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Discussion Starter #1
I haven't noticed any power loss during acceleration however, after reaching 85mph it starts acting like it is running out of gas. Also when cold starting I put choke on all the way and as it warms the rpms rise on there own up to 4,000 rpms. I am at a loss please help if anyone knows anything or experienced this before? 97 carb model
 

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Discussion Starter #2
I forgot to Mention that after the bile is warmed I smell a little gas in the exhaust. Not a lot but, noticeable
 

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Discussion Starter #4
Thank you leighb for you help. I am not really experiencing rough engine. During acceleration past 85mph the motor cuts out completely as if it's running out of fuel or getting way to much fuel. I have zero control through the throttle as the bike slows. Once I get to around 40 or 50mph the bike jumpstarts and back fires then starts accelerating again.
 

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Double check your tank vent line. Make sure the end isn't crowded shut or the line isn't kinked. It should be the smaller of the 2 coming off the bottom of the tank. Also see if there is a vent hole in your filler cap. If that's plugged you'll get the same symptoms. I'd say pop the cap when it happens but then you'll have to have 2 keys. And opening the tank as speed is gonna pretty much guarentee your getting a fuel bath. Not a good idea setting on top of a hot running bike.
 

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I don't recall there being a vent hole in my fuel filler cap. If I have one exactly where is it located?
 

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Discussion Starter #7
This issue started after doing 165mph indicated on Speedo. I tried to go fast again and experienced the issue
 

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hello from belgium
im guessing but is yours a carb version?
have you had it from new?
if not do you know if the nose was removed ?
let me fill you in
i have a 97 carb version
the use cv carbs and have a tps( throttle position sensor ) on the lhs of the bank
several points
1 the cv carbs hate forced air pressure and variations in pressure
2 the tps is a potentiometer and the track can wear and give an open circuit
3 if people before have removed parts then you may be getting forced air to the carbs making the sliders jump about like mad
the result of this is like bogging or running lean
the result of the tps failure is surging which can be violent
the result of both is an over lay of both
the key bits are
1 that the tps has a constant increase in ohm reading as you turn it and no open circuit parts on the track
you can test this via a multimeter
the tps is kind of hidden by the upper frame and is not easy to remove if the screws are oem tight
careful as there is a little plastic adaptor plate that mates the shaft to the sensor and it can be very easily lost( its of course black to make it harder to find )
also guess what the parts are no longer available new from honda, but some can be found 2nd hand and checked
you may be able to " repair" yours by injecting contact cleaner into the housing ( i did this and it works almost like a new one - i have a nearly new one to compare the readings ...)
for the forced air some people in their infinite wisdom see fit to remove the air splitter and air guides lhs and rhs and also the undertray baffles ( little white bits )
this opens up the carbs to violently changing turbulent forced air flow and drives the carbs nutty
the only way to cure this is to find 2nd hand all the missing bits and install them so they full seal up
the guides act as a air constrictor and stabiliser making the carbs draw air and not ramming it in
the injector models have a map sensor that will compensate up to a degree for forced air but it still doesnt like wacky turbulence
why do i know this
because the former owners of my bike trashed the oem fairing and installed a chinky one and thought that all that " useless stuff "in the fairing was too tricky to put back in
mine will bog at about 70 mph if there is a headwind and 80 if there is a tailwind
i have found 2nd hand parts in germany and will fit them soon
then i can begin to collect speeding tickets...
 

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hello from belgium
im guessing but is yours a carb version?
have you had it from new?
if not do you know if the nose was removed ?
let me fill you in
i have a 97 carb version
the use cv carbs and have a tps( throttle position sensor ) on the lhs of the bank
several points
1 the cv carbs hate forced air pressure and variations in pressure
2 the tps is a potentiometer and the track can wear and give an open circuit
3 if people before have removed parts then you may be getting forced air to the carbs making the sliders jump about like mad
the result of this is like bogging or running lean
the result of the tps failure is surging which can be violent
the result of both is an over lay of both
the key bits are
1 that the tps has a constant increase in ohm reading as you turn it and no open circuit parts on the track
you can test this via a multimeter
the tps is kind of hidden by the upper frame and is not easy to remove if the screws are oem tight
careful as there is a little plastic adaptor plate that mates the shaft to the sensor and it can be very easily lost( its of course black to make it harder to find )
also guess what the parts are no longer available new from honda, but some can be found 2nd hand and checked
you may be able to " repair" yours by injecting contact cleaner into the housing ( i did this and it works almost like a new one - i have a nearly new one to compare the readings ...)
for the forced air some people in their infinite wisdom see fit to remove the air splitter and air guides lhs and rhs and also the undertray baffles ( little white bits )
this opens up the carbs to violently changing turbulent forced air flow and drives the carbs nutty
the only way to cure this is to find 2nd hand all the missing bits and install them so they full seal up
the guides act as a air constrictor and stabiliser making the carbs draw air and not ramming it in
the injector models have a map sensor that will compensate up to a degree for forced air but it still doesnt like wacky turbulence
why do i know this
because the former owners of my bike trashed the oem fairing and installed a chinky one and thought that all that " useless stuff "in the fairing was too tricky to put back in
mine will bog at about 70 mph if there is a headwind and 80 if there is a tailwind
i have found 2nd hand parts in germany and will fit them soon
then i can begin to collect speeding tickets...
LOL how true it is, good luck and enjoy the g force.

STex
 

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I don't recall there being a vent hole in my fuel filler cap. If I have one exactly where is it located?
There is a vent ring that is hidden inside the tank under the filler neck. A tube runs from it to the bottom if your tank. If you prop up the tank you should see 2 lines coming down the clutch handle side of the bike. One is large about 3/8 diameter the second is smaller that is the tank vent line. Make sure it's not kinked or clogged.
 
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