Alright guys, what's wrong here?

[Stickman400]

I've been rding creeks lately and have been wanting to waterproof the 400 a little better so I put the stock lid and snorkel back on and have been trying to jet it but can't seem to get it to run at anything over 1/2 throttle without cutting out and sputtering until you let off. I tried everything from a 160 to a 180 and it did the same thing everytime. I did move the clip on the needle back up to the 3rd notch to help the throttle response since it cut out bad below 1/2 throttle on the 4th notch. I would try higher but that seems overkill with so little air it can pull in. And I would try lower but that doesn't seem advisable with my mods. So what should I try?

[400man]

sounds like its flooding itself out?? keep going smaller on the main and see if it gets better. go by how it runs, not how big you think you need the main jet

[Stickman400]

A 150 main with an 11:1 407 piston, a stage 2 HC, K&N filter and full HMF system doesn't seem like a good idea. Considering people on here are running a 155 with a stock bore, filter and slip-on. I don't think I have anything below a 160 though. If that doesn't work though I'm raising the needle back to the 4th notch.

[JOHNDOE83]

I know it sounds like it may be to little with a 160 main but it may be your option with a lid and snorkel setup.

I think you are doing pretty good and you deff know what your looking at and whats going on with it.

Anyway, your on the right track with the main try the 160 and if it doesnt clear up youll have to try the a/f screw and the needle.

I would put the 160 and test it, if it still acts up with no real improvement I would change the a/f screw, if it still acts up change the needle setting to a higher position.

I think it may be mostly on the pilot and the needle and might be flooding out before main transition, if it were happening at slightly more then half throttle I would blame the main jet.

Just to be safe, leave the 160 untill you find out whether or not its the main jet, once the pilot and needle are dialed in better I would re-jet for the main after. It sounds backwards but is probally the best course of action in your case.

[Honda5]

You need to drop back to about 145 but the HC2 doesn't work well with the air restricted like that

[Stickman400]

Yea, it's happening right at if not a little before 1/2 throttle. It tries to go, then just sputters and falls on its face. I did have the clip on the 4th notch but moved it up to the 3rd, but I think I'm going to lower it back down then mess with the a/f screw with the 160 in it. I'll report back on how it does.

[CJM]

Try a smaller pilot.

Id also do the EHS outwears style lid over no lid. I dont get water inmine at all. Snorkels plugged with a spraypaint can lid.

[Stickman400]

Alright well I went out and put the clip back to the 4th notch, cleaned the airfilter and the airbox and tried it with the 160 in and it did the same thing. I was about to give up but I decided to try one more thing. I removed the little snorkel outerwear I had on the end of it (forgot to mention that) and it ran perfectly, no hiccup, backfire or anything. But now my question is should I leave it there or maybe bump the main up a couple? I'll ride it around tomorrow and pull the plug and go from there I guess. Thanks for the responses guys. And CJM I did run just the lid and a spray can lid in the snorkel spot earlier today and it still sucked in ALOT of water and drowned out once. I think the creeks I ride in are different from what you ride in.

[CJM]

Id say new plug and ride it and see Stick.

I dont ride thru creeks all too often, I avoid water cause with no fenders it flings it into my face.

[Stickman400]

Lol. With my extended axle if I hit a water hole and nail the gas it just flings sand and water all over me, but it's hot as hell out so it's nice to get sprayed with water every so often.

[JOHNDOE83]

Yes, as long as your riding fine now throught the rpm range I would try to up the main with the jetsrus method, atleast you'll know its running good and the main jet has plenty of juice at WOT.

With no popping or backfiring you know that your needle and pilot are in a good spot, I think that raising the clip to the 3rd notch was agood thing and probally exactly where you need to be for that paticular circuit using the lid and snorkel.

Good luck, post the results in the end and add if theres any noticeable power loss?

[Stickman400]

Well I went out and chaned the oil and did a few other things to it then pulled the plug and it was black everywhere excpet the grounding strap which was a light tan almost white color. But I don't have anymore new plugs and the local shop is closed on Sunday so I wiped the carbon off and put it back in and threw a 175 in because that's what I had in it before I put the EHS lid on and it was perfect jetting. It sputtered and popped at about 3/4 throttle though so I'm guessing it's too much. I'm gunna eat and then go back out and pull the plug to make sure, then prolly put a 165 in and see what happens.

[Stickman400]

Plug didn't have much color to it but was still dark black in spots. Put the 165 in and it still sputtered at WOT. So I put the 160 back in an it ran perfect except for if I went from WOT to closed then to WOT again very quickly it wouldn't pick up until I let off and eased into it. I'm fairly positive that is the needle though.

[Stickman400]

Well I went back and raised the clip back to the 3rd notch and cleaned the carb. out and it runs like a maniac. Runs and pulls almost as stong as before, just because it can't suck in the air it wants, but it stills runs hard. I also think I fixed the weird idle issue I had from awhile back. I messed with the a/f screw and it idled percect at about 3 turns out, but it idle a little high so I turned it back down to 2.75.

[KKiowaTJ]

You also have to factor in how hot it has been in our area along with the high humidity that you can cut with a knife. I have been riding in the des moines and have noticed a power loss until the temp dropped a little.
Then again as far as i know mine is 100% stock less the pipe etc. One thing i found quick that helped in the sand creeks and river, Coat your rev box with alot of dialect (sp) grease along with any other open wire. Good luck either way

[Zakradu398]

Originally posted by CJM


Snorkels plugged with a spraypaint can lid.

and i thought I came up with something new about a month ago... :(

[CJM]

Originally posted by Zakradu398
and i thought I came up with something new about a month ago... :(


Thank slightlybent, he came up wit it afaik.