new fmf gnarly install and results/questions

minidog

Member
May 18, 2002
43
0
2002 kdx 200-stock engine-just bought fmf gnarly and did the insallation-fit just like a glove-was really worried about this before purchase-got a good one I guess-using stock spark arrestor-cranked bike for first ride and loved the new sound-very raspy but not too loud, sort of like a snare drum-power was very, very good-has a great surge at mid range-this thing was bringing front end up during hard acceleration in fourth gear! when I did the install I put on a freddette exhaust ring-now heres my questions. trying to zero in on jetting this thing-have read numerous posts and the technical advice and recomendations on canadian daves tech section and this problem really has not been found-I guess this relates to my bike only-temps. at 75-low humidity-mobil mx2t at 40-1-155 main, needle in mid clip, 45 pilot a.s. 1/2 turn out-when in second gear going very slow(crawl speed)roll throttle on and power comes on slow then takes off-my problem is in a.s.- pilot area- I try to adjust a.s. out 1/8 turn more and get a bad bog off idle-I cannot go beyond 1/2 turn out without bog so this tells me to go richer on pilot which would put me at stock 48 pilot- can now take a. s. out to no more than 1 turn which is where i should be but bike is still slow to respond right off idle and now im getting totally black plugs-opinions,comments please-have tried 42 pilot before with real bad bog-cant adjust out of this with air screw-just did top end, cleaned power valve, thinking maybe some boysen reeds might be solution to the crispness that im looking for- stock reeds look just like new-air filter clean with no air leaks anywhere-thanks for replies
 

h2oskibilly

Member
Feb 17, 2003
7
0
I have a KDX 200 2001 model and I'm having the exact same problems with the jettting issues. After changing the pipe and removing the airbox lid I started with a 155/42 running the needle in the center clip position. I have adjusted and adjusted the airscrew with no real luck. I get the same bogging on the low end throttle. I actually went on an all day ride yesterday and got myself really confused. I thought with this set up, if anything I would be on the lean side, but by the end of the day my pipe had plenty of black goo coming out the back and I had numerous people tell me it seemed to be running rich. I obviously can't help you with your problem, but I'll be watching to see what responses you get so hopefully I can learn to. I'm really at a loss right now.
 

Robcolo

Member
Jan 28, 2002
342
0
Many people don't like the stock needle. I believe a CEL will crisp up the entire range. Do a search on needles and/or RB Carb mods.
 

minidog

Member
May 18, 2002
43
0
this sounds like a good idea with the cel needle-looking now for info on it-will definately be trying one soon-even with the stock pipe I was having same problem with pilot and air screw-48 pilot was way too rich but could adjust air screw out to about 1 turn- but beyond that would produce a lean bog-would get a lot of black plugs and some times fouled ones too-dropped to a 45 and this solved fouled plug problem but could only get to 1/2 turn out on air screw which I think puts me at minimum on adjustment- have gone to a 42 pilot which really makes this thing bog bad even at 1/2 turn out on air screw-friends watching me ride bike say it produces some smoke with 45 pilot-have tried adjustments on needle and main as well-clip in second from top on needle- produced lean bog at mid throttle with some smoke-tried 152 main with noticeable drop in power-so here I am with 155 main, needle in mid clip position, and pilot at a 45 and air screw at 1/2 turn out and thats as far as I can take it out-not even another 1/8 of a turn-what gives? bike smokes a bit and even produces dark brown plugs at current settings but acts as though its running lean-going to check out this needle thing for sure-where can I get one-any more suggestions or comments would be appreciated
 

Robcolo

Member
Jan 28, 2002
342
0
as far as smoking goes, IMO, 40:1 is too rich. I've gone to 60:1 and it smokes way less. I'm running a synthetic / mineral oil mix 50:50.
 

fuzzy

~SPONSOR~
Jul 26, 2002
447
0
I would advise to do a search on oil mix before heeding this advice. A properly jetted bike can run 32:1 or even lower w/o fouling plugs in the woods. It's all personal preference, but I prefer smoke over blown eninges.
 

minidog

Member
May 18, 2002
43
0
yes, I tend to agree about the mixture with fuzzy. really dont think my mixture is the problem but sounds to me like some sort of an air leak in system. bike runs o.k. with 45 pilot in it with air screw at 1/2 out -just dont have any adjustment with the thing is all
 

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
0
Set your main first.

Check this. (if you haven't already)

...note skipro's, 'Sounds like you could go leaner in all the circuits, but start with the WOT and get the main right..'

Yup. Get the main right.

You will very likely get something other than a 155 (lower/smaller).

Then, just for fun....try the AS further out than what you've decided is max. Find a bit of a load (gradual incline) that you can run over repeatedly. Turn your AS out 1/8 of a turn at a time, say, out to 2 1/2 or so.

I'm assuming a number of things...clean air filter...decent fuel....KIPS working properly.....a top-end that didn't need to be replaced last year? Probably not on an '02. Still possible, though.

This is a new-to-you bike? Or you bought it off the floor?
 

minidog

Member
May 18, 2002
43
0
brand spanking new off the floor in fall of 2001- only problem with wot chop is finding someplace large enough to do it-will make this my number one priority now-have read and reread posts on jetting and took recomendations as my starting points on needle and pilot-have gotten really good at the feel methods on these circuits- I thank this site for that- this is why Im kind of perplexed with this problem -will get back as soon as possible on wot chop-actually have installed a 152 main in past and didnt like power delivery(noticeabley down on power)
 

minidog

Member
May 18, 2002
43
0
still have oem muffler-only possible problem with it is that 2 months after purchase of bike I totally drowned bike (and myself ) in a creek-bike was totally under water-never replaced packing material or purchased aftermarket muffler - just let it dry on its own- air filter always kept very clean especially in dry dusty conditions- oil it wilh bel ray air filter oil with a small amount in palm of one hand and spread evenly over entire filter-then wipe any excess off with clean paper towels- try to get as much oil off as possible-apply grease to lip of filter at seal.-elevation is very near sea level-richmond ,va.-low humidity temps around mid 70. checked reeds, kips valve two weeks ago, top end checks out good.-will fiddle with jetting some more
 

canyncarvr

~SPONSOR~
Oct 14, 1999
4,005
0
There is no packing in the oem unit to check. It didn't get hurt getting wet.

But.....your engine? That's another issue.

How have you determined that the topend is ok?

Same question for KIPS. How did you determine that.

Good chance the drowning did some damage.

The response you are getting from your bike is not normal. If a reasonable jetting approach doesn't resolve the response of the bike....I'd have to wonder about the drowning part.

Sorry 'bout that.
 

Braahp

~SPONSOR~
Jan 20, 2001
641
0
Did you remove the bolt and drain the oem muffler? I crashed in a creek once and boy was that muffler full of the nastiest, oily water you ever seen.
 

minidog

Member
May 18, 2002
43
0
when bike got drowned heres what I did- drained carb and tank, took off air filter and cleaned, pulled spark plug and cranked engine over gently by hand to get water out, drained oil from transmission and refilled with fresh oil, installed new plug, drained expansion pipe and reinstalled, and it fired right up, changed motor oil again after a short ride. -bought service manual about 2 months ago because I wanted to see what was going on inside engine (kips mainly)-studied manual for a few days before going into top end and did my measurements on rings, piston and cylinder and everything was well within specs, kips was a little gummed up and it cleaned up very nicely-did notice some carbon build up on top of piston and cleaned it up-cylinder walls had a few scratches near bottom on intake side but that cleaned up with a little emery cloth-same thing with piston on lower end of intake side- took my time putting everything back together and bike perfomed good with same problems with airscrew-cant go beyond 1/2 turn with a 45 pilot without getting a small bog. oh well guess Ill ride it like that-Ill keep working with it and post any findings that I come across-thanks for all the replies from everyone
 
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