View Full Version : I shimmed the needles and.... :(


Gbug
January 24th, 2009, 05:40 PM
Okay, so yesterday I tore down the bike and put two 4mm washers under each needle. Started the bike up on the stands, immediately noticed a difference. The bike didn't want to die when I first twisted the throttle, which it usually does. Let it idle for about 5 mins, also revved it up to about 6-8k, no problems whatesover. Took it off the stands and rode it around the parking lot for 30 seconds. When I coasted up in N to park the bike, it died on me. Never done that, but I didn't really think anything of it.

Today I put the bike all back together and was going to go for a ride, but it wouldn't start. Tried choke, no choke, some choke, full throttle, no throttle, nothing worked. It is 35 degress outside, but it has always started up when it is in the 40s. I'm running the stock exhaust, desnorkled. What do you think the deal is?

kkim
January 24th, 2009, 05:51 PM
Grant... try adjusting the idle speed control knob on the left hand side of the bike right below the black side panel. Turn it clockwise (I think) to increase the idle speed. (about 1/2 turn for now)

It might be set too low right now, but that should not prevent the bike from starting. Are you sure you reattached both the fuel and vacuum hoses to the fuel petcock?

As a side note, when Viper byte used 4mm washers, his bike ran like crap after he put it back together and he had to replace the 4mm washers w/ 3mm washers for it to run properly, but that is another problem entirely from what you're seeing. Just thought I'd mention that for now.

kkim
January 24th, 2009, 06:07 PM
Couple of other thoughts... are you sure you have enough fuel in the tank? and if all else fails, try putting the petcock into the prime position to make sure you are getting gas to the carbs. It sounds like a fuel delivery problem.

Viper-Byte
January 24th, 2009, 06:09 PM
When you try to start it, does it try to start?

It is also possible that the engine has become flooded.

I would suggest you take the needles out and check that the washers are fitting inside the spring mechanism properly. My issue was with the 4mm washers being too big to fit in the spring mechanism, the needle was able to move up and down (should not happen like this), idle was fine, but when reved about 3krpm, it just died.

Gbug
January 24th, 2009, 08:26 PM
Couple of other thoughts... are you sure you have enough fuel in the tank? and if all else fails, try putting the petcock into the prime position to make sure you are getting gas to the carbs. It sounds like a fuel delivery problem.

Tank is full. I'm a noob, please explain what the prime position is. I know where it is on the petcock, just don't know what it does.

I would suggest you take the needles out and check that the washers are fitting inside the spring mechanism properly. My issue was with the 4mm washers being too big to fit in the spring mechanism, the needle was able to move up and down (should not happen like this), idle was fine, but when reved about 3krpm, it just died.

I'm going to pull the needles tomorrow and replace with 3mm.


The weird thing is, it idled perfect yesterday for a full 5 min after I shimmed the needles. Revved up great too. If it died the night before because it flooded, shouldn't I still have been able to start it this afternoon?

kkim
January 24th, 2009, 08:43 PM
prime position is to let fuel flow even if no vacuum is present, like after you've worked on the carbs and the float bowls may be empty. just don't forget to put it back to the on position once the bike gets started.

yeah, the fact that it started, says it has the parts back together so it should run. That it does not now, makes me think the carbs have run out of gas and needs more.

what happens exactly when you hit the start button? does the engine turnover? If so, turn off the choke, hold the throttle wide open and crank the bike for about 10 seconds. If it's flooded, this should clear it out enough to get it started.

are you sure that you put the vacuum hose back on the petcock?

Gbug
January 24th, 2009, 09:08 PM
I have feeling that I may have misplaced a hose. I was a little uneasy when replacing them, and I wasn't sure if they were going in the right places. I ended up having to disconnect 3 or 4 hoses. The last one I reconnected plugged into the black thingamabobber next to the fuel petcock. I've been trying to find more pictures showing hoses but no dice.

kkim
January 24th, 2009, 09:17 PM
this help? make sure the hose marked in orange is connected correctly. kinda ignore the rest as this is for a cali model.

http://faq.ninja250.org/images/d/d8/Routing.gif

g21-30
January 25th, 2009, 09:20 AM
Since the bike started/idled, etc. after you put the carbs back together, it sounds like you have a fuel flow problem. As kkim stated, put the fuel valve in the "PRI" position. If the bike starts, then you have have a vacuum hose problem. The bike was running off the fuel left in the bowls. In order for the bike to start, you need 3 things: gas, air, and ignition. If you're alive (breathing), then it has air. You didn't touch the spark plugs (did you remove the plug wires?). The only thing left is gas.

:)

Gbug
January 25th, 2009, 12:40 PM
Problem solved! Turns out it was a pinched fuel line. When I routed the line to the petcock, it somehow got folded up on itself and fuel wasn't getting through.

Viper-Byte
January 25th, 2009, 12:45 PM
Good to hear you got it sorted :thumbup:

kkim
January 25th, 2009, 03:50 PM
great! :thumbup:

how does the bike run with the shims?:)

Gbug
January 25th, 2009, 09:14 PM
Ehh, too soon really to tell. I have noticed that it doesn't take as long to warm up. I only had about 500 miles with the stock needles, so it is kind of hard for me to be able to tell a huge difference right away. I ended up staying with the 4mm washers.