Starting problems

[baggers]

Well guys, I got my new fuel pump and stuck that it... but now it will start and tick over for a few seconds, then dies, and dies when I open up the throttle, I managed to get it revving a little when I first started it, but now..... crappy. My brother and I took the bottoms of the carbs and gave them a clean before we started it as there was fuel coming out of onr of the carb overflow tubes at first. Sparkplugs changed, could the act of trying to get it going pushed more muck into the carbs? my next plan is to take them off cpmpletely and clean them more thoroughly.. Incidentally, when its on the sidestand and trying to be started fuel still comes out of the left overflow tube, but not when held level. Any advice would be appreciated.

Cheers

[rotortech]

The tank should have been cleaned. If you didn't clean it at least take a light and shine it in there while rocking the bike a little. If there is some cloudy, murky stuff at the bottom you will need to remove the tank, clean it thoroughly, and put a new inline filter on it. If you clean the carbs and keep pumping in dirty fuel you get nowhere.

Carbs - don't just clean the bowls out. You have to remove the carbs and remove every jet. Clean out every jet and passageway with something like old guitar strings. Spray with carb cleaner or brakleen. Keep chemicals off of the diaphrams. Reuse all gaskets and o-rings unless you lose one or find one damaged. They usually work OK. Your description of the cleaning has led me to believe that it was not a thorough job.

[baggers]

Hi there, thanks for the advice mate, As a new pump went in the tank I took the opportunity to clean it out then, So hopefully everything in there is fine, but i think I will use what fuel is left to swill it out again, then disgard the old fuel. The fuel filter is attached to the internal pump. There is no inline filter. I took the carbs off this evening, and checked our earlier handywork, The jets are clean, there is one jet that it does not seem possible to remove though, no hex or place for screwdriver, they are 34mm Keihin CVK carbs. I have not taken the other ends of the carbs apart yet, would you recommend that i do so? Another thought that I had was that perhaps the choke needed adjustment..Its been a while since I tinkered with bikes, so getting used to all the bits again.

[rotortech]

baggers,

I am familiar with Mikuni carbs on FZR600s but I am not familiar with your carbs. I can not recommend any specific instructions for the Keihins.

[yamaha_george]

. Clean out every jet and passageway with something like old guitar strings.

Hi,
When Ro, says guitar strings he does NOT mean the metal variety as these are extremely abrasive & can totally change the jet size re:- gas flow.

See :-
http://www.saltmine.org.uk/martin/jet_sizing.html

to see why the caution as to using Nylon fishing line & guitar strings only

[baggers]

Well, carbs have been off and cleaned.. Still problems, though when we partially covered the airbox, effectivly choking it it started and ran, so im guessing the problem is with the choke, but... On the carbs the choke seems fine and the lever is pulling them on fully.... doh

[baggers]

THe rev counter is going haywire too, could this be a problem with the CDI unit?? It goes up to about 8k RPM, then back to zero in a kind of random pattern..

[DonTZ125]

This is a 'trouble' code being thrown by the TCI (not CDI) box. An 8k code means there is a problem with the fuel low-level light.

[yamaha_george]

This is a 'trouble' code being thrown by the TCI (not CDI) box. An 8k code means there is a problem with the fuel low-level light.

Geez Don where the heck did you find the "trouble code book" that kind of stuff "was eyes only" back in the day

[baggers]

This is a 'trouble' code being thrown by the TCI (not CDI) box. An 8k code means there is a problem with the fuel low-level light.

I guess that won't affect the starting then??

[jallen]

This is a 'trouble' code being thrown by the TCI (not CDI) box. An 8k code means there is a problem with the fuel low-level light.

I guess that won't affect the starting then??

Shouldn't do. I managed to get the error on mine when I didn't plug the pump wiring in correctly.

Interestingly enough (or not). The owners handbook actually mentions the error.

"This model is equipped with a diagnosis device for the fuel sender circuit. If some trouble should occur in the fuel
sender circuit, the tachometer will display a repeated cycle of 0 r/min for 1 second, 8000 r/min for 2 seconds and the
current engine speed for 3 seconds. If this should occur take your motorcycle to a Yamaha dealer for repair."

[apsolus]

my bike does the same thing when i tilt it on the stand i t leaks, when level it doesnt, im thinking our float levels are to high. also your carbs might be out of sync causeing your starting issue

[baggers]

Bike is still not going.... my latest thought is that at some point, the HT leads may have been put on the wrong plugs. The leads are labled 1234 and they have been put on in this order from left to right. I can't get a manual for this bike, is this correct or should they follow the firing pattern of the engine? I don't know what that is, but guess it will be something like 1324? If anyone knows the firing pattern please let me know, and should the lead lables follow this pattern? or simply me numbered from 1 to 4 and run left to right?

Cheers

[jallen]

Bike is still not going.... my latest thought is that at some point, the HT leads may have been put on the wrong plugs. The leads are labled 1234 and they have been put on in this order from left to right. I can't get a manual for this bike, is this correct or should they follow the firing pattern of the engine? I don't know what that is, but guess it will be something like 1324? If anyone knows the firing pattern please let me know, and should the lead lables follow this pattern? or simply me numbered from 1 to 4 and run left to right?

Cheers

Cylinder numbering 1 to 4 from left to right (according to the Thundercat Haynes Manual).

[DonTZ125]

The cyls fire 1243, but the plugs are labeled to make it easy to install - 1234.