NC29 still not working! need help ASAP!

[1308lee]

hi the bikes still not working, theres 2 pipes under the tank that dont appear to connect to anything? theyre inbetween the first 2 and last 2 carbs

(CARB) (pipe) (CARB) (CARB) (pipe) (CARB)


does anyone know what these are?

[1308lee]

ok i think theyre just breathers it shows them like that in a pic in the service manual...

what the problem is, is the bike starts fine, revs up in neutral a little slow but still revs, but when i set off theres no power what so ever... and i dont mean less power, i mean, struggling to hit 30mph in 1st full throttle? replaced coils and CDI unit? does anyone have any suggestions AT ALL as to what it can be?

[petrolhead19]

Yes they are breathers from the carbs.

Sounds silly but check your ignition fuse and the connecting points for the fuse give them a good clean, also check your fuel pump is working just get 2 pieces of wire and put it straight to the battery see if it works, also check your fuel pump relay.

Adam

[gullarm]

The two out ones are breather pipes for the fuel, the middle one is an air tube for the slides in the carbs

RIGHT.....................

Do all 4 exhausts get hot on tickover? I mean hot not warm. Spray them with water to check!

Is it banging and farting out the exhaust.

Is the exhaust blocked?

Does the exhaust smell of fuel?

Did you wire up the coils backwards - get two of them on the wrong cylinders? Easily done!

Does each lead spark when cranking over - I had one plug lead faulty, one end cap open circuit and one plug open circuit. So only fired on one cylinder.

Get all plugs out and crank the engine with all the plugs on the engine block and see if they all spark, I used a bungee cord to tie em down to the frame.

Are the plugs new - are they fouled - you cant clean them - just bin em if they look fecked.

Have you got around 13V when runnning and rising to 14V when revved.

Are the batt terminals tight and corrosion free - trace the cable to the starter solenoid as well - is that a good connection.

Is the batt good - keep it on charge.

Is the fuel tap flowing fuel freely?

Is there a air lock in the fuel tank - try with the cap open?

Are the float bowls full of fuel - turn off the fuel tap, drain the bowls, turn the fuel tap on again and check.

Check the fuel pump is pumping, remove the pipe from the carbs and crank it over - fuel should come spurting out.

Spray WD40 or eazi start around the carb rubbers when ticking over you may have an air leak - Im assuming you have removed the tank and air cleaner - revs will rise if you have and air leak.

Ill 2nd to to check the fuses are tight in the their holders - mate of mine spent weeks and £££ trying to find a starting and mis-fire fault, he knocked the fuse box by mistake and the thing cut out.

That should give you something to work on.



My money is on coils wired wrong! Or one not wired up at all.

[1308lee]

coils are all wired up right, red to red etc.....

exhaust does smell of fuel

does bang and fart like fuck

new plugs and coils.

fuses seem alright,

batterys ok

dying here without this bike :@

[dunkenb]

Sounds like you've got the leads to the spark plugs mixed up. Check they're as per the manual, just one on the wrong plug will bugger up the running.
Are all the exhaust headers heating up when on tick over ?
Have you cleaned the carbs, including the little brass air inlets under the plastic covers that hold the trumpets on.

[1308lee]

iv downloaded the haynes manual, any idea where id find the wiring info?

:'(

[petrolhead19]

wiring diagrams start from page 202

[gullarm]

Yup I reckon wired wrong - check the exhaust temps.

That should tell you which are wired wrong.

If one is wrong then two must be wrong. So firing on 2 cylinders only.

[1308lee]

stressed out like mad. we're gonna check the seals under the carbs tomorrow and check the exhausts for the wiring fault you talked about.

another thing confusing us, theres a wire that piggybacks the coils and leads to a small box under the clocks with MAS on it (i think) any ideas?