RGV250 dropped a cylinder

**rgv250** · 22nd October 2010, 13:25

hey guys my rgv started back firing so iv cleaned exchaust out and redone flange seals and still doing it. a mate told me that the spark plug could be burning to hot and put a hole in top of piston? it will idle on one and the other one back fires every 10seconds or so. im really looking for a good 2 stroke or rgv mechanic around manawatu palmerston north. im guessing about 6-800 to rebuild top end and could be worth it but would like more info.... if someone can help? thanx

**White trash** · 22nd October 2010, 13:28

Originally Posted by rgv250

hey guys my rgv started back firing so iv cleaned exchaust out and redone flange seals and still doing it. a mate told me that the spark plug could be burning to hot and put a hole in top of piston? it will idle on one and the other one back fires every 10seconds or so. im really looking for a good 2 stroke or rgv mechanic around manawatu palmerston north. im guessing about 6-800 to rebuild top end and could be worth it but would like more info.... if someone can help? thanx

Sounds like a holed piston. They're also notorious for clipping a powervalve lip which causes some nasty bore wear. Dunno how keen Ozzy Performance is on 2 strokes but he's a good bugger. Also the Sales at Total Motorcycles may be able to help.

**imdying** · 22nd October 2010, 14:45

Yup, bad news, it sounds rooted.

Two things:
- Take the powervalves out and inspect them
- Take the heads off and inspect the cylinders and bores

If the cylinders are ok, then maybe $600-800, if not, assuming the crank is fine, then closer to a bit over $2000.

**White trash** · 22nd October 2010, 15:19

I've got 500 bucks to buy it if it turns out to be poked mate.

Let me know.

**rgv250** · 22nd October 2010, 15:22

iv jst pulled tank off etc and pull plug out put my finger over plug hole and kickd it over slowly and i can feel compresion, so does tht mean anything? i looked down inside cyclinder and cant c any holes as such...? dnt know much bout it but i wouldnt mind geting it going cheaply myself, could it be a carb prob? coil? any ideas would help but looks like i gota take it to a shop

**White trash** · 22nd October 2010, 15:24

Originally Posted by rgv250

iv jst pulled tank off etc and pull plug out put my finger over plug hole and kickd it over slowly and i can feel compresion, so does tht mean anything? i looked down inside cyclinder and cant c any holes as such...? dnt know much bout it but i wouldnt mind geting it going cheaply myself, could it be a carb prob? coil? any ideas would help but looks like i gota take it to a shop

Bring it to my place and go home with five hundy mate. I reckon it's clipped a power valve and munted the piston/cylinder lining.

Drain all the coolant out, pull that head off and turn the motor over so the piston's at the bottom. That will tell you enough to know if the bore has been damaged in anyway and you'll be able to see the crown of the piston to know if it is holed.

Edit: Have you actually tried jsut replacing the plugs first?

**rgv250** · 22nd October 2010, 15:29

i tryed swaping the plugs round and it stil did it on same one. i did get the bike cheap so i knew this was bound but i wanted it to happen after summer haha its worth bit more then 500 to me mate other wise id b keen. its got near new tyres and shit. well im thinkn bout goin to the shed to pull the head off. were are you from mate? thanx

by the way does it mean anything tht it happend at high rpm? at speed under load

**White trash** · 22nd October 2010, 15:46

Originally Posted by rgv250

i tryed swaping the plugs round and it stil did it on same one. i did get the bike cheap so i knew this was bound but i wanted it to happen after summer haha its worth bit more then 500 to me mate other wise id b keen. its got near new tyres and shit. well im thinkn bout goin to the shed to pull the head off. were are you from mate? thanx

by the way does it mean anything tht it happend at high rpm? at speed under load

Nah all good, I've owned a few and I know what they're like. Bear in mind when you start pulling it to bits, head gaskets are stupidly expensive for them and in no way reusable. On the OFF chance the barrel/liner and piston are OK and it's something else, I reccomend removing the motor and then taking the barrel off with the head attached. With piston/cylinder damage each time the motor turns over, the damage is being magnified. Especially if you've got little bits of piston ring swimming round in your crank cases. Good luck dude and let us know how you get on.

**rgv250** · 22nd October 2010, 16:01

yea mate i jst went and put it basicly back togeather and cleaned the plugs and kicked it over and it went mint first pop then after 30seconds started back firing again? all iv done is take carbs off and put back on tightly pretty much. they were all prety loose etc. the bike is abit dodgy. could it b the oil pump or is it worth pulls carbs off and apart? thanx heaps mate im stuck here cause i know alil but fuk all. and dnt really wanna have to pay heaps at a shop. thanx again

and wats the usall for how long a tank of 2 stroke oil last in ur ones? its does seem to use abit....

**Teflon** · 22nd October 2010, 16:55

http://www.rgv.ru/manual.html

http://cgi.ebay.com/FULL-COMPLETE-GA...item41522a914f

**White trash** · 22nd October 2010, 17:12

Originally Posted by rgv250

yea mate i jst went and put it basicly back togeather and cleaned the plugs and kicked it over and it went mint first pop then after 30seconds started back firing again? all iv done is take carbs off and put back on tightly pretty much. they were all prety loose etc. the bike is abit dodgy. could it b the oil pump or is it worth pulls carbs off and apart? thanx heaps mate im stuck here cause i know alil but fuk all. and dnt really wanna have to pay heaps at a shop. thanx again

and wats the usall for how long a tank of 2 stroke oil last in ur ones? its does seem to use abit....

Process of elimination I'm sorry mate. Could be blocked jets in the carbs. Could be a weak spark. Could be fucked HT lead. Could be a coil. Could even be a flat battery. No shit.

**rgv250** · 22nd October 2010, 17:18

the battery was new wen i got it and it seems mint with headlight on without goin. i think im gna look at couple new plugs and clean carbs and try again. other wise i gota try find coil etc and getin real hard to find any parts for it

mite just wack on trademe $1 reserve haha thanx mate im gna get it taken into a mates shed in twn and try get a mechenic to cme look at it as im out ashy so then i should know more and wen i do il post it cause hopfully good news

**onearmedbandit** · 22nd October 2010, 18:25

Two coils? Swap them over and see if it's doing it on the other cylinder.

**Peter Smith** · 22nd October 2010, 19:59

In my humble opinion you could waste heaps of time and money trying to find whats wrong. Take it to a good bike shop that has a mechanic who knows RGV's and ask him to find out whats wrong and get an estimate on what it would cost to fix it.
Those 250's are alot of fun, but need alot of maintenance.
Good Luck dude.