NSR125 having a strop

[Tristan.]

Ugh, unpleasent night. Went to pick something up at about threeish. Warmed the bike up for few minutes till it was happily idling, then rode sedately, cos of the ice. Though I did notice the engine note sounded a bit off above 7k rpm, and it seemed a bit gutless, didn;t pay any attention to that at the time.

Anyway, heading back, ten minutes into the journey the bike sputters a bit, and starts loosing power, in a running out of petrol sort of manner. Switch the tap to reserve and it dies, turns out I was on reserve (second time I've done that actually ) head into a sidestreet, and flip the tap back to reserve, she wont start on the button but after being bumped she does a good few hundred feet before dying.

Cue me pushing the bike 4 miles up the road, and having some utter fucking tool hit my helmet with his wing mirror, as I was stood stationary, with brake lights on, on the furthest left part of a wide straight road I could be

Anyway get to the petrol station, the tank isn't bone dry, but I only had a fiver, so I couldn't fill it to the brim to work out how much was in there, which'd probably of been usefull.

Press the button and she's turning over fine, but not catching, cue more bump starting action, all this does is provoke much curtain twitching, sweating and a depressing wet fart sound which dies after a few seconds. Theres a chance I flooded it, but I turned the tap off and gave it a few trys, and then on again, and every attempt yielded the same results.

Then I started to get paranoid about top end bits dropping into the crankcase, so I decided to leave it, my toolkit was in my backpack, but my friend borrowed it the other day and I'm missing loads of bits, most importantly my ten mill spanner, so I couldn't get the plastics off, or the tank, which meant I couldn't reach the sparkplug to check for sparks, or guess at compression.

Anyway a depressing busride home followed, and the bike is sat next to a lampost wearing only a disklock

Hopefully it'll be something stupid like a blocked fuel line, or even just a flooded cylinder, which coupled with the freezingness was a bigger issue than it should of been. However it is well overdue a full top end rebuild, which I was hoping I could put off till my january loan came through (student) do my symptoms match a siezed engine? I was presuming it'd be more impressive than this, considering it was turning over after being bumped, but the dying could be because of a lack of compression I supose.

So yeah, question time, when a two stroke siezes, does it do it like that.

Oh and just for the sake of completeness, a couple of random bits about the bike; the clutch wasn't fully engaging beforehand, so it would only roll in neutral and the indicators all stopped working a week ago and it was too cold for me to go find out why, plus I left my multimeter in plymouth.

[baldy]

its probably some muck got into the carb when it used up the petrol, or possibly running out of petrol and making it run lean has finished it off. I suspect it will run fine when the plug is changed.

Did the temp gauge go really up?
____________________
One day i will rule the world, just not today.

[alains]

generaly when the engine seize your back wheel will block and you will probably drop out or if you are lucky you will feel to be on the brakes . your symptoms look like a fuel line blocade or a loose contact on ignition .
1rst take out plug , put bike in gear and push it . if it moves smoothly it's a good sign but you cannot take seizure off , then take the compression , must be around 140 psi +-20
if it's low you need a top end rebuild
____________________
the worst day fishing is better than the best day working

[ncrn]

If it had siezed then when bump starting the rear wheel should have locked up instantly so sounds more like a fuel problem as you said it was occasionally catching.
____________________
Past: 55 Sym Jet, 91 ZZR250, 03 NSR125R. Present: 97 ER-5.
https://www.nsr125.co.uk - NSR Owners forum.

[ms51ves3]

I would say that it's a dirty carb.
Never could get one of my mopeds started but after a carb clean and a new plug it fired stragiht away.
Try changing your plug too.