle prior to downshifting. Do any of you experience this as well?

I never had any issues w/any of the several H-D M/Cs I've owned. Now that I think about it, I never had a problem with the many Japanese bikes I owned back in the day either... :confused: :mad:

Tks/Cheers,

B
 

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I like blipping... never a problem for me nor my engine...

Also try learning the habit of pre-loading the shifter for both Down shifts and Up shifts... just lightly press/lift the lever with your toe a little before pulling the clutch... shifts like buttah....
 

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Discussion Starter #3
^^^ Tks for the feedback hopz. I'll give your tip a test this weekend. I'll make sure the dealer has a looksie on this issue when I take the bike in for it's first service.

This bike really does grow on ya. What charm. Absolutley love it!

Tks/Cheers,

B
 

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Benito - The coughing and stalling that you mention is in my opinion a problem that needs to be corrected. The dealer ought to be able to diagnose and fix it.
 

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Throttle "blipping" is used to effect clutch-less down shift. If you apply downward pressure on the gear selector and "blip" the throttle, it will change gear smoothly without the use of the clutch. In a similar fashion, applying upward pressure on the selector and momentarily backing off the throttle will result in a smooth up-shift. This makes for faster shifting and prevents compression lock-up that can occur when the clutch is released too abruptly under hard deceleration (into a tight corner for example). It also assists in smoother transition and control when approaching corners.

This is a feature of any sequential transmission. If you try doing this in higher gears to start off with, you will find it surprisingly easy and smooth. As you get used to it, you can do it in lower and lower gears.

I commute in city traffic every day and strip all the gear off and use my RT for track days and rarely use the clutch unless I am stopping. Depending on speed, it is useful to just touch the clutch when changing back to 2nd or 1st (on the track, I might do this when changing back to first - once again, depends on speed and conditions).

Once you get used to doing this, you will find it natural and quick.

... and just in case you were wondering, no, this does not stress components or cause accelerated wear or breakage.
 

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I totally agree with 6north. I rode and raced off road for many years and only used the clutch to start off or some slippage when doing some type of steep climbs. On the RT, I find that using a slight clutch between 1st and 2nd makes for an easier up shift in urban situations, but with proper shift lever loading and throttle movement on or off, all other gear changes are quick and smooth. All we are really trying to do is get to 6th and enjoy the smooth highway speed ride, right? tomp dd50
 

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dirtdreamer50 said:
I totally agree with 6north. I rode and raced off road for many years and only used the clutch to start off or some slippage when doing some type of steep climbs. On the RT, I find that using a slight clutch between 1st and 2nd makes for an easier up shift in urban situations, but with proper shift lever loading and throttle movement on or off, all other gear changes are quick and smooth. All we are really trying to do is get to 6th and enjoy the smooth highway speed ride, right? tomp dd50
Except when you are on a track or twisty road stalking "sports" bikes when you get into 3rd and 4th gear corners - a little rear brake helps it tip in quicker and the rock solid front end will help you see off most contenders - only exception to this is if you come across a good rider on a GS with decent tyres - very hard to stay with them. After you have done all that, you pop it into 6th and enjoy a leisurely cruise home.
 

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Discussion Starter #8
All,

In reference to my initial thread, I saw that a Forum Member from the Land Down Under, posted on another thread that you are not supposed to shut down/power off abruptly on an RT, b/4 or in a corner due to the longitudinal crankshaft...

Can someone enlighten me on longitudinal crankshaft? How does this effect the handling of the RT?

Could the issue that I've experienced on my initial thread be what I'm experiencing when the bike gets goofy when I blip the throttle while downshifting and making a turn???

Tks/B
 

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I stopped blipping years ago because of the shaft drive. With the chain and belt driven bikes I have owned it worked ok. With the BMW, I stay on the gas and shift or break only enough to keep the rear drive shaft loaded, power through the corner then shift again(clutch optional)... Stop Blipping ;)
 

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Benito said:
All,

In reference to my initial thread, I saw that a Forum Member from the Land Down Under, posted on another thread that you are not supposed to shut down/power off abruptly on an RT, b/4 or in a corner due to the longitudinal crankshaft...

Can someone enlighten me on longitudinal crankshaft? How does this effect the handling of the RT?

Could the issue that I've experienced on my initial thread be what I'm experiencing when the bike gets goofy when I blip the throttle while downshifting and making a turn???

Tks/B
The crankshaft runs front to back rather than side to side most bikes. There is some gyroscopic effect associated with any rotating machinery, however, it is more easily felt on the RT because of the orientation of the crankshaft which can make the bike rock to one side when you accelerate (you can feel it when the bike is stationary and you rev it up - the bike wants to tilt to the right). The same occurs on in-line engines, however, because the crankshaft is across the bike, the tendency is to want to tip the bike forward or backward. Because of the wheelbase etc, this is not detectable.

In theory therefore, revving the engine during cornering could effect the lean angle, however, compared to other cornering forces, I do not think that the gyroscopic effect from the engine is significant - for example the force from the rotation of the wheels is much greater.

In general, backing off in a corner should be avoided on any bike as it will cause the bike to dip into the corner. Neutral throttle, or slight throttle on at the kissing point in the corner then ease power on as the bike stands up. decelerating and down-shifting should all be complete before you start to tip into the corner. Some rear brake, or even front brake part way through the corner can assist with stability, however, this should only be light. You need to practice this on a track or isolated road where you know the corners very well and can compare the feeling with and without the trailing brake. I certainly notice a difference on the RT when applying some rear brake in tighter corners - but timing an pressure are everything, so would not suggest you go out and start doing this without some practice first.

my $0.02.
 

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Sixty6north said:
only exception to this is if you come across a good rider on a GS with decent tyres - very hard to stay with them. After you have done all that, you pop it into 6th and enjoy a leisurely cruise home.
True!
And I have rode with a few.
Usually 10+ years my elder! :bowdown:
 

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A much better term than "blipping" is rpm matching.

It's not just for downshifting, either. For example, I need to do it those times I attempt a 6-7 shift on my 6-speed bike.

It's really not just give it a "blip" and hope it works--rather it really is a process of getting the engine to the *correct* speed before clutch engagement. Close is better than idle, but exact is better yet. You don't have to let go of the throttle before engaging clutch.

I don't ride chain drive bikes, but there sure is zero problem doing it successfully on shaft drive BMWs and I'd recommend it for sure.

It's maybe a little bit more complicated on fuel-injected bikes than on carburetored Airheads, as the former can shut off all fuel flow during the process while the latter don't. The abrupt fuel cutoff is the real problem, NOT longitudinal crankshaft. That is, anything not smooth can cause problems, handling included.

RPM matching should be performed 100% of the time on anything with a manual transmission.

Today's supersophisticated super cars as in Mercedes AMG with auto transmission have computer systems to match rpms prior to downshift, which can be done manually or left to automation. Listen to a Formula One engine, too--it's rpm matching on downshifts.
 
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