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Discussion in 'Dakar champion (950/990)' started by Gixxer2go, May 16, 2005.
Can somebody point me to right direction? When opening full throttle at low/mid rpm I got a little hesitation before acceleration. It appears more when engine is hot. High rpm, low speed etc seems to be ok. What should I change (if at all)?
950SE, sea level
SAS, EPC removed
Acras w/ inserts
snorkel removed + sommer door, no prefilter
MJ 165 front, 170 rear
Pilot jet 45
Factory Pro needle @ 4th clip
fuel screw 2turns
fuel mileage around 30-32mpg or 7.5l/100km
I suspected it's a bit rich and tried also 160/165 MJ, needle in 2nd and 3rd clip - that's made things worse, bike runs hot (often 5bars in the city) and power was decreased. Now I suspect I should change back to original needle. Any more ideas to prevent this hesitation?
I spoke to Marc too when I was setting up my bike for the same type of high humidity environment, myrtle beach SC. I'm using bigger mains, 170's, and stock 42 pilots. I have floats set at 3mm, screws a little more than 1.5 turns out and FP needles on the 2'nt clip. It runs pretty good.
my set up was waaay rich of idle with the 45 and 2 on ims. like 8% co rich. I went to 100/70 air jet's and 1.2 out on the ims and a lot better now.
Also, i dont trust the FP needle..
Whole diffrent set up thoug.
on the 950 i was at 0.9 out on the ims, 80/70 air jets and 45 pilot's.
It is going to run five bars in city traffic..
You are to rich on the pilot with the screws at two turns, two to two and a half would be good with the 42's..
The CV carbs need vacuum created by the air box, try replacing the sommer door with the OEM one with the snorkel removed then try the sommer door with the snorkel in..
Mine did not like the sommer mod or the 45 pilots..
Try these to fine tune your pilot...
If you read the tuning instructions they point to the float height for 3k rpm bogging.
Sounds like you are also rich on mix screws and needle clip and maybe mains. 1.5 and 3 for sea level. What is your altitude?
I don't rember which way the instructions said to go with float height if worse when hot.
I set up another 950 the same as mine except for the float height @3mm and mine is a bit more snapper. He had 165 and 170 mains and was fouling plugs.
Following the steps the FP instructions are a PITA but your are just guessing if you try to change all the seting @ once. I gleaned what I could from the matrix, called Marc and took my best guess because the Adventure is such a PITA to undress. If I had a SE and some time I think I would do it step by step.
or you could save yourself lots of aggrivation and time and just get a kit that actually works according to its instructions
Contrary to some, I am very happy with my FP setup.
Looking at yours, I would go back to the 165/170 mains, needle at #3, leave 45 pilots in, screws around 2.0, floats at 3mm, I would put the stock access doors back on or otherwise seal up the sides of the air box. I have not fooled with the air jets. I run mine stock with this setup. Have you redone your carb vents per the TSB? Extend 1" below bottom of airbox into V between cylinders. Do not tie together. I left my snorkel in. No prefilter. Mine runs very strong with this setup and makes 40 mpg.
I just happened across this thread and thought I would add my 2 cents. I just got rid of my 98 Suzuki Bandit (want to get a DL1000 next year) and I had tried a FP jet kit in it. I fiddled with that thing for 2 years trying to get it from running too rich. I know others with the same bike and jet kit that had the same problems as I did.
I don't want to brag, but I want to lend some credibility to what I am about to write. I am a test engineer for NGK and have years of motorcycle and automotive carburetor experience. I also had an NGK AFX wide band A/F meter on my bike. I couldn't bring myself to believe that Marc's stuff could be so far off, but I finally narrowed the excessive richness to incorrect needle diameter at the root (too small). The thing was just so rich (about 10:1, not to mention the poor mileage and black engine oil) at smaller throttle settings and there was nothing I could do to counteract it. I eventually went back to the stock needles and just used the stiffer springs that were in the FP kit. It was perfect after that.
I think part of the problem is that Marc focuses on the WOT & upper rpm performance and doesn't check enough for real-world driveability. He does not use an A/F meter when developing his jet kits - he uses a 4/5 gas analyzer and tunes to a certain % CO.
The following is a quote from the FP webpage: "If 5% CO made best power at some rpm and throttle position, you could also tune all other throttle positions and rpms and even idle to 5% and you'd have a nice, smooth running engine." This reasoning is faulty. For example, let's say that 5% = approx. 12.5:1 at WOT. Even if 5% did not = 12.5:1 at lower RPMs and throttle settings it most likely would still be too rich. A rich mixture such as 12.5:1 does not give you "best power" at idle, part-throttle cruise, etc.
Automotive manufacturers use both a gas analyzer and wide-band A/F meter for developing their engine calibrations. The key is to initially tune to best power and torque all across the board regardless of the A/F mixtures. Not just tune only to best power at WOT & max RPM.
I'm not saying that you should tune to a specific A/F ratio but you should use a A/F meter as a reference to verify that you aren't too rich or too lean in certain areas. This is where I believe Marc at FP has missed the boat. Sure, his jet kits work good on the racetrack but not around town.
If you can't get rid of an overly rich condition when using an FP kit then I would suspect that there is a problem with the needles.
Anyway, my 2 cents worth.
You may or may not be correct about FP's approach. I can't say. I think it might be a little unfair to speculate without giving them the chance to respond. In my view, and I've been at this tuning business for over 30 years, the proof of a setup is in the way it performs under real world conditions. If you couldn't get something to work on your Bandit, I respect that. My real world (not dyno, A/F or race track) experience with the FP kit on my 950 SM, has been very different over the 13,000 miles I have on the bike. As I said earlier, great performance, no flat spots or surging and 40 mpg.
I didn't give the whole story. I could have mentioned that I communicated back and forth with Marc at FP and he could offer NO explanation. He didn't care about me because I was just one person questioning and complaining.
I didn't speculate that his needle design/quality was bad for the Gen1 Bandit jet kit - I proved it to myself and some other guys with the same bike & jet kit - the performance under real-world conditions was very poor.
I'm glad you are having good luck with your bike. I'm just throwing this info out there to maybe shed some light in case some people are wondering why they can't make their FP jet kits work like they should.
By the way, is 40mpg considered good for your model? (I can only wish that I had a KTM 950 so I don't know.) I gained 5mpg (37 to 42) after going back to the stock needles on my old bike - just the needles = 5mpg... too rich.
I am not challenging your experience with your Bandit. I am just saying that the "too rich" problem you had with that bike is not, from my experience, transferrable to the KTM 950 as you so strongly say ("FP No Way!!")
To answer your question, I think 40 mpg for a 950 is pretty good from what I've heard and read. But it has to come with great performance and ridability, which it does.
I'm not selling anything here--just looking for some accuracy and fairness so people have the best info to evaluate and make their own decisions.
Yes, I agree my 'no way" may have been too harsh...
But as I read thru some of the old posts I saw more than a few comments and descriptions pertaining to overly rich conditions. I guess your experience is good, but there are many other people that experience richness when using FP kits - and it's not in their pocketbooks.
I may not be fair - but based on my experience - I think Marc's tuning methods have some flaws when it comes to real-world driveability. And I don't trust that all of his jet kits will have good real-world performance.
Anyway, I ranted and raved enough. I just get worked up because I got shafted with my jet kit.
Fair enough, I guess? I have limited my comments to what I have tried and personally evaluated, at length, on the particular bike that is the subject of this thread. Extrapolating from my experiences with other bikes or from my interpretation of what I have read of others' experience with the FP needles KTMs is just not something I think is appropriate.
But everyone is entitled to their opinion.....
I realize that this thread is to share experiences jetting carbureted KTMs using an FP jet kit. Granted, I don't have a KTM, but I had a motorcycle with carburetors that I was trying to jet using a FP kit. I am not really "extrapolating" anything. Those other guys in the old posts described that they were having the same exact "too rich" issues using a FP kit with their KTMs as I did with my Bandit. They also described using A/F meters on their bikes and finding that the the FP set-up was too rich. Same as me.
My point is that I think that Marc's tuning theories are a little off kilter when it comes to tuning to a % CO. I think he ends up too rich for real-world operation. I also tend to believe that people often put in the FP kits, get it running good enough, and then leave it at that. What if the bike could be tuned better than that? Don't most people expect that if a company makes a jet kit - then it will make their bike perform better - and also operate correctly? A 10 ~ 11:1 A/F at cruise is not correct.
What if you could get a few more MPG if you used the stock needles and did some tweaking with a A/F meter as a reference? Wouldn't you think "Crap, what's the deal?" "Why didn't FP figure this out?" That's what I did - and said. It seems like some of the old posters might have realized that too...
Look, I was just responding to a guy who already had the FP kit and was asking for help. I didn't start out pushing the FP kit or knocking any other kit or approach. You found a convenient soapbox and jumped up on it. While I doubt that it matters to you, I have tested with the stock needles and with FP extensively. I have never just settled for something that barely works. I will still try changing air jets and other options too. I have followed this thread from the beginning and learned a lot from the varying views in here. If I have a preconception, it is that a some guys are looking for a quick fix and don't work through the steps logically to get their bikes properly jetted.
Still just my opinion....
"If I have a preconception, it is that a some guys are looking for a quick fix and don't work through the steps logically to get their bikes properly jetted."
You're absolutely right.
And for the guys that have put the time and effort into it and still can't get it to run right, I am letting them know that a few people have evidence that some FP jet kits are not properly developed/engineered. They can move on and know that it's possible that their kit is the same quality and their bike may never run right with FP's needles.
"I have tested with the stock needles and with FP extensively."
You shouldn't have to do that - that is FP's job! Did you spend a lot of time fiddling with the FP stuff? Was it because it didn't run right with FP's recommended settings? You wouldn't have been the first one.
I have often wondered if they take enough time in their most likely rush to develop a jet kit for a new model. FP offers jet kits for a lot of different bikes. And when you call them for support, and they can't figure it out, they ultimately just say "good luck"!
I know - whatever - right?
the simple fact remains that the kit just does not work. Yes you may be able to tweak it to get your bike running but you are entirely on your own. It is a scam.
I see now. You guys don't want a kit. You want a prescription-a one-size-fits-all fix that requires no thinking on your part. Next time someone writes in asking for help with their FP setup, I will just tell them they are stupid and to throw the kit in the trash. Sorry for trying to help. The soapbox is now all yours!
People just want a kit that works as advertised. Many people have invested serious time and money trying to make their FP kits work. Marc at FP needs to do the same before pedaling them.
Everybody appreciates the help that they receive on these forums. Nobody has a beef with you. I'm just sharing my experience like you were. Don't be mad please.