Rs 125 running problem

Jellybean696 · L Plate Warrior Joined: 04 Nov 2015 Karma :

Hi there cheers for any advice I have rs 125 just changed the engine over as old one had it.. it's not a brand new engine!store that thought. Once I had it all back together I got new battery now the problems start it cane to life and lights on and everything I start the bike with the ignition switch starts up rode it for like 3 miles and bike basically died felt like engine breaking and wheel was gonna lock so clutch in and pull over.. bike wont start battery is flashing and display is flashing on and off like the battery has died then no life at all filled water up as it was rather scarce and charged battery for few hours bike starts again test rode it and again bike after little 5 mins shuts down locks up and battery doing exactly same thing I stacted to push it home walking next to it I push the button and it starts reluctantly and when I bump it it starts as well I've got multimetre tester here so I kinda know where I am going with this can anyone help with advice as to wheather it's engine being starved hence looking of wheel trying to seize or is it gonna be battery or regulator issue any help would be great and sorry for long blogg but trying to be clear on first blogg

P. · Red Rocket Joined: 14 Feb 2008 Karma :

Erm... have you checked the actual engine. They need rebuilding fairly often and if its sat around for a bit its likely that it needs a full rebuild.

Jellybean696 · L Plate Warrior Joined: 04 Nov 2015 Karma :

It's been running but the answer is no I haven't checked it other than ride it and like I said after a little while it stopped but then bumping it would start it and ride bit more I've been told maybe I didn't bleed the oil when I put it back together? I not sure if I did but that would explain it trying to seize as such so I'm hoping get the oil following to it and battery charged it will sort it self out?

B0ndy · Spanner Monkey Joined: 25 May 2015 Karma :

Jellybean696 · L Plate Warrior Joined: 04 Nov 2015 Karma :

Thank you for ur time and advice it's passing it down here but went out there n tested battery while everything was off read 12 then put terminals back on couldn't actually get it started as display and power keeps flicking off as said earlier was gonna bump it but traffic is stupid at moment so I tested it with lights on and everything n went to 11.6 i know it's ment to be between 12.5 13 5 while off and 13 to 14 while on is that right sorry sound silly now lol and I didn't bleed anything after putting it back together so u feel that would explain engine breaking n stopping it's trying to seize what would a bad piston look like I no the barrel will be scrapped up if gone bad I've got top end barrel from old engine that seemed fine as well so could swap of it is a top end rebuilt

Jellybean696 · L Plate Warrior Joined: 04 Nov 2015 Karma :

Can i get some more help please lol I've done premix and charged the battery rite up it was doing the same thing doeing with fully charged battery display was flicking off I undone petrol cap and disconnected power valve system as there is no cable installed and it starlets up fine rode for a while gave it a bit of a run hovering over the clutch incase didn't cut out once I've got a oil leak clutch side as I fitted gasket without any sealant I know I'm a dick Ivery got exothermic one will fit it again and water that sits in radiator has ran out out not long ago topped it up what r people thoughts and do u recon that may be why battery and power wasn't happening coz of power valve

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

Rewrite those last two posts with punctuation, maybe split the problems and observations into bullet points, and you may get some help.

It's impossible to work out what the problem is from your confusing string of words.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Premix does need larger jets. Personally I wouldn't bother except as a short term bodge / trial. Make very sure the oil pipe to the carb is secure and hasn't become disturbed.

Battery voltage should be about 12.6v with the ignition off, around 13.5v with the engine just idling and going up to about 14.5v when being revved. Note with the RS125 the power valve is open up to 2500rpm, and the solonoid for that draws a lot of electrical power so take account of that when doing any readings at low rpm.

All the best

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

Jellybean696 · L Plate Warrior Joined: 04 Nov 2015 Karma :

It was around the 12.4 n about 12.8 with it running went up to like 13.7 whilst reving it I made a premix and took it out and it didn't lock up once so that's one thing that's proven rite from the advice so again how would u sort the oil pump out I've tried looking for manuals Haynes. After riding it today what should I be listening out for if had done some damage in engine as I was paranoid riding it trying to find a fault...... I disconnected the power valve after so I should test multimetre again with that out the picture for drawing the battery cheers again

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Voltage is a bit low. Are you measuring with a multimeter over the battery or relying on the battery read out on the clocks?

The oil pumps rarely go wrong (and they are driven from the same shaft as the water pump, hence if that fails the temp will go up very rapidly), although someone could have set it up wrong, or just left a load of air bubbles in the oil lines. I would bleed the line down from the tank to the pump, then run it on premix with the arm fully open on the pump until there are no air bubbles.

While you are at it, check for a cracked intake manifold (the rubber bit between the reed valves and the carb).

All the best

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

stirlinggaz · World Chat Champion Joined: 22 Jul 2007 Karma :

hi,
are those voltage readings taken from the bikes instruments?
if yes, ignore them & use a multi-meter.(the clocks are notoriously inaccurate)
the rs needs a good, freshly charged battery just to start.
any less than 12.5v & it might not start.
charge the battery up & start again with a NEW spark plug (a cheap BR9ES will do until you have it set up correctly) & fresh fuel.

DONT go pre-mix, the oil pumps on these bikes rarely fail. just set it up as described in the manual.

then put multi-meter probes on the battery terminals. (with meter set at 20v dc)
whats voltage when bikes off?
what does voltage drop to when you press the starter?
does the bike start?
after letting go of the starter button, what does voltage recover to?
then with bike running, (with lights on) rev it up, slowly right up to 6000+rpm.
what happens to voltage when you do this?
remember, the rs doesnt start re-charging the battery until your at 5500rpm.

cheers,
GAZ