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nc30 throttle responce

Posted: Thu Sep 29, 2011 12:07 pm
by quinn12
Hi guys

I want to know what you think.

1. When I start my bike up with choke and no throttle she starts once off no problems, I would let her idle like that for a wile and then close the choke, here is the thing, when I open the throttle just a bit or alot it sound like the enjine want to die, close the throttle and open it up again she will rev till between 5 and 8k rpm,

2. with clutch pulled she will rev to 14 easely but not when I am in gear and riding. Could this be carb sync? I have km\h clocks on so dont think there is restrictions on the clocks.

pls help.

Thanks

Re: nc30 throttle responce

Posted: Thu Sep 29, 2011 1:02 pm
by Hadies
Can't suggest anything other than don't rev your bike to 14k rpm with the clutch pulled in!!

Re: nc30 throttle responce

Posted: Thu Sep 29, 2011 2:30 pm
by quinn12
I was just testing to see if it would go past 10k rpm.

Re: nc30 throttle responce

Posted: Thu Sep 29, 2011 2:34 pm
by quinn12
tis not like I cranked it upand kept it there. :grin:

Re: nc30 throttle responce

Posted: Thu Sep 29, 2011 3:47 pm
by amaechizzle
Is this when the bike is cold?
From what I know, They hate being cold.

Whats it like when your riding it?

Re: nc30 throttle responce

Posted: Fri Sep 30, 2011 8:05 am
by quinn12
Well.
When she is cold she only rev to 5k maybe 6k, so I usualy take it very slow and easy on her when I start off riding, wait untill the temp meter is between 70 and 90 before I will start pushing her a bit harder. I was riding on the high way the otherday and the moment I go up hill -not very steap- she would lose power, the revs would drop from 8k to round 5k, have to gear down and open her up to maintain a desent speed -110km\h-.

I took her out last night, started her up and let her idle for about 5 min, I sprayed some water on the front exhaust pipes and it evaporated on contact but the back one`s stayed for longer, I then took her for a 20min ride and when I came back i did the water test again and it evaporated on contact on all four exhausts. Again on the ride again she would start splatter at round 8k rpm but would go to 10k rpm with a lot of splatter. and no power.

Re: nc30 throttle responce

Posted: Fri Sep 30, 2011 4:16 pm
by amaechizzle
Any smoke coming out of the exhaust?
I would also suggest, pulling out your spark plugs and having a look to see what colour they are.
If there is black smoke, would suggest a break down in spark, or to much fuel.
No smoke and white plugs would suggests no fuel.

Re: nc30 throttle responce

Posted: Mon Oct 03, 2011 2:18 pm
by quinn12
Hi,

Thanks for the reply

I dont see exesive smoke when I start the bike, I will check the plugs tonight and see if the are ok.

I did opended the carbs up again and drilled the 2.5mm hole for throttle responce and put in a nother .5mm washer on each needle but all still seems the same with the bike, also now when I ride and she gets warm the idle speed picks up, whe I start the bike with full choke, let the bike warm up and close the choke it would rev round 1.5k rpm, after 5 min of riding the bike would rev at round 4k rpm. I the set the idle screw back to 1.5k rpm but after a nother 5min ride its back on 4k rpm. What could cause that? Still when I open the throttle a bit quick its almost like it floods, or starving for fuel, if i play it slow the bike revs up a bit and the I can open the throttle with out the bike sounds like it wants to die.
I seriously dont know what to try next or what to look for.

please help...

Re: nc30 throttle responce

Posted: Mon Oct 03, 2011 3:22 pm
by Neosophist
It sounds like you have an air-leak on the carb rubbers, this will cause the high idle speed.

It's also possible but unlikey that your throttle cables / choke is sticking.

When you turn the idle down is it smooth or lumpy?

Spray carb cleaner around the carb rubbers with the engine running and listen out for changes in RPM. This indicates and air-leak.

Never rev the engine past 10k in neutral as it can cause mechanical failures as there is less tension on the internal components.

Even from cold, you should be able to run it to the red-line in gears.. might be a bit lumpy until warm.

How are your carbs setup? what jets, everything clean? needles in the right place?

If it dosn't want to rev under-load somethings not right somewhere

Re: nc30 throttle responce

Posted: Tue Oct 04, 2011 8:19 am
by quinn12
hi

the idleing is lumpy, I will check tonight if the carb are on proprely, when I put them on it feel like somethinfg sits in the middle of the carbs, when I have the back right hand side in there is a gap by the back lefthand side on, then when I press down on left hand side the right hand side lifts out again, I have checked under it but can see anyhing that it in the way.

ok I understand the part of not reving it hight with clutch in, but why will it rev like that with clutch in an not when riding... just doesnt make sence to me - thats probably why I am not a mechanic - lol