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Problem since rejet.

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Hey all,

Since I rejetted my SM a couple of weeks ago I've been having a problem which is more annoying than anything (and it may not be a problem - maybe they're meant to be like this?)

I rejetted, and since then every time I snap the throttle on (rev it quick and hard) from idle the bike stalls.

My bikes deets are:

2010SM

Sea level

Minkuni Carb w JD Jet kit.

Blue Needle

3rd Clip

160 Jet

Stock pilot (22.5 i think?)

Extended fuel screw 2.75 turns out.

3x3 mod

K&N Filter

Yoshi RS4Duals

I dunno what's going on and I can't afford to pay a shop to fix for me so I'd appreciate the help. And apologies for my noobness.

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When I open the throttle. If I open it quickly it stalls straight away.

Almost as if the bike senses I'm about to open the throttle and gets a little fright and stalls.

If I open it slowly it doesn't stall though.

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think he means when he opens it

but what did u change from before??

id be looking at the pilot circuit

fuel screw etc...

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Something else that might help is a larger pilot jet. We're running 27.5 around here with good results. About 800 ft alt. Also you might look for a small ring of crud that forms around the needle right where it goes into the needle jet. That can cause an off idle problem.

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Thanks everyone!

I'll try the 4th clip - and if that doesn't work I'll maybe move to the larger pilot jet - although I thought that with the extended fuel screw you were meant to keep the stock one. Time will tell as I do some fiddling.

PTgarcia - what do you mean does the fuel screw respond correctly? What sort of behaviour should I be seeing when I screw it in or out? At the moment there isn't a noticeable change when turning it in or out.

Also - if all I'm changing is the clip on the needle - I shouldn't have to take the whole carby out should I? Just release the clamps and give it a twist?

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pilot circuit procedure-

http://www.thumpertalk.com/forum/showthread.php?t=327405

needle changes can be done with the carb in the bike.

resist the urge to put a bigger pilot jet in unless the fuel screw tests indicate you need to. you certainly wont need a 27.5.

make sure all the needle retainer fingers are intact in the slide and that the retainer is not popping loose.

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Also you might look for a small ring of crud that forms around the needle right where it goes into the needle jet. That can cause an off idle problem.

not a cv carb it wont. you can remove the slide completely from a cv while at idle and it will idle all day long.

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So it turns out that the clip was already on the 4th - so what should I do now?

And it's 4th groove from the top right? Not the bottom?

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not a cv carb it wont. you can remove the slide completely from a cv while at idle and it will idle all day long.

I didn't say it would effect the idle. I said off idle problem. I see this problem quite a bit with the crappy gas we have. It will cause a hesitation just as your opening the throttle.

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So it turns out that the clip was already on the 4th - so what should I do now?

And it's 4th groove from the top right? Not the bottom?

all the spacers intact and in the correct order?

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I have the same intermittent issue, 4th clip and all but I have an open MRD/SSW. Clutch pulled all the way in or mostly in. Motor is more likely to quit when it's not good and warmed up but will still do it when hot on occasion. Has surprised me at a couple of red to green light changes when I was the 1st vehicle at the light. It won't die if I give it just a little throttle before snapping it open.

I've been chalking it up to limitations of a non-pumper carb.

ETA: It's not a hesitation but an instantaneous cut-off of the motor, I mean it's faster than flicking the kill switch.

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Thick washer - spacer - clip - skinny washer - spring - done.

Cos I was fiddling I put the clip back on the 4th and installed the 25 pilot - just to see what the difference was.

Still stalls when I open her from idle quickly - if it is just how the CV is then I guess I'll just have to be a little more delicate until I save up the money for the FCR. Should only be a couple weeks away - even though that money was meant to spent on Uni books.. LOL.

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I have never had a problem with snapping the throttle on my S model.

The little o-ring on the edge of the diaphragm cover is in place?

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Yeah it's in it's place.

I still have the problem with the 25 pilot jet - but I have to say that there is a truckload more power now! Holy hell - new bike... AGAIN!

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