Loss of power

[jimlad]

Hi all

Just bought an nc30 which suffers from loss of power at random times, the bike in general runs fine then all of a sudden the engine will just die with no warning (when engine die's i dont loose light's or warning light's). If left a minute it will restart and run for anything from 100 yards to 20 miles before it does it again.
I have checked the the battery at startup and underload and its fine, checked earth's , visually checked the loom for any damage.
I'm totally baffled and lost as to what to do next.
Any help or ideas would be greatly appreciated.

Thanks.

[graham72]

Hi all

Just bought an nc30 which suffers from loss of power at random times, the bike in general runs fine then all of a sudden the engine will just die with no warning (when engine die's i dont loose light's or warning light's). If left a minute it will restart and run for anything from 100 yards to 20 miles before it does it again.
I have checked the the battery at startup and underload and its fine, checked earth's , visually checked the loom for any damage.
I'm totally baffled and lost as to what to do next.
Any help or ideas would be greatly appreciated.

Thanks.

Fuel starvation? Check vacuum hose under tank for kinks etc. Fuel tap? Dirty fuel? Rust in tank?
Could be a carb problem, take out clean up insides and replace.
Degraded spark plugs? Try new plugs, does it only happen when bike is at normal running temp?
You say you checked the battery, I take you mean with a multimeter?
Checked oil level?

Was this reason the seller was selling?

Graham

[jimlad]

Hi graham

Yes battery checked with mutimeter, i fitted a new vacuum pipe as at first i thought it was fuel related but the loss of power is instant there is no warning its like the kill switch has been hit, sometimes it can be revving at say 12-13000 rpm then all of a sudden its dead the needle will just drop to say 3000 rpm and then it will pick up again and be ok and run fine for maybe an hour or so.Will get the carbs of and give them a good clean, the problem is very random could happen when been out on the bike 2 mins or it could take an hour.will try with another set of plugs.

Thanks graham.

[Dgeoff33]

Jim, did you get it from Conisborough?

[SouL]

I had the same problem...I seemed to have sorted it out. Have you fitted a fuel filter to your bike? If so take it out, get yourself a new piece of fuel hose and cut it to fit exactly from your fuel tap hose to where it splits at the "T" into your cabs. Sounds like you have fuel starvation and will find that it happens generally when your tank is half empty. My bet is that you having the same problem as me and your bike is creating a air lock and having a fuel filter just cause more cr4p!

Check out my post
viewtopic.php?f=22&t=20298

[Neosophist]

Hi graham

Yes battery checked with mutimeter, i fitted a new vacuum pipe as at first i thought it was fuel related but the loss of power is instant there is no warning its like the kill switch has been hit, sometimes it can be revving at say 12-13000 rpm then all of a sudden its dead the needle will just drop to say 3000 rpm and then it will pick up again and be ok and run fine for maybe an hour or so.Will get the carbs of and give them a good clean, the problem is very random could happen when been out on the bike 2 mins or it could take an hour.will try with another set of plugs.

Thanks graham.

Give it a usual service first to elimate any of the usual suspects,

Plugs / air filter.

May as well clean carbs / check & set valve clearances and balance the carbs / replace oil and plugs. if you dont know when they were last done, will save you doing the job twice.

Charging systems are weak on these bikes so fully inspect the battery and genny voltages and look for signs of melted reg/rec plugs.

could be a dodgy earth / wire thats loose...

The main fuse in one of my bikes has a snapped blade that kept comming loose, caused all sorts of electrical / loss of power erratic behaviour and was a buggar to track down.

[jimlad]

Hi

Yes it's the one from conisborough geoff

No fuel filter on the bike but will thoroughly check fuel line, thanks soul

Will give bike a service, i just had a quick look at reg/rec and its had a fault at some point as the plug on the loom side has some heat damage, thanks neo

Jim.

[Neosophist]

Ah the genny plug.

These often melt, sometimes it's just becuase the connectors get dirty and oxidise, this plug carries a high current and if the contacts get dirty it creates extra resistance which causes the plug to burn.

Also an aging battery will help push a reg-rec over the edge, the r/r unit has poor cooling for large loads, an older battery can't take as much charge as a new one so the r/r burns the extra off as heat, this is easy enough to kill a reg/rec.

You'll get it sorted :)

[jimlad]

I know its been a while but this may help somebody.
In the end it was a faulty CDI.