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I kick up to the last gear and can't get up to more than about 61mph. Suggestions?
 

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Need more info. Bike mileage, riding conditions, etc. If you're going up a hill, into the wind, and it's cold out, it's not going to want to go too fast.

Quick check is to make sure your air box is clean and free of restrictions. Papers get sucked in there a lot.
 

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any sprocket mods ??? over geared ???

fuel quality ??
tyre condition ??
 

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I kick up to the last gear and can't get up to more than about 61mph. Suggestions?
You need to go closer to the redline in 5th gear. Traditionally, Honda's 6th gear on small engined bikes (all that I can discuss from experience) are set so that you can just achieve the redline going downhill with a modest tail wind in 6th gear.

This is a small engined bike. You have to rev it, not lug it.
 

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6th gear ratio is 'overdrive' ratio, less than 1:1
thus as jsonder observes, not designed for
continuing acceleration, rather more like
getting her up to speed then dropping
into a lower rev/more fuel efficient
overdrive gear ratio..

just as first at around 3.3:1 is designed for
overcoming gravity, uphill, loading, wind etc
top at around 0.96:1 would benefit from
negative gravity or downhill, lower loading
or a tailwind.. or starting out from high revs
[all else being equal] so as to be able to
start in top from higher revs before
inevitably evening out/dropping revs..

if you swap to a 13 tooth countershaft sprocket
she will have somewhat better ability to sustain
revs thus speed, or a 15 tooth cs for even better
economy by sustaining speed at lower revs..

theres only a certain potential for power to weight
which in a 250 single designed to include economy
isnt going to have the luxury of powering thru
air resistance at higher speeds..

higher tyre pressure is an eg of little things
that can contribute to lower rolling resistance
etc, for better cruising speed with economy..

check threads her for members expert in
this use of their motorcycles for high mpg etc
such as sendler and co..
 

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I kick up to the last gear and can't get up to more than about 61mph. Suggestions?

in case, you are still on a 14 sproket and/or not a 150kg person or driving uphill, against strong headwinds and the rpm is around [email protected] 61mls

check compression

if rpm is much higher, check clutch

out of own experience, I cant really follow the '6. is not for accelerating', ect., thing
in special not @about 100km/h, 6000 rpm.

my bike, if opening the throttle in 6. and at about (shown on display) 100 km/h / 6000rpm, is going to 7000, 8000, ..... rpms.
and the speedo is showing the change from 100 via 120, 130, 140,...
I expect all of our bikes are be able to do so.
of course, it would accelerate , is accelerating quicker, if using the lower gears closer to redline.
But in case your bike is in normal conditions, not rev/speed limited and the load / wind is not to heavy, there must be a engine problem / limitation.
 

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You need to go closer to the redline in 5th gear. Traditionally, Honda's 6th gear on small engined bikes (all that I can discuss from experience) are set so that you can just achieve the redline going downhill with a modest tail wind in 6th gear.

This is a small engined bike. You have to rev it, not lug it.
At 61 mph he should be at roughly 6.000rpm were the engine starts to get it's torque so there is no way this is a lugging issue. I usually shift to 6th at ~45 - 55 mph and can accelerate just fine.
 

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I kick up to the last gear and can't get up to more than about 61mph. Suggestions?
At what speed is the O.P. shifting into 6th gear?

I ran my old 250 in the 50%-75% of redline (mostly 50-60%) for normal riding to avoid being too far down the torque curve.

Otherwise, it could well be a clutch starting to fail.
 

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I don't think it matters. If he can reach 61mph he should have the revs to accelerate all the way up to 80+ mph in 6th gear.
Exactly!

Main question:
R0gue4 is not posting much.
But has he had ever other results in 6.
If yes, what did (he) change
If not, is it a sec. hd. bike, electronically limited?
Can he go quicker in 4. or 5.?
 

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I don't think it matters. If he can reach 61mph he should have the revs to accelerate all the way up to 80+ mph in 6th gear.
The patience of the O.P. is unknown, so while I agree with your assessment (which does suggest that the clutch is going out), I'd like to be sure that it isn't newbie misconceptions before suggesting new clutch plates.

And if it is the clutch, he should hear the engine winding up and be able to see that with the tach. None of that was included in the description.

It could be something as simple as rodent debris in the airbox, or an oiled up air filter.

Back to basics, air, fuel, and spark. ;-)
 

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I agree with John, given the lack of information in the opening post, one could speculate and play the guessing game until the cows come home... without some specific details from R0gue4, I wouldn't waste time on this thread.
 

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Discussion Starter #14
Bike's a 2011. Purchased used in 2013. Took about a year working my way up to venturing onto the interstate. Reaching 70mph and above in last gear wasn't an issue then. Now I kick up to last gear and can max out the throttle with no jump from the rpm needle and i can't get above about 61mph.
 

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...
Took about a year working my way up to venturing onto the interstate.
....
You sure, a motorcycle is a good choice? For you? 0:)

But:
Get the compression checked.
How is the mileage?
I understand your last post, that you are not be able to get quicker in 5. gear.
Is that right?

I think, you need to see a repair center.
Or you trolling. (No offense ;-)
 

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Few cbr250r in Malaysia are reported the same symptom before piston seized. If it accompanied by rough engine sound, perhaps almost confirm the crank shaft bearing problem.Hope this might help.
 
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