could this be electrical or is it fueling??????????

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dave_c24
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could this be electrical or is it fueling??????????

Post by dave_c24 »

hi,

my bike hesitates around 10-11k in every gear,not very noticble in lower gears but getting more and more as you go through 3rd 4th and 5th. it will pull harder and harder till just before 10k then the pull doesnt seem to increase till just after 11k and its like a switch is flicked and takes off?!?

revs clean as a wistle in neutral!!

it is worse at full throttle a slightly more gradual throttle improves things.but gets worse when the bike nears reserve? which may be in tank filter, this was clean around a month ago.

the bike had the prob from the start but since then i have changed carbs, inlet rubbers and clips, plugs, throttle cables, choke cable,balanced carbs,checked float heights, checked choke operation, float valves are sealing. emulsion tubes are correct, old carbs ran 115 jets allround, new ones run 112 front 115 rear.air filter is clean

previose carbs were shot and bike would not tick over properly and had the flatspot described. now new carbs etc are on and airleaks are cured im still having the poblem which make me wonder if it may be electrical??

help me cure it please

cheers dave
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Re: could this be electrical or is it fueling??????????

Post by wullvfr »

usually electrical issues are temperamental,whereas fuelling issues tend to happen all the time.

so i would be inclined to say the problem lies with the carbs in one way or another.




wull
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RonniB
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Re: could this be electrical or is it fueling??????????

Post by RonniB »

fuelling, sound like it's to rich on the main jet, is it restricted??
greggo
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Re: could this be electrical or is it fueling??????????

Post by greggo »

Check fuel flow, disconnect the hose from the tap and turn the tap on, it should pour out. if thats okay, check there is a good flow of fuel on the carb side of the fuel filter, if it hasn't had a filter change since Mr Honda birthed it....it'll be dirty.
dave_c24
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Re: could this be electrical or is it fueling??????????

Post by dave_c24 »

cheers for replys guys, that confirms my fears, carbs off again!!! :evil: gota b the 6th time in 2 months!!

i might try fitting my mate nc30 carbs if theyve got to come off and give them a go.

i will check the filter and fuel flow 1st though,but seems strange its only at 10-11k nowhere else.i did check flow around a month ago when fitted filter in tank but wont hurt to check again!

i dont really understand carbs to the full.

cheers Dave
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Re: could this be electrical or is it fueling??????????

Post by superlite »

I wouldn't think it was the fuel filter if you've replaced it. Have you checked main jets, pilot jets and needles for fuel varnish? NC24s are at that age when they seem to have loads if the carbs have sat idle. What's your airbox/filter set-up? Standard? I'd personally strip the carbs and clean and check everything.
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dave_c24
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Re: could this be electrical or is it fueling??????????

Post by dave_c24 »

superlite wrote:I wouldn't think it was the fuel filter if you've replaced it. Have you checked main jets, pilot jets and needles for fuel varnish? NC24s are at that age when they seem to have loads if the carbs have sat idle. What's your airbox/filter set-up? Standard? I'd personally strip the carbs and clean and check everything.
main jets and pilot jets are all good, only put carbs on bike friday last week. they are ny second set and still same problem but atleast my starting/tick over problem is gone :grin: .

airbox and filter are standard.no cracks etc, old box was damaged so replaced it.

cheers dave
jamie
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Re: could this be electrical or is it fueling??????????

Post by jamie »

Hmmmmm strange i have the same problem but at a different range mine happens between 5k and 7k revs where it just dies i have been told it is probably a fuel/air mixture problem and the carbs most probably need to come off, but thought i would try and prove everything electrical first i have just tested my ignition coils and the front coil resistance on the secondary winding with the caps on reads 37k ohms and the tollerance according to the hanes manual is 14k to 25k so im going to try changing that first im not convinced but it can only do it good changing it ill let you know how it goes,
hope you get it sorted soon.
Jamie
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Re: could this be electrical or is it fueling??????????

Post by dave_c24 »

jamie wrote:Hmmmmm strange i have the same problem but at a different range mine happens between 5k and 7k revs where it just dies i have been told it is probably a fuel/air mixture problem and the carbs most probably need to come off, but thought i would try and prove everything electrical first i have just tested my ignition coils and the front coil resistance on the secondary winding with the caps on reads 37k ohms and the tollerance according to the hanes manual is 14k to 25k so im going to try changing that first im not convinced but it can only do it good changing it ill let you know how it goes,
hope you get it sorted soon.
Jamie
do you have a test method that i can try, dont know much about electrics :oops:

cheers dave
jamie
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Re: could this be electrical or is it fueling??????????

Post by jamie »

Hi Dave
Like i said im not convinced it is this but if you want to test it all you need to do is get yourself a multi meter and set it to ohms, it might have different ranges on it so you will need to switch it to a range where you can measure up to the specified ohms for the test you are doing, you will find the values at the start of the ignition section in the Hanes manual. If its like mine you wont have all the different settings just the selection for ohms.
The ignition coil has 2 sets of windings. The primary, which is where the 2 wires connect and the secondary, which is the side where your spark plug caps (red leads) come off.
There are 3 tests you can do to determine if there is a fault

1. Disconnect the 2 wires on the primary side and put your meter probes on the contacts of the ignition coil. You will now have an ohms reading on your meter, Should be within 2.5 - 3.5 ohms. This test will prove your primary windings are ok.

2. Pull the caps off your spark plugs and put one probe down one cap and the other probe down the other so you are measuring from the cap end down the lead, through the secondary windings and back up the other lead. The contacts are quite far down the spark plug caps so make sure you push your probes in well. You should have a reading on your meter, the tolerance for this is around 14k - 25k ohms. This test proves your secondary windings and your plug caps and leads.

If this test failed you will need to do the next one to determine weather its your leads or secondary windings that are at fault, if it was within tolerence you wont need to do the next test and you will have a healthy ignition coil and leads.

3. Disconnect the red leads from the coil pack and put your meter probes accross the secondary windings, again the contacts are quite far down. It should read within 11k - 14k ohms. If the ohms reading is within tolerance that would suggest your leads are at fault and obviously if the readings are out your coil is faulty

hope this helps

Jamie
Last edited by jamie on Fri Jun 12, 2009 8:59 pm, edited 1 time in total.

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