She has new rings/plug/fuel filter/oil/carb clean..you name it. Went for a start after quite a long restore period and not getting any joy. Getting spark but can`t be sure about compression as I don`t have a test kit. Also wondering about the carb..maybe must come off again for another clean. Tomorrow will try some fuel in the cylinder to see if she wakes up.

New rings Mac" you"ve had the head off then , hows the timing,,

Just rebuilt my Suzuki and that would not start either, 4 new plugs at £48 all dead when under pressure, sparked a treat out of the head but nothing when fitted.

Gave the engine to mechanic friend to do the rings, hone and timing..so have to presume its ok.

Some fuel in the cylinder and quickstart in the intake got her going. I broke the gasket between the carb and cylinder when I installed it which I`m sure must definitely be causing hard starting (tested with some quickstart in that area which caused revs to rise)..so will replace it.

Otherwise its maintaining a reasonable idle but revving is erratic (revs stay high and come down very slowly..most likely the gasket).

Ok time to check out this carb..got it off today (real pig getting this carb off - everything in the way).

Stripped

The accelerator pump diaphragm..cant see any tears or holes

But I notice something here..look how far the tang on the floats bent down (never seen one bent so far down). Logic says this will cause bowl to underfill which will lead to the hard starting.

Is there a way to check float height like on the DT`s with carb off? as the manual has some weird procedure with a tube on overflow..carb must be on the bike and it must be running.

On the XT500 the measurement is 22+-2.5mm. Don`t know the 250 though. Measured it at around 20 with this method.

Ok I`m stumped..did a test like in the manual but with carb off the bike. The float level looks ok.

Looks to me that the tang will shut the fuel off far too early. I have not seen one bent this severally before.

The float bowl will have harldly any fuel in it.

Sorry, just re-read post, you have already sussed this.

That`s what I was thinking. Manual indicates fuel level must be 3-5mm under top of bowl edge, funny thing is it looked ok. I`ll test it again with carb on the bike and bike running to see if its still right. Another concern might be the choke circuit..best way I`ve heard of testing it is activate choke with bike running and see if it dies.

Anyone have any other comments on this float level tang story? Considering Boxer`s comments I feel like just bending it back a bit to see if it helps as this carb is a pig to get off again.

I haven`t mentioned here the bike once started idles ok but has huge flat spots in lower rev range. Got to pin the throttle to get it going.

Well bent the tang and its definitely starting easier. But still huge flat spot 3-4500rpm. Cleaned carb again..but that damn accelerator pump got me wondering...wish I could just bypass the damn thing. What about valve adjustment?

Flat spot deffo the carb,,, can you swap it , its the best way to illiminate the carb,,

Nope..thats not an option.

fettled all day to get sum sorta setup for this accelerator pump to work properly. Played a bit with float setting..still starting easier...(4 kicks instead of 40).

I`m noticing this..it seems to pull fine when cold..but soon as it warms up the flat spot comes back??