stuttering on acceleration
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stevepaff
- Settled in member
- Posts: 12
- Joined: Fri May 09, 2008 2:10 pm
stuttering on acceleration
Hi Guys n gals
for want of a better word stuttering is all I can think to describe it.
My poor little nc30 has developed a bit of an issue it never seemed to have before.
A short while ago after a prolonged steady speed at 50mph through roadworks I reached the end of them and opened the throttle, usually the bike picks up nicely and just goes. Now this particular time it decided to hold back and stutter a bit before it cleared itself and pulled away. After that every time I let off the throttle and reopened it the stutter was still evident.
I got off the motorway and when trying to pull away from the junction it really bogged down and almost stalled, slipped the clutch a bit longer than normal and it managed to pull away. had a nice twisty varied throttle road after that and by the time I'd done 5 mins of that it was happy again and rode like it always used to.
Has anyone any ideas on what might be happening and what I could check.
Bit of info on the bike incase its needed....
1994 NC30
Speed limiter removed at speedo end (removed the tab inside ages ago)
Unknown full stainless system with carbon can (imported with that installed)
Unknown if any jetting was done
Fully serviced recently and valve clearances read within tolerance
Fuel tap modified (but was done a good few years ago with no ill effects)
plug gaps all correct
Don't think the plug leads would be causing an issue as I'd imagine the problem would be there all the time if they were breaking down.
Oh and I'm going to be balancing the carbs for good measure as soon as I get some new hose for the guages.
I think its protesting about not being used as much as it wanted last year.
Cheers
Paff
for want of a better word stuttering is all I can think to describe it.
My poor little nc30 has developed a bit of an issue it never seemed to have before.
A short while ago after a prolonged steady speed at 50mph through roadworks I reached the end of them and opened the throttle, usually the bike picks up nicely and just goes. Now this particular time it decided to hold back and stutter a bit before it cleared itself and pulled away. After that every time I let off the throttle and reopened it the stutter was still evident.
I got off the motorway and when trying to pull away from the junction it really bogged down and almost stalled, slipped the clutch a bit longer than normal and it managed to pull away. had a nice twisty varied throttle road after that and by the time I'd done 5 mins of that it was happy again and rode like it always used to.
Has anyone any ideas on what might be happening and what I could check.
Bit of info on the bike incase its needed....
1994 NC30
Speed limiter removed at speedo end (removed the tab inside ages ago)
Unknown full stainless system with carbon can (imported with that installed)
Unknown if any jetting was done
Fully serviced recently and valve clearances read within tolerance
Fuel tap modified (but was done a good few years ago with no ill effects)
plug gaps all correct
Don't think the plug leads would be causing an issue as I'd imagine the problem would be there all the time if they were breaking down.
Oh and I'm going to be balancing the carbs for good measure as soon as I get some new hose for the guages.
I think its protesting about not being used as much as it wanted last year.
Cheers
Paff
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Cammo
- Site Supporter
- Posts: 4505
- Joined: Thu May 01, 2008 12:35 am
- Bike owned: NC30
- Location: Melbourne, Australia
Re: stuttering on acceleration
Do you have a haynes manual?
First thing I'd be suspecting is the charging system. Check the regulator/rectifier and the alternator, they play silly buggers on these bikes and can cause symptoms like yours.
Check that the battery voltage is 13.5-14.4v at idle, low and mid revs. Also look at the condition of the reg/rec plug, connectors and the wiring for an signs of burning.
First thing I'd be suspecting is the charging system. Check the regulator/rectifier and the alternator, they play silly buggers on these bikes and can cause symptoms like yours.
Check that the battery voltage is 13.5-14.4v at idle, low and mid revs. Also look at the condition of the reg/rec plug, connectors and the wiring for an signs of burning.
"It's just a ride" Bill Hicks
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stevepaff
- Settled in member
- Posts: 12
- Joined: Fri May 09, 2008 2:10 pm
Re: stuttering on acceleration
Yep got a Haynes, first thing I get whenever I get any vehicle.
I'll have a look at those suggestions, can't imagine it being the Reg as I changed that a little while back last time it fried.
Def worth a check tho. won't even need to take the fairing off to check the voltage either as I adapeted it many moons ago for chargers and this actual reason :)
meant to be rebuilding my car and riding the bike not the other way round, sod's law hey :)
I'll have a look at those suggestions, can't imagine it being the Reg as I changed that a little while back last time it fried.
Def worth a check tho. won't even need to take the fairing off to check the voltage either as I adapeted it many moons ago for chargers and this actual reason :)
meant to be rebuilding my car and riding the bike not the other way round, sod's law hey :)
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wullvfr
- Site Supporter
- Posts: 1027
- Joined: Wed Apr 30, 2008 8:40 pm
- Bike owned: zx9r c1
- Location: killin,scotland
Re: stuttering on acceleration
i wouldn't think it was anything to do with the reg rec but do a simple charge rate test at the battery just to rule that one out.
i would double check how well each spark plug is sparking,check all connections at leads and coils,check cdi connections as well.
to me it possibly sounds carb related,next time it happens put the choke on and see what happens.if it is fuel related then this helps determine if the bike is running rich or lean.if putting the choke helps it clear then you know its running lean when it bogs down and vice versa.if it was to do with the exhaust system and not being re-jetted then i think you would have had issues before but its maybe worthwhile stripping the carbs down and seeing what size jets are fitted,and giving them a wee clean whilst you are at it.
william
i would double check how well each spark plug is sparking,check all connections at leads and coils,check cdi connections as well.
to me it possibly sounds carb related,next time it happens put the choke on and see what happens.if it is fuel related then this helps determine if the bike is running rich or lean.if putting the choke helps it clear then you know its running lean when it bogs down and vice versa.if it was to do with the exhaust system and not being re-jetted then i think you would have had issues before but its maybe worthwhile stripping the carbs down and seeing what size jets are fitted,and giving them a wee clean whilst you are at it.
william
please,god,....give me the chance to prove that winning the lottery won't spoil me!!!
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stevepaff
- Settled in member
- Posts: 12
- Joined: Fri May 09, 2008 2:10 pm
Re: stuttering on acceleration
Cheers for the suggestions guys.
Checked the voltages and as suspected everything was fine there.
Decided to strip and clean the carbs for good measure, all seemed clean with no blockages.
Could see some nunmbers on the needles.
one pair had J51A and the other pair had J51B Just wondered what they mean.
Getting my carb balancer back tomorrow and will balance them up for good measure, been so long since I used the balancer all the pipes had perished lol.
All plugs were sparking nicely and I reseated all connections all seemed fine.
once I rebuild it I'll take it for a spn and see if the problem still exists. if its still there I'll try the choke method.
Checked the voltages and as suspected everything was fine there.
Decided to strip and clean the carbs for good measure, all seemed clean with no blockages.
Could see some nunmbers on the needles.
one pair had J51A and the other pair had J51B Just wondered what they mean.
Getting my carb balancer back tomorrow and will balance them up for good measure, been so long since I used the balancer all the pipes had perished lol.
All plugs were sparking nicely and I reseated all connections all seemed fine.
once I rebuild it I'll take it for a spn and see if the problem still exists. if its still there I'll try the choke method.
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stevepaff
- Settled in member
- Posts: 12
- Joined: Fri May 09, 2008 2:10 pm
Re: stuttering on acceleration
Actually don't worry about what the numbers mean, just did a quick search and answered it myself :)
One thing I did notice actually was one of the pilot screws was almost half a turn out from the others, rekon that might cause me a problem, if so its easy enough to change :)
One thing I did notice actually was one of the pilot screws was almost half a turn out from the others, rekon that might cause me a problem, if so its easy enough to change :)