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SRTchris
11-13-2011, 05:49 PM
Alright, so heres the story.

Bought this quad used, had low miles on it.
Was completly stock upon purchase. But when riding it, it had almost a "fuel cut" kind of going on when going WOT.

Filter was a little dirty. So stuck a KN filter in. Seemed like it helped it out, but it still did this cutting out. Almost like the rev limiter, but would do it randomly. Some times would do it, sometimes it didnt.

Then I bought a HMF slip on exhaust for it. Rejetted it, but still did this cutting out part.

Figured it might have been a coil going bad. Replaced the plug, boot, and coil. Still did it.

Took it to a friend of mine that worked on quads.

He rejetted it, and redid the valves.

Got it back, and rode ALOT better, but in the upper RPM range, it still had a minor cut out. But was 10x better then it was before.

So I took it back to him to check it out again. He suggested to get rid of the KN filter, thinks it might be flowing too much. So I bought a UNI filter. He then rejetted it again back to a 148 main and a 42 pilot.
I have not yet rode it, but he says it still has a minor miss up top, but it is alot better. But he doesnt want to point me in the direction of just spending money and throwing parts at it.

I asked him what he "thinks" it might be. He thinks it may be the clutch slipping in the upper RPM range, making it cut out.

Im lost, any suggestions?

CJM
11-13-2011, 05:58 PM
You will know when the clutch is slipping, you will hit the throttle and literally go nowhere.

As for jetting, 42 pilots good, air/fuel screw out 2.5-2.75 turns and if you have a uni filter a 152 should be ok.

If all else fails clean the carb well, check the filter on the gas tank petcock and finally if it still gives you issues id check the compression.

05DodgeDakota
11-13-2011, 06:13 PM
Originally posted by CJM
You will know when the clutch is slipping, you will hit the throttle and literally go nowhere.

As for jetting, 42 pilots good, air/fuel screw out 2.5-2.75 turns and if you have a uni filter a 152 should be ok.

If all else fails clean the carb well, check the filter on the gas tank petcock and finally if it still gives you issues id check the compression.

There is a fuel filter on these?

01boneless
11-13-2011, 06:15 PM
^^ yup 2 of them. a screen kfilter on the petcock that goes into the tank and a little one in the gas line entry on the carb :D

05DodgeDakota
11-13-2011, 06:18 PM
how often do yall replace them?

SRTchris
11-13-2011, 06:27 PM
Originally posted by CJM
You will know when the clutch is slipping, you will hit the throttle and literally go nowhere.

As for jetting, 42 pilots good, air/fuel screw out 2.5-2.75 turns and if you have a uni filter a 152 should be ok.

If all else fails clean the carb well, check the filter on the gas tank petcock and finally if it still gives you issues id check the compression.

air/fuel screw is about there.
The 152 jet made it worse, the 148 makes it fine.

Carb has been cleaned 5 times now, very good by both himself and i.

Ive drained the tank and cleaned that filter. I have no cleaned the one in line, I did not see one there. It just has a line from the shutoff to the carb. So I dont know where else it might be.

Compression was checked also, was fine.

When its cutting out, it doesn't do it ALL the time. Thats the weird part.

01boneless
11-13-2011, 06:47 PM
Originally posted by 05DodgeDakota
how often do yall replace them?

you dont u just clean them

CJM
11-13-2011, 06:54 PM
Needle clip is where? 3rd notch down from the flat end is what most run