13 replies to this topic

[alanhutchinson]

Hello. I have an 03 rev 3 250 and there are a couple of things puzzling me.

The 1st thing is the bike will not start with the choke. It starts and runs beautifully without however as soon as I stick the choke on it borks out and dies. I have had the carb in bits (after one of the floats stuck) and cleaned it all out with carb cleaner but this has made no difference. SORTED! THANKS!

Next question is my gears can be very hard to select sometimes when stationary. This doesn't always happen but occasionally it will not change gear at all. I have changed the gearbox oil twice in 2 rides to see if that was the problem. But still the same. ALSO SORTED!

Thirdly. My rear brake bites a bit far down the pedal and is a tad spongy. There's definitely a small amount of air in the system and needs bleeding. I tried to bleed it through the conventional way with a piece of pipe on the nipple but this made matters worse. I then bled from the bottom up and it got a bit better but still not brilliant. Is there a technique that's well suited for these? ALSO SORTED!

Any help much appreciated.


Edit: After sorting the above issues out i decided to take a look at the engine kill switch which has never worked. Turns out there's only one wire connected to it... Has anyone got a wiring diagram for the 03 250 i could take a look at? Or perhaps just a photo of the wires it goes into? The one that it's plugged into at the moment is black and white. I understand i am looking for a fully black wire coming from the regulator (according to a wiring diagram of a different model is this correct?) But i cannot find such a wire.

Edited by Alanhutchinson, 16 April 2012 - 02:06 PM.

[alanhutchinson]

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[alanhutchinson]

Also would like to add. Regarding the rake. They are recent pads.

[copemech]

New pads can be soft from the outgo and require thermal cycling to firm up. Best to do a couple three hard stops from speed trhen let cool to resume normal activity, then re-do as neccessary. After a few cycles, do the same and douse the hot rotor with water to steam it off. Possibly again, yet do not overheat them trying to quicken this process as you will ruin the pads and must start over.

[alanhutchinson]

Hello and thanks for your fast reply. The pads are not brand. Ew but are recent and are definitely bedded in. I know this because being a numpty let a bit of fluid out of the brake to try and slacken it of a little bit which back fired majorly

Thanks!
Alan.

[gazzaecowarrior]

Could be worth trying ATF fluid in the gearbox. This helps smooth out the gear selection.

The rear brake is a bugger to bleed on the rev 3. I use to backbleed it too. Seemed to work better than a top down approach.

[pindie]

1. Carb settings may be very rich already and putting the choke on floods it. Follow the Beta carb set up guide on this forum or Google Beta Carb setup rev 3 to get the foat height sorted. I am on the third clip notch from the pointy end of the needle.

2. Bleed your clutch. Suck old fluid out of the master cylinder pot and fill with new. Then place spanner and 1.5m of clear tube over nipple. Attach the open end of pipe near the handlebars. Next just open and close the nipple. Now pump the clutch lever with your hand to build pressure, on the last pump hold the lever in and only slightly and gently open the nipple and 1/8th of a turn, maybe a little more if no movement. As the cyliner is so small it is easy to lose pressure and your buggered. Repeat this process until you see new fluid in the clear bleeding tube. Finsh off job and tidy up.

2b. If bleeding does not cure it try using Putoline Nano trans oil in the gear box. I'm running it and it is smooth as you like and seems to last a lot longer than ATF or light gear oil before it gets notchy again.

3. I use the same method for brake bleeding as the clutch. Mount pipe from nipple to handle bars and only very slightly ever crack the nipple. If you open it too fast the drop in pressure is hard to get back. Be gentle and patient and it'll bleed ok. The long clear tube is a god send here as you can always for a syringe into the open end of the tube to back bleed or suck etc. I have sucked on the tube myself with my mouth - you can do this as you can see the fluid moving in the pipe and avoid a mouthful.

Edited by pindie, 12 April 2012 - 05:36 PM.

[totalshell]

PLEASE PLEASE do not suck on the pipe I lost a friend who inhaled petrol syphononing like this it was not pleasant..

[pindie]

Sorry to hear about your friend.

I never said suck petrol? And the reason you use a long clear pipe (1.5m) long is so that you can stop in plenty of time. As always always use extreme caution.

[alanhutchinson]

Thanks for the input. Really appreciate it. I will bleed the clutch after the weekend and see if it makes a difference. With regards to using ATF fluid. That is exactly what I have in it now and seems to work a lot better than whatever was in it before. I shall also have a search for the carb set up guide and report back once I've given it a try.

Thanks
Alan

[alanhutchinson]

Okay. I got a spare half an hour this afternoon to get the bike out and set the carb up. I have cleaned it out, set the mixture and idle speed and set the float height. The choke still is not working as it should be... It's definitely an improvement as before it would not run at all with the choke engaged but it does now, although it borks and will not idle, let alone function as a choke should. See video I've posted below.

[grumpyoldman]

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[grumpyoldman]

Although I have little experience yet, my Rev 3 only needs the choke to start from cold and I need to turn it off straight away and it idles fine from then on - if I leave it on it runs as rough as old boots.

[alanhutchinson]

Thanks very much. All issues sorted. Bled the clutch today and it's working perfectly ! Added a new question to the original post aswell. Killswitch problem!

[grumpyoldman]

I downloaded a Beta owners manual from their own website but the quality is rather poor so the wiring diagram and service schedules are difficult/impossible to read.
It certainly looks like one wire and an earth but I can't read the colour.

Is there a decent workshop manual for these bikes?

[alanhutchinson]

I have the manual you speak of and yeah the diagram is nigh on impossible to read. It's definitely not an earth wire... It's a + and - wire of some sort as the button breaks the circuit. That's all I know!