i have an annoying problem that i hope someone has the answer to.
after hard braking for a corner, when i get back on the throttle my vtr hesitates as if it is starved of fuel, which makes hard riding a little tricky!! this only happens after braking hard, at all other times the bike behaves perfectly normaly. please does anybody know the cause of this as its getting frustrating
hesitation after hard braking
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Pete.L
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Gazb&MDJ
It could be either. There is a cbr600 mod which will sort it if it's starvation. Mainly track racing this is required for or it might be because so much fuel is flowing through the carb at high revs the float bowls allow too much fuel past befor they can recover.
I've also had a carb slide sticking open and this gives the same affect or if it only happens around approx 3.5 to 4.5k rpm have you a K&N filter fitted?
Any more info?
Someone here's bound to have an Idea with a few more clues
Pete.l
It could be either. There is a cbr600 mod which will sort it if it's starvation. Mainly track racing this is required for or it might be because so much fuel is flowing through the carb at high revs the float bowls allow too much fuel past befor they can recover.
I've also had a carb slide sticking open and this gives the same affect or if it only happens around approx 3.5 to 4.5k rpm have you a K&N filter fitted?
Any more info?
Someone here's bound to have an Idea with a few more clues
Pete.l
With mine it happens when having braked from 80+ with full on racing gearchanges reving fairly hard (8-10K revs) and then it just doesn't pick back up properly from low/mid range for just a couple of seconds.
This only happens as I say when I'm administering great pain and sufferring to the bike riding very hard and on the brakes so hard the front is squealing as it locks up momentarily and re grips and locks........
eg the kind of braking you do when you realise theres a speed camera too near.....
This only happens as I say when I'm administering great pain and sufferring to the bike riding very hard and on the brakes so hard the front is squealing as it locks up momentarily and re grips and locks........
eg the kind of braking you do when you realise theres a speed camera too near.....
I got knocked down, but i'll get up again and you'll never ever keep me down!
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Pete.L
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Mdj said
Now we all understand 
Are you on std pipes, after market replacement, race pipes? What kind of filter? Is it dyno jetted? ect
Pete.l
Give us all the info you can. I'd hate to say "Hmm,yes. They do that sometimes"
Oh! That kind of breakingthe kind of braking you do when you realise theres a speed camera too near.....
Now we all understand Are you on std pipes, after market replacement, race pipes? What kind of filter? Is it dyno jetted? ect
Pete.l
Give us all the info you can. I'd hate to say "Hmm,yes. They do that sometimes"
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Pete.L
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Mdj,
there are a couple of ways to tackle the problem.
1st you need to ascertain whether the bike is running rich or weak.
The easiest way would be to get it back on the dyno and recreate the problem there. They can monitor the mixture and let you know whats happening.
Or 2nd, you could tape a couple of strips of gaffertape over the air filter inside the air box. This would make the bike run richer. If you make the problem worse then you are probably too rich already, if it improves it you are running slightly lean.
If the stumble does'nt happen with the tape try raising the needles 1/2 or 1 groove if the tape has made the problem worse try lowering by the same amount to weaken the mixture.
Thats all I can think of right now unless someone else has any idea's and here's the link to the fuel pump if nothing else works what have you got to loose. http://www.abercon.co.uk/~neilr/faq_cbr_fpump.htm
Pete.l
there are a couple of ways to tackle the problem.
1st you need to ascertain whether the bike is running rich or weak.
The easiest way would be to get it back on the dyno and recreate the problem there. They can monitor the mixture and let you know whats happening.
Or 2nd, you could tape a couple of strips of gaffertape over the air filter inside the air box. This would make the bike run richer. If you make the problem worse then you are probably too rich already, if it improves it you are running slightly lean.
If the stumble does'nt happen with the tape try raising the needles 1/2 or 1 groove if the tape has made the problem worse try lowering by the same amount to weaken the mixture.
Thats all I can think of right now unless someone else has any idea's and here's the link to the fuel pump if nothing else works what have you got to loose. http://www.abercon.co.uk/~neilr/faq_cbr_fpump.htm
Pete.l
Chaps, this is an easy fix!!
Take the two carb breather pipes out from the brackets either side under the tank and let them hang straight down instead of pointing into the void between the carbs - simple as that!!
You can do it without taking anything off the bike as well so a simple 30 secs to sort.
I had exactly the same symptoms of fuel starvation after heavy braking at donny, this cured it straight away.
Steve
Take the two carb breather pipes out from the brackets either side under the tank and let them hang straight down instead of pointing into the void between the carbs - simple as that!!
You can do it without taking anything off the bike as well so a simple 30 secs to sort.
I had exactly the same symptoms of fuel starvation after heavy braking at donny, this cured it straight away.
Steve
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Pete.L
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Thats right,
Also helps cure if you have been riding hard and then come to a stop ie junction,sheep in the road ect, that pop and stop of the engine
Pete.l
Also helps cure if you have been riding hard and then come to a stop ie junction,sheep in the road ect, that pop and stop of the engine
Pete.l
Last edited by Pete.L on Tue Jun 22, 2004 2:38 pm, edited 1 time in total.
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Stormin Ben
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http://www.abercon.co.uk/vtr1000/displa ... omment=VTR stutters after hard braking
Link to pic to solution to this problem
NB do the rear one too!!
Ben
PS if the links doesn't work, look in the gallery under misc
Link to pic to solution to this problem
NB do the rear one too!!
Ben
PS if the links doesn't work, look in the gallery under misc
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SuperWheelie996
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- Location: Beverly, Ma , US
yep
My superhawk, does the same thing after hard braking and a downshift to 1st gear, it sputters for a moment, then the idle goes back to normal, and it picks back up where it left off
Jason Terry