It seems awful big to me, too. I ordered a kit from Hetrick. They sent me a 120 and a 125 main. I am not a big bore, it's the stock cc. I just thought I'd start with the larger jet and lean it to the 120 if the plug looks black or it fouls out. In the cul-de-sac in front of our house I had my 11 year old ride it (after me of course [img]i/expressions/face-icon-small-wink.gif[/img] !!!) and he was putting around. I asked him to give it some throttle so it reved up a bit more. I stopped him and said "Are you going full throttle?". Keep in mind, my older boy is very conservative. So I talked him into going full throttle. Holy cow-As soon as it hit the power band he was at the end of the street, and I mean RIGHT NOW! He had to let off. It took off like our little mini never had.
I'm getting ready to pack up now-looks like Baseball rained out, so we'll be leaving today instead of tonight. I'll keep you posted.
Be back Tuesday.

Jesse

 

It's important to note, that some of us want more low end power for different reasons. I need more slow and go power to negotiate trails with rock. I can't go fast over that stuff. Mine is a gearing issue, verses a high take-off speed at the low end, IMO. It sounds like you've made some great mods.

 

If it was too rich, I don't think it would run. Mine falls on it's face with a 110.

The only thing I can figure is my pilot and needle are making up the difference. Dunno.

 

If the thing is falling onits face then its to lean. I might have mine over jetted alittle but I've had it it out twice now that the snow is gone and no problems.[img]i/expressions/face-icon-small-smile.gif[/img]

 

They'll fall on there face either way. Lean or rich. That's what I meant when saying the jetting is very sensative.

 

also on the stock carb with a uni or k & n. if you add a pipe and higher compression you will have to drill the float seat out bigger. the quad will scream for a few seconds then fall on its face because the float bowl has drained and the small orfice in the seat cannot fill the float bowl quick enough.

Mark

 

OK everyone, I'm back from Glamis and here's the report...............
The pipe Hetrick sent me was the "Koso" pipe. First rides, we went with the 125 main jet. Ran and idled fine, but a little soft on the bottom. I switched it out with the 120 main jet and it seemed a little better. It rev's WAY higer than it used to. After running about 5 gallons of fuel through her, the plug had a nice light brownish look to it. Nice snappy throttle, and it did not bog down on those sand hills. It is still soft on take off, but I have some more tweeking to do on the rear clutch pack. Over all I am very happy with the improvement.
Also, wide open for a mile at a time (literaly), this unit did not starve for fuel with the stck 18mm Mikuni carb. I did not drill out the needle and seat. Flows fine for me. I am going to try a set of paddles after Easter to see how it will pull those.

 

I am in the middle of rebuilding the top end of my 2 pred 90,s. I also had .050 taken off the top of the cylinder,s and did a little porting job. The quad,s already have uni,s Hetrick clutch kit, f.m.f pipe,s oil injection removed, I can,t remember the jet size right now, we will be going to Ocotillo Wells next weekend and try out the improvment,s.

 

Are those viper 90r's you'er talking about Knowpig and if so did the exhust bolt right on with out changing or moving a lot of stuff/

 

I know ho restrictive the stock airbox is on the vipor/predator/eton 90's, but does anyone make a better airbox/filter that can handle
all the water and mud we go through when trail riding??? You know your boy's never listen when you tell them not to walk in the
mud puddles with their new shoes on... Just think how it is with his quad!!![img]i/expressions/face-icon-small-happy.gif[/img]