RGV250 problem

[TygerTung]

I have this RGV250 I am doing a few repairs on for a friend, had a stuck clutch and a broken footrest hanger.

Fixed those no worries, but it has been sitting around for about a year and isn't running very well.

It goes fine in first, hits powerband, bit of a flatspot, but maybe that is normal?

In other gears apart from first though, the powervalves don't seem to open?

Gun it in first, hit redline, change into second, and it's real flat, hardly accelerates at all!!!

Or if you are in second for example at lower revs, and open her up, it will start to pick up a bit when the port timing is optimum for the lower revs, then just go real flat as the powervalves don't seem to open.

What could cause this?

It's probably about an '88 model and has 44k on the clock.

Any advice would be appreciated,

Cheers,

Sam

[imdying]

When you hookup the wire for setting the valves, they both move correctly?

[TygerTung]

Which wire is that sorry? I havn't much RGV experience I'm afraid.

[imdying]

http://www.rgv250.co.uk/powervalve.htm

Have a look there... looks like the VJ21 doesn't have a wire, so saves hooking that up :)

But if you suspect a powervalve problem, strip and clean them, then set them up as per the instructions. Insepct them carefully for signs of damage or cracking.

[F5 Dave]

. . . and top one esp dropping onto piston. Almost invest money on it.

But the good news is that you don't own it - so sew it back together, deny all knowledge & invest your time into something more useful, like fettling shiny piped Yamahas.

[ttnz]

DITO, but if you up for a chalange check the web site mentioned first download the manual and remove the power values and see what comes out, most of the time when they drop they catch the piston chipping the side and breaking the rings, you can inspect this with a torch looking in the cylinder with the power valve removed. good luck