Who is using this carb ? what do you think about it? What is your jetting? I have the fcr on my Predator right now< the only problem seems to be jetting> HotSeat has way to big of a pilot jet in it and acording to Daryl Rath the main jet was to big for it. Right now I have a 45 pilot jet and a 190 main. The pred seems to Not rev up as fast as it should when driving in the mid range. I'm just saying that with all the mods i got it should be much faster then it was before.With my last mod it was almost just as fast and that was with the stock carb.The problems may be with my DYNA TEC FS It seemed that the curves I put in were wrong for the set up. Only the stock curve worked the best(I reset stock curve with higher rev limit) The other curves I had Just made it pop Like hell In mid range. Almost as if I couldn't shift fast enough. Anyone got some curves They want to send me?? I sent a email To Doug Nicholas, for his curves, so far He hasn't sent me any.Anyone have a idea? I'm going out riding now wish me luck!


Thanks
Matt Spears

 

Matt, when we send out those carbs they come jetted for sea lever with our 600cc kit. But it doesn't sound like it was too far off from were you are at right now jetting wise. From what you are saying my understanding is that it's just really flat in the mid? Is this with the stk. curve even?

 

Matt........

I don't know if you have tried this yet, but talk to Ernie660r.........he is the one who pretty much started with that carb. He knows a lot about it, and last I knew he has an aftermarket cdi too.......so you might get some useful info from him. Otherwise, I was thinking there was a "sticky" note on the pred owners site.......that told a lot about the carb, and how to jet it for different applications. anyways, Good luck.........jetting sucks........


In my opinion, and I haven't been around quads in a while, so I'm kinda out of the loop.......and I also don't know your mods(would be nice to know in your sig......show 'em off)........but I'd go with a 50 pj and you mj sounds good........what is your needle set at??


Brad

 

well, the predator was a mess,the jetting must be wrong and so are my timing curves. I tried the stock curve and it was the best,but the pred was slow. I think I could have beat my pred with a stock one,as a matter of fact i got beat in a drag by a z400 and I NEVER LOST TO ONE BEFORE!!
The pred wouldn't rev up fast,what I mean is it would take forever to climb though the gears. Starting in frist it would rev though/ into 2nd fine but after that it fell on its face.it was flat for sure ,in the mid to the top .It seemed to miss/pop alittle sometime while pinned in third though forth.Once i would finaly get enough rev out of it to go into 5th,it just wouldn't rev though it.It just would bog though 5th and never make it all the way to the top.When i would try to drag starting in 2nd to would bog.
as of right now I have a 190 main jet,the needle is in the 5th clip spot from the bottom(leaner) and the pilot is a 45.I feel that maybe it is rich on the main jet,but last time i pulled the plug it was grayish.It still has a alittle problem starting when hot and it seems to get hot quick.If i dumped some water on the head pipe it would just bonce off it was so hot,i even got burned by riding though a puddle.
I am pissed to say the least Because I put almost 5000. dollars into the engine and it is slower then stock.The only good news I have is the hinson clutch held up great,I even Put on my maxxis roosters and power shifted it hard to see if it would take it and it just shifted awesome. What do you guys think! i think it needs a smaller main jet but i am afraid that it will run to hot.Can it run Hot if it is to rich?

Anyway, I will be taking it into the dealer And hopefully we can drive it up to Eastcoast ATV To dyno it. I still need to Talk to Daryl Rath about some Curves for the Dyna tec. Anyone got curves?

 

Did you change cams are they out of time? Maybe one of the gears on the cam started to move or spin had it happen to a guy last week.

 

The cams are custom WEB CAMS. I'm not sure of the specs though because I can't remember, But I can get that info from my dealer, Atlantic polaris, they have all my paper work on this engine. It is good to hear you say that it could be the cams Because I figure that if it wasn't the jetting or the timing curves then it has to be the cams.
I'm pretty sure the cams are stage two with a longer duration on the exhust But I'm not sure.

 

Matt---

If your pred is out of time, it could be both running like crap and gettting hot. That would be the first thing I would check before riding again.....you are messing with timing curves, and aren't for sure if your motor is even in time.......You know how to time it right?? If not, just ask.......I somewhat remember, but someone surely will..........Oh......one more thing I was thinking about, I don't know the state of your motor......so correct me if I'm wrong, but do you have too much motor, for the carb?? In other words, do you need a bigger carb?? About it getting hot, if it is in time, and isn't running really lean........then I'd reckon that its just the rath head pipe. Have you ridden with the head pipe before, without the motor work??? I've heard it gets really hot, that is why guys are getting heat shields from them made.


I don't know if you found that page on predowners or not.........but some of them suggest a 52 pj.........say 190mj is too rich........and suggest 4th clip on needle(also suggest the HRC carb kit too)........They also say the carb is very touchy on intake setups.........saying to use about a 3-4" tube before the carb(so not a direct clamp on)........

I don't know......but I'd read that page if I was you.......very helpful......

450r carb tuning


Good luck Matt

 

My set up is all new, the whole engine was rebuilt. When i was building the engine I talked to Rath about carbs(had problems with hsr/hpd carb) I asked rath Which carb to use with my set up(since it was about the same as he once used) he told me to use the FCR 41mm. I don't think it's too small even if it is smaller then the stock carb. The fcr just so happens to have more cfm's then stock, It was right on with what my engine needed in cmf.
I did use the rath pipe on the stock engine and yes, it did run hot. I welded on nuts so i could use my stock heat sheild.I'll have my dealer/sponcer Check the timing tommorow//they owe me !!
Just so you know the engine has a falicon crank /FULL MOD/ 560/ 13:5:1 piston/ 3 angle port job with 1mm oversized stainless valves and ti retainers.
As for the pilot jet a 52 was way to big, i couldn't start the engine when hot and turning the screw did nothing.Also with the 52 I had to turn the idle screw all the way up just to idle. I dropped to a 45 and now it idles and starts better but not perfect.The air fuel screw is only a turn out and it still seems as if it doesn't work unless all the way in(i might want a smaller Pilot?)If I pull the choke It idles faster amost as if the pilot is lean ,this has me confused.i would think that if it was to big it would shut off because of flooding.Who knows,I think the pilot is real close though(1 way or other or just right)
as for the rest Daryl Rath told me to use these jetting specs;;40 or 45 pilot, needle in #4 and 170 to 178. those main jets seem to lean but I haven't tried it yet. Hotseat sends the carb out with a 55 pilot and a 185 main with the clip in #5. It just sound risky to go from a 190/185 down to a 170,172,175 or a 178. what do you think? should i try it? My spark plug is GRAY . What the hell is gray tell ya, I only know white(lean) brown(good) black(rich) whats gray mean?

 

I dunno about gray........sounds almost like it was rich......and it is begining to turn lean? I dunno.....never seen gray lol.......I do know though, to check ur plug, I've heard you are supposed to use a magnifiying glass and look down in there a ways to tell the color.......I personally don't do this, but I'm not trying for max hp either(got this info from polarisbob)..........I know going down a clip on the needle should make it a little more lean too.......I wouldn't go down a clip and a lot of mj at the same time.........might be too much.......I'd go down the needle to clip 4, and maybe go down to 180ish to start, then work your way down.......I guess on your pj......if it idles good, and runs good from idle to about 1/4 throttle, then it is probably fine.

Did daryl say he ran a stock 41mm carb or was his bored out?? Did he run that needle kit?? Also what filter setup did he run(this might be useful)......looks like you are running the cfm airbox.....??.....If so, I've heard they make jetting very hard.......and aren't worth it......tell me what filter setup ur running if ya get time.


Sounds like you have quite the motor there......good luck with it, when you get it running.......better buy some new grips!!!!

 

Matt, have your dealer look very close to make sure your cams havn't spum its hard to sse if they havn't seen it before, easiest thing to do is get a set of stk. ones and set them side by side to check it out.