RM250A HELP NEEDED

[PRITCH39]

Hi all,

I have just done a freshen up on my RM250A. The bike was running very strong but was a bit down on compression so I fitted new set of rings and Boyesen reeds new gaskets etc. I went to ride it but the bike now continually floods and fowels plugs. Could there be a problem with the reeds? when I managed to get it to keep running it is extremely under powered and slow and seems to get hot.

Any ideas guys this is shitting me

Brian

[Davey Crocket]

Have you got a gutfull of fuel?...needle leaking?...try and free rev it stationary untill it gets crisp.

[oldfart]

Brian ....Give the carb a complete strip down using compressed air blowing thru all bleed holes.

Check float level hieght etc      were the reeds sitting flat when tighted up ( with no gaps ) if not rotate thru 180 degrees

Hope this may help.

 

[suzuki27]

Sounds like the reeds. They are prone to crack etc.Check their gap/condition etc.

[Marc.com]

You didn't take the piston off the rod by any chance.

[DR]

  and put it back on facing the wrong way..arrow on crown points to exhaust, if no arrow the ring locating pins should be toward the inlet side (facing rear).

[PRITCH39]

New piston, fairly sure it is on the right way but will double check and change back to standard reeds while im at it.

Thanks
Brian

[TM BILL]

Enlighten me as to how putting the piston in backwards would cause the described symptoms  on this model all i could see happening is thr rings picking up in a port 

[PRITCH39]

How well are reeds supposed to seal? I just pulled the barrel off and the piston is right. filled reed void with water and it just pisses out. Turned the reeds over to try and achieve a better seal with no improvement, so I put the standard reeds back in filled with water and SURPRISE no leaks. Could this be my problem? I pulled the carb apart and found no problems there. Am I doing something wrong with the new Boyesen reeds? I will put the bike back together when the base gasket arrives and let you know how it goes.

Brian

[DR]

There is an acceptable tolerance (gap) of 0.20mm for the reed petals in regards to an air gap clearance from the base/seat to the petal. The water test may not be an accurate indicator. I'd try the stock petals, process of elimination with what was changed

Bill, with the piston around the wrong way I was thinking of rings (ring) jammed in the groove on the exhaust side not sealing making the engine struggle and non responsive. Just a stab..

[Marc.com]

Am I doing something wrong with the new Boyesen reeds? I will put the bike back together when the base gasket arrives and let you know how it goes.
Brian

Did you assemble with the stock reed stops or upside down.

[PRITCH39]

I used stock reed stops. I fitted reeds in the following order.

1*large reed
2*small reed
3*reed stop

Brian

[PRITCH39]

Hi all,

I finally got it sorted, the problem was the stator. The bloke who rewound it for me said he hears the same story all the time, bike is running well, owner freshens up top end/full rebuild and bike wont go anymore. Apparantley the new compression puts out the flame/spark resulting in anything from very poor performance and flooding symptoms to no spark at all. $160.00 got my stator rewound, all new wiring and plugs and a new coil. The bike starts first kick and goes better than it ever has as long as i have ownd it.