Hi all im new to trials bikes and am in need of some help getting my sherco running.

I recently sold my road bike to have some fun on a 2000 sherco 2.5 which I bought as non runner, after some fresh fuel and a carb clean she kicked into life but wont idle and runs like a bucket of old rusty bolts, there is no piston slap or unnatural noise but sounds like a two cylinder running on one. as the carb is different from what iv experienced with older 2 strokes I didn't notice at first that the needle drops into a threaded hole which I now believe should be home to something called an atomiser of what size im unsure and don't seem to be able to find any info on net so some help would be much appreciated. also I cant seem to be able to get the clutch to unstick, would an oil change help or do I need to remove and rub up plates? its taking its toll on me as I would really like to have a ride.

my carb is a dellorto PHBL 26 BS. will be grateful for any advice.

http://www.motoguzziclub.co.uk/tech/dellorto_tuning_guide.pdf

See also Delloreto Uk website for details of specific carburettors and parts.

Once you get the engine running roll the bike forwards and slip it into gear, pull the clutch in and open and close the throttle repeatedly, clutch should free off.

On the dellorto carb there should be a half round brass piece that enters the bore of the carb by about 3mm as I recall(I no longer have one in front of me). Need drops into it. There may be threads visible from top, as the part needle goes into sits below.

Insure you have properly cleaned the pilot jet with a fine wire passing through it. Anything less will not suffice!

Clutch plates may stick HARD after long periods of sitting(or short). Fresh oil helps, but you may have to separate them manually if you cannot put the bike into high gear and rock it with your butt on seat with lever pulled in. The surface tension thing it is, a trials bike thing!!!! Be carefull with this allways, as they will catch you out after sitting, and you suddenly run into neighbors car!

Hope that helps!

thanks for the help guys, I read masses of pages and now fully understand how, when and by what means my carb works so got on to splat shop and they advised what size atomiser I need and a new needle and seal kit are on there way to me. clutch plates stuck hard can only get up to third with engine off ! have now done plenty of miles forward and backward so wife will be pleased when she comes home tomorrow and my bike is in pieces on kitchen floor .

hopefully should have a good report by weekend. cheers again guys

My buddy has a newer Sherco and the dealer gave him strap with Velcro to wrap around the clutch lever and bars (as if holding the clutch in with your finger) when he leaves the bike off for more than a day. If he uses it, no sticking. If he doesn't wrap the lever to the bars the clutch plates stick when he starts the bike.

ok stripped and cleaned clutch, fresh oil and new bits on carb and its still running the same. idle adjust does nothing. its sounds like to much fuel so im starting to think choke is ify, it starts from cold with no choke, if run with fuel off just whats left in the f/bowl, as its running out everything runs and sound perfect for a few seconds and throttle is very responsive. im after a quick fix instead of replacing everything straight away so that the wife doesn't think im spending too much money on it

You did put in a new spark plug, right?

When you had the carb off, did you check the height of the floats? Set wrong can cause excess fuel.

Remember that the mixture adjustment on DelOrto's is a fuel screw, not an air screw.

Make sure the engine can breathe - clean air filter and exhaust baffles.

Although I do not hav it in front of me, there are a few points on the Dellorto.

Obviously, the choke ON position is with lever UP, off is horizontal. There are seals on that simple piston circuit as I racall, as well as an o-ring where the tube sticks into bowl.

Your slide needle clip needs to sit in the slide below the lower plate in the slide assy. with spring on top the plate!

Be sure floats are not heavy and full of fuel sloshing inside.

Send the carb to Splatshop Chris for a ck if unsure about it, don't cost much.

clean banjo filter too