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in the manual it says recommended downshift speed:
6 to 5 - 28 mph
5 to 4 - 22 mph
4 to 3 - 16 mph

say im going 40 mph and I need to slow down. Does that mean I should be using my brakes until I reach 28 mph then downshift ( clutch in, roll off throttle, downshift) with no blipping necessary? or is this the recommended speed to engine breaking??
 

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Those speeds seem really low, but since I currently don't have a CBR250, I can't say.

In my opinion if you are doing 28 mph in 6th gear, even though you are coasting, you have no power if you need to accelerate or react to anything. I prefer to downshift at higher speeds, maybe not quit engine braking but at a speed that allows me to accelerate and be in the correct gear at the moment so the bike responds.
 

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IMO, those mph numbers in the O/M are ridiculously low. For example, yesterday I was at 65mph in 6th gear when I began going up a moderate grade. When the speed and rpm dropped to about 60, I grabbed 5th, bringing up the rpm's as I released the clutch lever to match rpm to road speed. It was a seamless shift to maintain road speed and rpm up the hill. For me, it's a very "seat of the pants" feel for the given situation when a downshift is required. The goal is to match rpm and road speed for a given situation, be it acceleration, deceleration, or maintaining steady speed, and using the gearbox to do that. But again, I think those numbers in the O/M are so low, that you would find yourself lugging the engine, which is not a good thing. With the exception of the 1 to 2 up shift, the rest of the up shift points given in the O/M are very low as well, and would have you lugging the motor and accelerating like a turtle. Don't be the turtle...
 

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in the manual it says recommended downshift speed:
6 to 5 - 28 mph
5 to 4 - 22 mph
4 to 3 - 16 mph

say im going 40 mph and I need to slow down. Does that mean I should be using my brakes until I reach 28 mph then downshift ( clutch in, roll off throttle, downshift) with no blipping necessary? or is this the recommended speed to engine breaking??
6th to 5th should occur @ 45ish. If you are in 6th at 28mph, something is not right. Don't you feel it lugging?? I am in 2nd going to 3rd @ 16 or if I am cruising at that speed, I may just stay in 2nd.
 

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6th to 5th should occur @ 45ish. If you are in 6th at 28mph, something is not right. Don't you feel it lugging?? I am in 2nd going to 3rd @ 16 or if I am cruising at that speed, I may just stay in 2nd.


yeah thats way too low, 6th gear is lugging around 35-40mpg for me

i'll be in 4th around then

might add that i can get in 3rd and give no gas at all and the bike will roll around at 16mph without stalling (clutch fully engaged)
 

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yeah thats way too low, 6th gear is lugging around 35-40mpg for me

i'll be in 4th around then

might add that i can get in 3rd and give no gas at all and the bike will roll around at 16mph without stalling (clutch fully engaged)
35-40mpg?

Better get a tune-up. ;)
 

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This bike wont pull below 100 kph 60mph too well in 6th (6000rpm), so I'm not too sure where these figures come from.

It does 78kph /48 mph in 2nd.
 

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I think it means dont go below idle in gear.

The Aussie manual says- 'Ride it like ya stole it'
 

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I know doesn't sound right but I'm trying to figure out why the manual says so? maybe it has to do with breaking in the new engine? I don't know.
No. There is no manual to "breaking in an engine".

I agree with Aufitt. Just ride it!
 

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No. There is no manual to "breaking in an engine".

I agree with Aufitt. Just ride it!
Probably what Aufitt was saying about going below idle. If some interweb savvy person checks gearing commander I think you'll find those speeds listed in his manual are right near where the injector goes back on idle sequence.
 

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This is not all that different than my current KLX250s. They are not talking about accelerating which would be lugging the engine. If you are slowing and the clutch is engaged and engine braking these should not bring the RPM lower than idle. My guess is that it will lead to smooth down shift.

Sure you can downshift at higher speed but it will require more rolling on the throttle to be smooth.
 

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I would figure 7-10 mph per gear. :)

I agree. Drive it like you stole it. I was redlining mine and drag racing it, popping wheelies to get the best launch against my brother's 1400cc cruiser the day I took it off the lot.

Don't worry, you're not going to hurt it. If you're that worried, buy the extend 4+ year warranty. :)


Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

What's The Best Way To Break-In A New Engine ??
The Short Answer: Run it Hard !

Why ??
Nowadays, the piston ring seal is really what the break in process is all about. Contrary to popular belief, piston rings don't seal the combustion pressure by spring tension. Ring tension is necessary only to "scrape" the oil to prevent it from entering the combustion chamber.

If you think about it, the ring exerts maybe 5-10 lbs of spring tension against the cylinder wall ...
How can such a small amount of spring tension seal against thousands of
PSI (Pounds Per Square Inch) of combustion pressure ??
Of course it can't.

How Do Rings Seal Against Tremendous Combustion Pressure ??

From the actual gas pressure itself !! It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall. The problem is that new rings are far from perfect and they must be worn in quite a bit in order to completely seal all the way around the bore. If the gas pressure is strong enough during the engine's first miles of operation (open that throttle !!!), then the entire ring will wear into
the cylinder surface, to seal the combustion pressure as well as possible.


The Problem With "Easy Break In" ...
The honed crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear. The rings quickly wear down the "peaks" of this roughness, regardless of how hard the engine is run.

There's a very small window of opportunity to get the rings to seal really well ... the first 20 miles !!

If the rings aren't forced against the walls soon enough, they'll use up the roughness before they fully seat. Once that happens there is no solution but to re hone the cylinders, install new rings and start over again.

Fortunately, most new sportbike owners can't resist the urge to "open it up" once or twice,
which is why more engines don't have this problem !!

An additional factor that you may not have realized, is that the person at the dealership who set up your bike probably blasted your brand new bike pretty hard on the "test run". So, without realizing it, that adrenaline crazed set - up mechanic actually did you a huge favor !!
 
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