ns125r-k wont start help!!!!!!!!!! please!!!!!

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Hi all i have an ns125r-k 1990 that i am rebuilding. I have tried to start the bike this morning after getting some fuel. I have checked that there is a spark coming from the plug and is fine has a spark. Fuel is flowing to the carb fine, as i have fit a new fuel pipe and fuel filter. could it be fuel not reaching the cylinder or could it be the kill switch as i have fit the whole wiring loom my self an could not have wired it up correctly, as i am not great with wireing. Also could the ignition timing make a difference at all. I belive the bike has been stood a while. Would removing the carb an cleaning it help at all. any help would really appreiate it Cheers.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

If you are getting a spark then that suggests that the kill switch wiring, etc, is fine.

Possible fuel isn't getting through. Also possible too much fuel is getting through.

I would suggest possibly trying to get someone to give you a push and bump start it. Fair chance that would start it and also fair chance that once it has started and had a chance to clear out the rubbish in the engine it will start more easily in the future.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Hi Cheers for the post, i would bump it off but the front wheel is not fitted as i snapped the plate, that fits to the bearing that holds the speedo drive in place. Also it wont go in too gears easy it gets solid stuk some times, it will go it 1st gear but not always. That is what i would of done bump stated it but unable too. Al try clea the carb out and if there is too much fuel coing through how can i stop this from hapening. Cheers

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

For the gear change, check that there is sufficient oil in the gearbox and that the clutch is adjusted properly.

Point about too much fuel would likely be the needle valve not sealing. Either from the float heights being wrong, some dirt in the needle valve or the needle valve itself is worn damaged (it has a small rubber tip which can easily wear out).

All th best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

i have drained the transmission fluid and replaced it. Its really strange the clutch as i have adjusted it as far as i can. When you put it it gear and push the clutch in fully the bike is still in gear you turn he rear wheel a isin gear still. sound like its not dis engaging the clutch at all very strange. but i ill make sure i have toped up enough tranmission fluid and will check the carb as i did not altor the float height i will have a look an let you know thanks so much for the help means a lot. Gareth

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Clutch plates are probably sticking together. Suspect they would free off rapidly once you got the engine started.

The float height can change with time. It is just dependent on a thing metal tang which can bend slightly with time, plus the floats themselves can develop holes. However probably neither are that likely as a cause of it failing to start totally.

You could also try the bodge solution of a can of cold start. Take the airbox lid off and filter out and squirt a bit in while kicking the engine over.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

easy start never thought of hat good idea. Very bodge job but should start it f to get some now cheers just spray in stright where the air box was cheers

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Got it to start mate. I tried using the choke an it started. Just need tweaking a liltle. Thaks for all the help could not done it with out you, no need fo the bodge now lol take care. Hope you dont mind me asking do you have a bike at all. You seem to know what your talking about.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Have a few, including an NS125F in pieces and a crashed NS125R bought for spares.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

bradh511 · Scooby Slapper Joined: 30 Apr 2009 Karma :

I would check the gear problem as i have the same bike as yours and the main gear shaft bearing has gone 2 times. and you need to replace crankcases.

I am also sorry to nick your post how simular is the Mtx 125 engine ive been told it uses the same parts. But will it fit in my bike

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

The normal MTX is a fair bit different. Think the engine mounts are in the right place but you need different spacers (this is going on something I was told 20 years ago with someone fitting an NS engine into an MBX). However it probably depends on which MTX, as I think some models (not sold in the UK) were built at the same Italian factory as the NS and it wouldn't surprise me if they used the same engine.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Wont start now will only start with easy start, fires up only for a second. I pull the throttle back revs an then dies out anyone any ideas. An dont worry, no problem in using my post i dont mind. cheers Gareth

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Check it is getting fuel through. Using Easy Start you are running off that stuff as fuel, and as soon as that is gone the engine will stop. Often once it has started on it then it will keep running.

Also worth draining the fuel in the carb and possibly the tank if it has sat for a while just in case there is a bit of water in there.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Hi Keith,
The petrol used is not old only bought today, an has noth had fuel in it al remove carb drain fuel an give a clean a check for blockages. An like you said, i dont think fuel is getting to the cylinder.

Cheers Gareth

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Take it when you took the bolt from the bottom of the carb the fuel came out? As an aside, that drain bolt holds the main jet.

Probably worth taking the carb off and checking the idle jet circuit is clear. Will be a very tiny hole for the fuel and can be blocked easily (such as by dried up fuel).

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Hi Keith,
Took carb off cleaned checked evey where for blockages could not see any. But it back even worse wont even start with easy start now. Had it running with easy start after putting carb back an reved higher. Went to kick it off again but no luck, wont start at all. I still think no fuel is reaching the cylinder, but have no idea why. Think al leave it for now try in morning see if it will start then. thanks for every thing Keith you have been a great help.

Regards Gareth

bradh511 · Scooby Slapper Joined: 30 Apr 2009 Karma :

hmm what are the reeds like ? if carbs ok then only somthing in the reeds can be stopping it ?

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Sorry dont understand what do you mean by reeds?

Regards Gareth

tonyts50 · Trackday Trickster Joined: 12 Jul 2009 Karma :

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

I know what ya mean now, what is the purpose of the reed valve. An how will i know if it is faulty. I thought that was some type of filter. I have noticed that fuel is leaking from bottom of the carb out of a breathe pipe just dripping out dont think that is normal. An could the engine be low on compression an be the reason it ant starting.

regards Gareth

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Low compression could make it harder to start and reduce performance. Easy to check though with a compression tester.

The reeds are there to stop the fuel / air mix taken into the crankcases being pushed back through the back when the piston starts to move down.

The fuel dripping from the "breather" sound like it is overflowing. Ie, float height wrong or needle valve not sealing.

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

well i dont see ho it could be low on compresion. i have refitted a new head gasket. I will remove the reed valve and adjust the carb see what happens then.

Regards Gareth

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Remove it and check it. The bike does need one!

Compression being down is normally a sign of worn rings. The NS uses a plated barrel which is VERY hard wearing (just costs a fortune to repair when it gets damaged).

All the best

Keith
____________________
Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

Gareth · Nova Slayer Joined: 03 Nov 2009 Karma :

Hi

I came to my bike this morning, before i removed the carb and reed valve. I checked that there was a spark at the plug (which is a brand new plug fitted) but there was no spark. This will explain why it would not fire up with the easy start. I hope my ignition coil is not damaged or any thing to do with the cdi unit. Just seems very strange that it was firing one min, before i took the carb off then it didn't. Also the wiring loom is not all wired up an it keeps blowing fuses due to a short circuit would that have any thing to do with it.

Regards Gareth