Hi folks please can anyone help before i lose any more hair.

Bike was running 2 weeks ago sweet as a sweet thing, went out to take it for a wee ride on sat and would not start.

All i get is it attempting to start then a sonic boom and a bang from the can, must admit to almost messing my pants the first time as in front of the garage open door was the mrs wee Rx8 and i had visions of a lump of coal firing through the windscreen lol.
Sorry i went of on a tangent there.

So ive checked the following, fuel on , fuel getting to carbs, fuel not sparky in chamber causing sonic boom as it exits.
Checked all fuses there sound. plugs are bone dry and only just fitted about 100 mile ago along with recon coils from Mr GF.

No spark at plugs, now i have disconnected coils and hooked them up to wee volt meter and there is power going in. No idea how to check power coming out. Could this be the problem or should i be looking elswhere for the problem.

All advice welcome, cheers in advance

erm I'm confused....

are you getting a big backfire when trying to start the bike?

If so then there must be a spark to ignite the fuel???

if this is the case I would be chcking the HT leads.

Check the HT leads are firmly attached at the plug cap and coil if they have been reconditioned recently. They are bastard tight to do up on new leads.

Did you check for spark with a spare plug grounded against the frame? Was it all or none that gave no spark?

Most common cause is wrong lead on wrong plug, but if you rode it last week and hadn't molested it since that can't be it. I would go with intermittent and weak spark from a dodgy connection.

Check the continuity of the wires from the CDI and Power (Black, yel/blu and blu/yel) to the coils as well.

Good luck.

tanuki wrote:erm I'm confused....

are you getting a big backfire when trying to start the bike?......... yes loud bang and smoke

If so then there must be a spark to ignite the fuel???........... my thoughts exactly

if this is the case I would be chcking the HT leads.

Not as confused as i am m8 lol

Cheers for getting back to me

greggo wrote:Check the HT leads are firmly attached at the plug cap and coil if they have been reconditioned recently. They are bastard tight to do up on new leads.

Did you check for spark with a spare plug grounded against the frame? Was it all or none that gave no spark?

Most common cause is wrong lead on wrong plug, but if you rode it last week and hadn't molested it since that can't be it. I would go with intermittent and weak spark from a dodgy connection.

Check the continuity of the wires from the CDI and Power (Black, yel/blu and blu/yel) to the coils as well.

Good luck.

only took 1 plug out and ground it against frame and no spark present. although ive been working on the forks, plastics, shock ave not touched any of the leads and it has run fine since i fitted new plugs, leads, coils.

Will check the continuity of wires and see how that goes will also get all plugs out and check for tightness of all leads caps etc.

Cheers for getting back to me m8

assuming everything else is right, another one to try might be drain fuel from the float bowls of the carbs

seems to work on my nc23 if its been sitting for a bit and i didnt drain it before it was left sitting

also fresh fuel in the tank, idealy drain the old stuff, but ive gotten away with just mixing new stuff in and then firing the bike up

does take a wee while mind, until the fuel is through the pump and filled float bowls enough to cause it to run

best of luck anyways

dunky wrote:

greggo wrote:Check the HT leads are firmly attached at the plug cap and coil if they have been reconditioned recently. They are bastard tight to do up on new leads.

Did you check for spark with a spare plug grounded against the frame? Was it all or none that gave no spark?

Most common cause is wrong lead on wrong plug, but if you rode it last week and hadn't molested it since that can't be it. I would go with intermittent and weak spark from a dodgy connection.

Check the continuity of the wires from the CDI and Power (Black, yel/blu and blu/yel) to the coils as well.

Good luck.

only took 1 plug out and ground it against frame and no spark present. although ive been working on the forks, plastics, shock ave not touched any of the leads and it has run fine since i fitted new plugs, leads, coils.

Will check the continuity of wires and see how that goes will also get all plugs out and check for tightness of all leads caps etc.

Cheers for getting back to me m8

Could try checking your kill switch aswell mate.

My NC23 did the same to me a few days ago, I tried everything, last night I charged the battery and changed the air filter. I didn't try until tonight when I flicked the kill switch a few times it fired up almost straight away, so I'd say it's worth trying the kill switch as said above (Y)

Click. I just realised ive seen this before.

The nc23 likes a good prime battery or you will get this exact issue. Even though the battery appears good because the engine is cranking it wont fire. I bet the house a fresh charged battery will get you up. I doubt recharging your existing battery will work, it didnt for a mate here who had this issue.

just had the same probs on my 23, put battery on optimate overnight, she fired straight up!!think batt being dodgy, when you try and fire it up, it floods,and then won,t fire till it,s dried out, i put a fan heater against mine first..ted