Idle issue, battery dying.
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- Settled in member
- Posts: 7
- Joined: Mon Mar 11, 2013 1:35 am
- Bike owned: Honda RVF400 - NC35
- Location: Seaford
Idle issue, battery dying.
Just got myself a NC35, first motorbike ive worked on (being a V4, supposedly not the easiest to start with, but i like the deep end of the pool) When the chap bought it along, it started first time, no hassle, idle sat at 2-2.5k revs and it warmed up quickly.
Fast forward to the next day (after purchase) go to start it and its a dead battery, i put it down to being on idle for about an hour the day before while checking it over, so i recharged it, and it started first time, although, ive got another issue, the revs seem to drop from 2.5k slowly down and the engine shuts off. So far the only solution ive found it to give it some constant throttle (4k or so) for a few minutes and the idle is fine after that...any suggestions?
Ive worked on cars...but bikes are new to me, so be gentle please
Fast forward to the next day (after purchase) go to start it and its a dead battery, i put it down to being on idle for about an hour the day before while checking it over, so i recharged it, and it started first time, although, ive got another issue, the revs seem to drop from 2.5k slowly down and the engine shuts off. So far the only solution ive found it to give it some constant throttle (4k or so) for a few minutes and the idle is fine after that...any suggestions?
Ive worked on cars...but bikes are new to me, so be gentle please

- bikemonkey
- NWAA Supporter
- Posts: 1524
- Joined: Tue Dec 27, 2011 12:33 pm
- Bike owned: 92 NC30, 90 VFR750
- Location: Oxfordshire
Re: Idle issue, battery dying.
What does the bike idle at normally?
Should be 1.3k rpm.
Most likely your carbs are to blame for the idle.
As for the battery you could have a fucked battery, drain in the wiring loom, bad earth, knackered charging system. Who knows. Could also just be the fact that when the NC35's ignition is on the low beams are also, which would drain the battery when just sitting at idle.
First thing to check is the voltage across your battery when the bike is off after a full charge.
Should be 1.3k rpm.
Most likely your carbs are to blame for the idle.
As for the battery you could have a fucked battery, drain in the wiring loom, bad earth, knackered charging system. Who knows. Could also just be the fact that when the NC35's ignition is on the low beams are also, which would drain the battery when just sitting at idle.
First thing to check is the voltage across your battery when the bike is off after a full charge.
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- Settled in member
- Posts: 7
- Joined: Mon Mar 11, 2013 1:35 am
- Bike owned: Honda RVF400 - NC35
- Location: Seaford
Re: Idle issue, battery dying.
When i bought the bike, it had a recent service (a week prior) which had all the carbs cleaned and balanced etc.
Its a pretty new battery in there, i found with the idle adjuster it seems to keep rom dropping to zero and shutting off...can that happen if the idle adjuster is turned low enough?
Ill get a multi-meter and check the loom across sometime this week
Its a pretty new battery in there, i found with the idle adjuster it seems to keep rom dropping to zero and shutting off...can that happen if the idle adjuster is turned low enough?
Ill get a multi-meter and check the loom across sometime this week
- Cammo
- Site Supporter
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- Joined: Thu May 01, 2008 12:35 am
- Bike owned: NC30
- Location: Melbourne, Australia
Re: Idle issue, battery dying.
Are you using the choke when you start it?
Correct starting procedure from cold is FULL choke, NO throttle.
After a few minutes or so of full choke you should be able to shut it off and the bike will hold idle. If not something is up.
Correct starting procedure from cold is FULL choke, NO throttle.
After a few minutes or so of full choke you should be able to shut it off and the bike will hold idle. If not something is up.
"It's just a ride" Bill Hicks
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- Settled in member
- Posts: 7
- Joined: Mon Mar 11, 2013 1:35 am
- Bike owned: Honda RVF400 - NC35
- Location: Seaford
Re: Idle issue, battery dying.
Thanks cammo! lifesaver. heres what i did :
Started with no choke : starts straight to 2k revs, drops to zero and cuts out.
Started with choke : Straight to 2k revs and drops to 1.5k and sits there no problems...
Why must i be so stupid, my bloody VW mk1 caddy has a choke and that doesnt start in the cold without it on haha! Problem averted and lesson learnt!
Started with no choke : starts straight to 2k revs, drops to zero and cuts out.
Started with choke : Straight to 2k revs and drops to 1.5k and sits there no problems...
Why must i be so stupid, my bloody VW mk1 caddy has a choke and that doesnt start in the cold without it on haha! Problem averted and lesson learnt!