250 Wet Dream

[gavcarter]

Id be tempted to bag all the brown stuff and post back to sender

[wots]

[SQL]

Guess you could say the carbs were a bit shitty https://img.photobucket.com/albums/v88/MyFemurHurts/null_zps621926ca.png

[dannymassive]

[STONEY!]

check the stator, had loads of these (like 20+) and the stators are all dying off, seems to be age not mileage that kills them, manifests itself in various different ways but always the stator causing the problems.

Running on one til warmed up
Poor running at low revs
Poor running at high revs
Surging throughout the rev range
large flat spots

All caused by stator failures, although I have had success in cleaning/replacing the connectors generally it still ends up that they need a stator plate replacement.

[wots]

Sounds about right, have replaced the carbs and they seem as perfect as possible. Came from a running bike. Today replaced the CDI with an OEM one. It had suspected CDI failure previously, an aftermarket CDI has been fitted (brand new). It seems like an electrical breakdown now, as it runs beautifully at high revs if it gets there and is more usable than it ever has been before.

I'd had the pickup suggested previously, so I think that's where I'm going next. As there is actually very little left. Coils are brand new. It now starts easily and will rev up to 4K albeit with a little stutter.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[wots]

Went to look for a stator on ebay, found one from a working bike. Should be here midweek. Will give that a go.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[wots]

It runs. Carbs need adjusting as they have been fiddled with many times. So sometimes bogs a little initially, but once above 2-3K it flies.

I think in all honesty it needed a cdi and a generator/pickup. I have replaced carbs (not needed, actually suspect the originals were fine) and the above two items.

Now just to sort the annoying sidelight problem, will wire to an ignition live for the MOT. I know it's not the switch as used another, I'll figure it out.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[Robby]

Don't go too crazy trying to sort the carbs. Get them clean, inc removing the mixture screw and squirting some cleaner down it. Make sure you have the same jet sizes and mixture screw settings on each one, then balance them on the bench - I tend to use a single strand of copper wire for this, to make sure the butterflies and opening and closing together.

Then do the valve clearances.

Then put it all back together and ride it for a bit.

Carbs can take a bit of use to settle down after being messed with. If you keep removing them and messing with them, you can just end up making more problems. If they won't settle down, you may have a problem, and it may be an unusual one. Throttle shaft seals can give up and be really difficult to diagnose, you get an air leak that varies its effect based on throttle position, temperature and engine load.

[wots]

Carbs are fine, just need resetting. No leaks, new rubber gaskets fitted on the manifold etc. Has been sprayed to death with easy start and it doesn't change the revs, whereas initially it was leaking from the mating gasket on the inlet and revving.

Just needs mixture right. I think 2 turns is the default and will work from there. I actually don't know where it's at right now, after getting it running, felt elated, had a BBQ so left it there.

After my experience with this so far, I am NOT touching the carb internals again. Clearances, noted. But this thing has only done 8K. Once past that initial bogging, it really flies, well for a heavy 250 anyway.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[wots]

MOT passed, on a proper ride managed to get 70 without too much pain, wouldn't want to run at that constantly. Still have a problem with the initial part of the throttle, sometimes needing to flick it in a particular way. Once above 3K it's fine and is never a problem, revs to the redline too.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[Bunny Lingus]

Like it, but I don't like the engine or the wheels. Chuck a single in it & some spokeys, lose the lard... Had the 400cc, the exhaust pipes alone weighed a ton & they rot out where the link pipe is... Motad cleaned up in the eighties offering 2into1 pipes at two thirds the weight & two thirds the price.
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Bunny Lingus & The Flipside Faggots

[wots]

[sabian92]

[Bunny Lingus]

[wots]

I've spent about £200 on MOT and getting it running, as it needed a new rear tyre, the last 4 years worth of MOT's had advisories for tyre cracks it couldn't pass another. Going to dare to take it to work tomorrow, 30 mile round trip through a mixture of all roads and traffic volumes. Should be fun, wish me luck.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[-Monty-]

How did the ride to work go Wots?
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Present: [Kawasaki ZX7r][Suzuki DRZ 400s]
Past: [Honda PCX 125] [Yamaha RXS 100] [Honda CB 500] [Triumph Speed Four] [Honda ST1100 Pan European - Po-Po Edition]

[pepperami]

This thread has to stop right now! : it`s making me feel guilty about not getting the bits for mine to put it back on the road
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I am the sum total of my own existence, what went before makes me who I am now!

[wots]

[Bunny Lingus]

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Bunny Lingus & The Flipside Faggots

[wots]

I broke it, trying to fix the brakes.
Opened the Reservoir and the rusty screw snapped right at the bottom somewhere. Fluid was awful.
https://i1312.photobucket.com/albums/t525/wotsthestory/CB250N/20140725_154402_zpsbdxp5qep.jpg~original
Also bought this, I thought whilst doing it, I might as well try and make it as good as possible. I don't want to change much from standard but as this was £20 it seemed like an investment.
https://i1312.photobucket.com/albums/t525/wotsthestory/CB250N/20140725_154424_zpstqvbbtyg.jpg~original

I can get a replacement reservoir for £30, I'm probably better off buying a secondhand master cylinder and reservoir together though? Which Master Cylinders would be direct fit from other models?

EDIT: CB500 looks very similar and has the mirror mount. They are cheap too. Any good?
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[Bunny Lingus]

400n but look at the more modern CB250 ones too 'cos they were single disc.
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Bunny Lingus & The Flipside Faggots

[wots]

[wots]

Cleaned all the jets out, I got myself one of those carb cleaner things, that looks a bit like a set of feeler gauges. Did the job brilliantly. Now idles just fine, but you do need to still give it a bit of throttle to set off, but it always revs up, whereas before it need a number of flicks of the throttle to get the revs up.

Unfortunately, the floats are giving me grief now (I didn't touch them), if I leave the tap on it just pees through. So they'll have to come off again.

Monkey bike front brake and new braided line much better than last week, although new Master Cylinder on the way.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125