Hey there,

I've just bought a scorpa 250 2007 and it seems to not rev properly past mid revs. It's almost like its very choked and boggy around the top and as a result there's no power there!

It's had a new filter, cleaned carb out (without taking jets out admittedly), new plug and the air/fuel screw seems set right because the bike rides well at low throttle.

All the breathers are clear (not sure on the tank breather but doubtful that it 's the issue) and fuel is flowing well to the carb.

If anyone can shed some light on the situation please do!

Thanks in advance

Rob

double check the needle clip hight,,

very good idea! which notch should it be set to? thanks just thought though surely the needle height governs how much fuel is introduced into the mixture. It looks like it's getting enough fuel although I'm not sure!

Edited December 4, 201213 yr by betarob

take the jets out if some of the holes in the jets are blocked it wont run right do this before you adjust the needle if it ran right at the height it is now it is unlikely to need moving

Does this happen when you are riding it, or is it just when standing still revving it?

Are you pushing the choke fully down for "off" ?? It can be a bit fiddly with gloved fingers...

Nelly1 is right, was the bike runnig right before this hicup ?

if so leave the needle clip, and just give the carb a proper clean,, idealy with an air line

Right, cleaned the carb out throughly today, blasted out the main and pilot jets and ensured the choke is going all the way down. Went out for a little ride and it's certainly better! It's still flat at the very top end though which is horrible to ride with but definitely an improvement.

I also tried moving the needle clip up 1 notch and this just made it run lean everywhere. The clip is currently on the second from bottom notch. Is this standard?

I have been running the bike very rich in 2 stroke oil temporarily as I've only just bought it and wanted to make sure. Could this be the problem?

Edited December 5, 201213 yr by betarob

Mmmmmm, How rich exactly?

Be honest now.

And what oil?

well I worked it out yesterday its probably at around 45:1 haha! stupid I know I used scoot sport oil that silkolene do. I got it cheap but its been fine in all thje bikes I've ran before! I usually run at 70:1 but becuse the bike had been standing for a while I thought best to richen it up a little, I think I went too far!!!!

You make me hanker after the old day's when half a jar of engine oil to a gallon was my rule.

Bikes didn't run very well though ate plugs and smoked like chippers.

I've an 05 SY,it's happy on 70/80 ml oil per 5 litre using synthetic.

I wouldn't say these motors are too oil sensitive as i've known others to run much richer mixes.

Hope you've discovered the root of your problem.

PS if it isn't give it a try with the mudguard off,some aftermarket filters seem too thick and restrict airflow?

right just tried it with the mudguard off and airfilter out and it made a big difference, Revs a lot cleaner and nicer!

The filter I bought was unbranded, blue with a black rubber seal around the top, could this be the problem?

thanks

also found out im running a 145 main jet, does this not sound a tad large? thanks

Try it with the filter in place,but clean it and very lightly oil it first.

If it's ok then something must be restricting the airflow unless as you mention the main is too big?

Don't know sizes off hand, someone will already have them on the site.

There isn't any homemade rubber flaps over the airbox?

just looked into it and a 145 main is standard from the factory! ill try it out again tomorrow and report back.