nc30 starting problem - update
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nc30 starting problem - update
Right here goes the story, fitted new plugs, changed oil and filter and bike running ok, took off carbs, cleaned them and replaced main jets to (front-120, rear-122), added 0.5mm shim under needles and set air screw to 2.5 turns out. While I was down that far I checked the valve clearances, but decided to leave them until a later date.
Refitted carbs, airbox, new air filter and all relevant pipes, connected petrol tank and tried to start bike to bleed the water system as I had drained the coolant and replaced it with fresh coolant.
The engine turned over but did not start for a while and then it did start but seemed as if it was running on two cylinders. It definately won't start with no choke but needs the choke to be full on.
Any ideas
Refitted carbs, airbox, new air filter and all relevant pipes, connected petrol tank and tried to start bike to bleed the water system as I had drained the coolant and replaced it with fresh coolant.
The engine turned over but did not start for a while and then it did start but seemed as if it was running on two cylinders. It definately won't start with no choke but needs the choke to be full on.
Any ideas

Last edited by brido on Tue Jan 12, 2010 1:27 pm, edited 1 time in total.
- Cammo
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Re: nc30 starting problem
Have you allowed enough time for petrol to fill the float bowls in the carbs? It can take a bit of time normally if the carbs have been drained (if you have the hrc fuel tap mod then they fill instantly).
When the bike is started, there's hardly enough vacuum to open the standard fuel tap to fill the carbs.
Try full choke, NO throttle and keep cranking it over. It may catch on only 1 or 2 cylinders at first, just keep persisting. There's a good chance your battery will die trying to start it from dry. Just hook up jumper leads from a running car and keep trying.
The worst thing you could try in my opinion is to keep opening the throttle or pouring some fuel down its throat.
It will eventually start!
When the bike is started, there's hardly enough vacuum to open the standard fuel tap to fill the carbs.
Try full choke, NO throttle and keep cranking it over. It may catch on only 1 or 2 cylinders at first, just keep persisting. There's a good chance your battery will die trying to start it from dry. Just hook up jumper leads from a running car and keep trying.
The worst thing you could try in my opinion is to keep opening the throttle or pouring some fuel down its throat.
It will eventually start!
"It's just a ride" Bill Hicks
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Re: nc30 starting problem
Thanks for replying tried what you said but now the engine just turns overat least last yesterday it did run a bit. I havn't got the hrc mod done to the fuel tap so how long do I need to turn the engine over for before it will start? I'm afraid of doing some other damage to the starter motor with the prolonged use of it.
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Re: nc30 starting problem
You sure the carbs are on properly? Also, why the larger jets? Is this a race bike?
You can also try some easy start - or carb cleaner sprayed into the carb tops..if it has spark it will give a rumble and might catch enough to get going properly.
You can also try some easy start - or carb cleaner sprayed into the carb tops..if it has spark it will give a rumble and might catch enough to get going properly.
IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
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Re: nc30 starting problem
Sorry forgot to mention, the reason for the larger main jets is because I had fitted a tyga exhaust system, and no its not a race bike and yes I would say the carbs are on properly.
- Cammo
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Re: nc30 starting problem
There's a chance it may be flooded if you've been cracking the throttle while trying to start it (it does sound like you may have killed 'em).
New plugs will have it right if that's the case.
New plugs will have it right if that's the case.
"It's just a ride" Bill Hicks
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Re: nc30 starting problem
Ok I will replace them with the old ones that came out of it, I hope when you say I may have killed them that they are usable once dried out 

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Re: nc30 starting problem
Sometimes they can be revived but not always.brido wrote:I hope when you say I may have killed them that they are usable once dried out
"It's just a ride" Bill Hicks
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Re: nc30 starting problem
ok thanks for the help everyone I will keep you posted on what happens...
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Re: nc30 starting problem
Hi everyone back again with an update on my problem so far, I replaced the plugs with the old ones that came out of it, took the the carbs off again and checked the jets and blew them out with an airline in case of any specs of dirt, everything looked ok, replaced carbs and tried to start it again. Well it fired up and ran for about 5-10 minutes and then because it was so high reving I turned down the idle adjuster(I had moved it when attempting to start it the first time and then lost the setting)and then the engine just dropped away to nothing and it won't start again
. Any help would be great.....
