Jyoung7593
PR Member
Was replacing piston on my kx450 and when I pulled off the head the exhaust valves had yellow on them. The bike did start making this knocking/clapping Noise when it would first start to run. Any ideas?
What would cause this
- Thread starter Jyoung7593
- Start date
shaffstall721
PR Member
Post a picture fool.
GeorgiePorgie
PR Founding Father
Maybe ethanol in today's gas? I run ethanol free.
ChubbyCat113
PR Member
It's not nuclear powered is it? LOL could be yellow cake 
Jyoung7593
PR Member
Where do you find ethanol free and what octane is it?
Jyoung7593
PR Member
Last edited by a moderator:
GeorgiePorgie
PR Founding Father
Chardon oil company. 90 octane ethanol free. At the pump.
Maybe buy some 90 ethanol free, there are places that sell it and add octane boost.
I cut the 90 E-free 50/50 with cam2 in my smokers.
Ahrma quick question for you: I see his other valves have a white residue, Now...does White mean slightly too lean?
Maybe buy some 90 ethanol free, there are places that sell it and add octane boost.
I cut the 90 E-free 50/50 with cam2 in my smokers.
Ahrma quick question for you: I see his other valves have a white residue, Now...does White mean slightly too lean?
Jyoung7593
PR Member
Pipe wrench was holding down white paper had the garage door open. Now if there was a coolant leak wouldn't the changing of head and cylinder gaskets fix that? Just find it odd because I haven't noticed that my coolant has been lower
Jyoung7593
PR Member
Just vp 110 fuel and Evans coolant.
premix
PR Member
There's your problem. Why are you running a leaded 110 octane fuel? Does your motor call for that much octane? Have you had your ecu retuned? (or jetting/timing set, not sure if carb bike or not). In modern day four strokes, unless you have a heavily built motor, with a correctly tuned ECU for A/F and timing, you are wasting your money running race fuel. Run 93 (ethanol free possibly, running the blend won't hurt performance for the small amount in it.)
Jyoung7593
PR Member
Just was told. Buddy put cams, high comp piston, and exhaust. Bike ran like s**t with 93 last time I used it
premix
PR Member
What year of Kawi 450? Did you have your ECU retuned?
Jyoung7593
PR Member
Sorry I thought I responded but for the valves the yellow is on the bottom then if you look in the hole where exhaust connects to head you can see the 2 exhaust valves and there is a little yellow on them as well but can't see intake valves. I cleaned it up pretty well and reinstalled it. When I started it the bikes idling pretty odd but got better then low idled and shut off. The piston that was in it was 13.5 and I went with a vertex 13.2 instead. Would that cause this much of an issue?
It's a 12 kx450. I had Tokyo mods remap it originally, but nothing since then. Think it would be running to lean? If so how do I fix that?
It's a 12 kx450. I had Tokyo mods remap it originally, but nothing since then. Think it would be running to lean? If so how do I fix that?
premix
PR Member
@ahrma479 that is some of the most backwoods hillbilly ass s**t I have ever read and 100% why I love the internet. Hopefully SuperTrapp has moved onto someone who knows what the hell they are talking about.
In the meantime @Jyoung7593 I'm going to break down the use of high octane gas and remapping for you. Your motor is set up from the factory to run properly on 93 unleaded pump fuel. Can it run on leaded 110 fuel. Sure, but a couple of things to consider. Motors built when lead gasoline was sold out of the pump regularly, run great on it and need it for lubricity reasons. Modern 4 strokes are designed around unleaded fuel and have many internal coatings only a few microns thick that will be stripped with the use of lead over prolonged use. Pretty much every modern 4 stroke dirt bike has hardened valve seats and doesn't need the added lubrication.
Now in terms of the added octane rating, unless you are significantly going up in compression or are experiencing detonation (which you shouldn't as pretty much every modern efi system has some sort of knock sensor on it), you don't need the added octane. Simply put, the higher octane, the harder it is for the fuel to ignite. So where ahrma was claiming it made it run rich, the term he should of used was "burning incompletely". Stoich levels of say 110 fuel are somewhere around 13.7, while industry standard for generic pump 93 are around 14.7. So it can be confused for running richer than pump gas without the proper ECM changes. Rule of thumb: Run the lowest octane fuel that keeps the motor out of detonation.
Onto remap why? Pretty much every modern efi bike out right now, comes mapped off the showroom floor rich. Manufactures err on the side of caution knowing it may increase engine longevity, but there are gains to be made even in stock form in terms of power and rideability. Introducing additional air into the motor (i.e. cams, air intakes) is going to throw your Air to Fuel Ratio out of whack. Enough to cause drastic issues, probably not for something like the baby hotcams, but once again, there are gains to be made when tuned correctly. And this is where Ahrma took his final tumble in suggesting if you had a carb bike to adjust your jetting and fuel screw. Tuning your ECM is nothing more than adjusting the jetting electronically. Having a properly mapped bike for your engine configuration, for a proper a/f ratio, even in stock form, makes a noticeable difference. A/F can be obtained by the aforementioned 02 sensor in the headpipe. Which not hard to buy an extra headpipe, have an 02 bung welded into it, and use something like. http://www.innovatemotorsports.com/products/lm1.php
And if you don't want to do the headpipe method, they make and adapter that fits right into the muffler (not ideal, but will get you close). And yes applying some type of load at speed is ideal. There are a few shops that I know of in Northern Ohio that have dynos that will allow you to control the load electronically.
And Ahrma, your non epa vs epa argument still has me puzzled. If you're suggesting, that just because the scooters we're racing on are non epa bikes, they shouldn't be tuned, well then I guess none of the drag bikes or cars at Norwalk should be either.
As far as tuning a stock ECU, you can have someone like a Tokyo Mods load pre canned tunes onto it, will it be right for your configuration, hard to say. If you really want to dial it in, Purchasing something like a vortex ecu, that allows for infinite tuning options is really the way to go, and there is a gentlemen right down the road, DH1 Mods (Brandon Hass), that knows his s**t on the tuning them.
Total guess as I don't know the history on the bike or every mod done too it, but if you weren't losing coolant or noticing any white smoke, my money is on the leaded high octane fuel being the culprit. Plug readings are also a good reference point to see how you're running. Post a picture of the plug.
In the meantime @Jyoung7593 I'm going to break down the use of high octane gas and remapping for you. Your motor is set up from the factory to run properly on 93 unleaded pump fuel. Can it run on leaded 110 fuel. Sure, but a couple of things to consider. Motors built when lead gasoline was sold out of the pump regularly, run great on it and need it for lubricity reasons. Modern 4 strokes are designed around unleaded fuel and have many internal coatings only a few microns thick that will be stripped with the use of lead over prolonged use. Pretty much every modern 4 stroke dirt bike has hardened valve seats and doesn't need the added lubrication.
Now in terms of the added octane rating, unless you are significantly going up in compression or are experiencing detonation (which you shouldn't as pretty much every modern efi system has some sort of knock sensor on it), you don't need the added octane. Simply put, the higher octane, the harder it is for the fuel to ignite. So where ahrma was claiming it made it run rich, the term he should of used was "burning incompletely". Stoich levels of say 110 fuel are somewhere around 13.7, while industry standard for generic pump 93 are around 14.7. So it can be confused for running richer than pump gas without the proper ECM changes. Rule of thumb: Run the lowest octane fuel that keeps the motor out of detonation.
Onto remap why? Pretty much every modern efi bike out right now, comes mapped off the showroom floor rich. Manufactures err on the side of caution knowing it may increase engine longevity, but there are gains to be made even in stock form in terms of power and rideability. Introducing additional air into the motor (i.e. cams, air intakes) is going to throw your Air to Fuel Ratio out of whack. Enough to cause drastic issues, probably not for something like the baby hotcams, but once again, there are gains to be made when tuned correctly. And this is where Ahrma took his final tumble in suggesting if you had a carb bike to adjust your jetting and fuel screw. Tuning your ECM is nothing more than adjusting the jetting electronically. Having a properly mapped bike for your engine configuration, for a proper a/f ratio, even in stock form, makes a noticeable difference. A/F can be obtained by the aforementioned 02 sensor in the headpipe. Which not hard to buy an extra headpipe, have an 02 bung welded into it, and use something like. http://www.innovatemotorsports.com/products/lm1.php
And if you don't want to do the headpipe method, they make and adapter that fits right into the muffler (not ideal, but will get you close). And yes applying some type of load at speed is ideal. There are a few shops that I know of in Northern Ohio that have dynos that will allow you to control the load electronically.
And Ahrma, your non epa vs epa argument still has me puzzled. If you're suggesting, that just because the scooters we're racing on are non epa bikes, they shouldn't be tuned, well then I guess none of the drag bikes or cars at Norwalk should be either.
As far as tuning a stock ECU, you can have someone like a Tokyo Mods load pre canned tunes onto it, will it be right for your configuration, hard to say. If you really want to dial it in, Purchasing something like a vortex ecu, that allows for infinite tuning options is really the way to go, and there is a gentlemen right down the road, DH1 Mods (Brandon Hass), that knows his s**t on the tuning them.
Total guess as I don't know the history on the bike or every mod done too it, but if you weren't losing coolant or noticing any white smoke, my money is on the leaded high octane fuel being the culprit. Plug readings are also a good reference point to see how you're running. Post a picture of the plug.
Jyoung7593
PR Member
First off premix that was awesome. I work at a hospital as an RN so I'm not to knowledgeable unless it comes to anatomy of a person so this is my hobby and I love reading about s**t that you just posted. Second off I did have Tokyo do my ecu and it seemed ok at first but at times it would act as if the throttle was clogged and they claim I need to clean my throttle body. So let's just say wasn't the throttle body. Would you suggest vertex ecu or Brandon has? I don't like to get to pricey but I'm willing to check it out. I don't have a pic of the plug I put a new one in but it was slightly grey but not at the point where it's showing hey I'm super lean. Thanks again I really appreciate the advice
GeorgiePorgie
PR Founding Father
#motoNurseProbz
I feel you.
I feel you.
premix
PR Member
@Jyoung7593. Before you go any further worrying about the mapping, mechanically and electroncially, the bike has to be in check. Lets back up to the point where you said the bike was having idling issues and it was acting like it had a clogged throttle body. When is the last time you checked the fuel filter on the bike? Would maybe suggest pulling the pump and looking at the sock filter on it. IIRC, the filter is an integrated part on the KXF fuel pumps, so if it's clogged, you're going to have to replace the assembly. Blow out your fuel lines as well. I doubt your injector is clogged, but checking it wouldn't hurt.
Secondly, electronically, you need to make sure all of your sensors are in proper working order and there isn't any corrosion in any of the connectors. You can use a volt meter to test the range on the sensors. I would also clean the connectors and put dielectric grease in all of them. One bad sensor will throw the whole system out of whack.
Lastly, and this might seem like a no brainer, make sure the bike is mechanically correct. Make sure your valves are adjusted and working correctly and the rest of the bike is in good working order. Are the hotcams a fixed gear on the cam itself or adjustable? They may need to be degree'd if adjustable.
After you can answer yes to the above 3, then lets take a look at the map Tokyo has loaded onto your ECU. I would call them and ask them what they'd suggest for fuel with the given retune they gave you before you go spending any additional money having someone retune it. If you have an issue with the above 3, it won't matter who tunes your ECU, it won't allow it to function correctly.
The mention of the bike running poorly has me thinking you have an issue with the above 3.
Secondly, electronically, you need to make sure all of your sensors are in proper working order and there isn't any corrosion in any of the connectors. You can use a volt meter to test the range on the sensors. I would also clean the connectors and put dielectric grease in all of them. One bad sensor will throw the whole system out of whack.
Lastly, and this might seem like a no brainer, make sure the bike is mechanically correct. Make sure your valves are adjusted and working correctly and the rest of the bike is in good working order. Are the hotcams a fixed gear on the cam itself or adjustable? They may need to be degree'd if adjustable.
After you can answer yes to the above 3, then lets take a look at the map Tokyo has loaded onto your ECU. I would call them and ask them what they'd suggest for fuel with the given retune they gave you before you go spending any additional money having someone retune it. If you have an issue with the above 3, it won't matter who tunes your ECU, it won't allow it to function correctly.
The mention of the bike running poorly has me thinking you have an issue with the above 3.
premix
PR Member
I noticed that too. His posts were riddled with inacurracies. He also made mention of his current or past employers where he claimed he was the main "tuner". Fuel inection systems are complex, but understanding the fundementals of an engine aren't and he made a few false statements that made me shake my head. I'm guessing he's just trying to save face. Don't know the guy from Adam, but can't say I blame him. The joys of Pitracer