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RVF400 NC35 ongoing problem

Posted: Fri May 17, 2019 2:00 pm
by Travis
Hello,

I need some advise please. I have a RVF 400 that I have built up from a junkyard project.

I cannot get this thing to start.

Some background:
  • New Plugs
    Freshly rebuilt carbs - bench tested float valves, all working as they should
    Standard exhaust and intake, and standard carb jetting
    Checked compression - its good
    Check spark and there is spark - i remove the plug and leave it on the wire, it sparks when against the frame
It will NOT fire up, it will just turn and turn and turn and make ZERO attempt to start.

I confirmed via drain screw that the carbs are getting fuel (all 4 of them).

All I can think to do is check ignition timing is correct?

Any advise, this is a two year long project, and the bike looks spectacular, I just cant get it to fire up.

Thanks!!!

Re: RVF400 NC35 ongoing problem

Posted: Fri May 17, 2019 2:20 pm
by Speedy
Sounds like something is cutting off the ignition.
Check switch connections are as they should be; side stand and/or kill switch?

Re: RVF400 NC35 ongoing problem

Posted: Fri May 17, 2019 2:31 pm
by Travis
Speedy wrote:
Fri May 17, 2019 2:20 pm
Sounds like something is cutting off the ignition.
Check switch connections are as they should be; side stand and/or kill switch?
Side stand and kill switch would cut spark, I have spark though? just no ignition which is driving me mad.

Re: RVF400 NC35 ongoing problem

Posted: Fri May 17, 2019 6:25 pm
by Suzuki416
are you pulling in the clutch & is it in neutral?

Re: RVF400 NC35 ongoing problem

Posted: Mon May 20, 2019 12:32 pm
by Travis
Suzuki416 wrote:
Fri May 17, 2019 6:25 pm
are you pulling in the clutch & is it in neutral?
Hi, thanks, yes I am,these things would cause the system to cut spark, the bike has spark albeit a weak looking little spark.

If I pull a plug wire and put a plug on it, against the frame, it sparks.

I have spark, have fuel, I have compression, it just doesnt go boom

Re: RVF400 NC35 ongoing problem

Posted: Mon May 20, 2019 1:33 pm
by gavins
What's your battery voltage look like? Try another battery or better yet jump it off a car battery?

Have the valve clearances been checked?

Re: RVF400 NC35 ongoing problem

Posted: Mon May 20, 2019 2:09 pm
by Travis
gavins wrote:
Mon May 20, 2019 1:33 pm
What's your battery voltage look like? Try another battery or better yet jump it off a car battery?

Have the valve clearances been checked?
battery about 18 months old, fully charged though overnight before I tried to start it the last time, the motor turns happily on the starter for quite a while before it gets run down. clearances are set within spec by myself

Re: RVF400 NC35 ongoing problem

Posted: Tue May 21, 2019 2:26 pm
by Speedy
Travis wrote:
Fri May 17, 2019 2:31 pm

Side stand and kill switch would cut spark, I have spark though? just no ignition which is driving me mad.
The kill switch kills the ignition; I believe the side stand switch does the same.
When the kill switch is on the 'Off' position, the starter motor will still work, but the engine won't fire up.
I'm assuming you have the kill switch on the 'Run' position, (you wouldn't be the first ;) ) so maybe check the wiring, connector and the switch itself too; it's worth checking the clutch switch as well.

Re: RVF400 NC35 ongoing problem

Posted: Tue May 21, 2019 7:47 pm
by batchelor
Did you fit new plugs?

I had a problem on my NC30 where it would only fire on 1 or 2.
All plugs sparked when checked against frame.

Turns out the plugs were weak. New set fitted problem solved.

Plugs are not cheap and watch out for fake ones on ebay.

Re: RVF400 NC35 ongoing problem

Posted: Wed May 22, 2019 11:20 am
by Travis
batchelor wrote:
Tue May 21, 2019 7:47 pm
Did you fit new plugs?

I had a problem on my NC30 where it would only fire on 1 or 2.
All plugs sparked when checked against frame.

Turns out the plugs were weak. New set fitted problem solved.

Plugs are not cheap and watch out for fake ones on ebay.
This is my last resort, these dam plugs cost a fortune, ZAR1000 for a set of 4. Im tempted to take the known working plugs out of my VFR and stick them in the RVF and see if it changes things? its good to know you tested them and they sparked, as mine also do, but then when you used new ones it worked. perhaps the plugs are fouled and dont spark enough? I always thought that spark is spark, perhaps it needs a really strong spark to ignite. thanks :)