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2008 KFX450R, CFM intake, HMF slip-on, Powerbomb header, Procom, Rekluse Clutch, Stage 2 Hot Cams!!!
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Discussion Starter · #1 ·
I have a 2008 that I made some engines upgrades and now take some time to start. The machine was starting right away with no issues with the following settings: FMF Power bomb / HFM Slip-On / CFM Intake with UNI Filter / Procom Map 7.

Just service/refresh the top-end with new piston 12.4:1, Stage 2 Hot Cams (Shimmed to Hot Cams specs), new steel valves and springs, new timing chain, new timing chain tensioner, ported the intake/exhaust head sides and set the Procom to Map 9. Before the top end was dismantled, I noticed the timing was off one dent (28), while the service manual stayed that should be 29 dents. Like a stated above I have not noticed any big issues with the machine other than a little to the rich side (pictures below).

Spark Plug before New Top End
Hand Automotive tire Automotive design Motor vehicle Gesture


The issue that I have now is very hard to cold start and in some instances at normal running temperature. I took the machine for break in the new piston, probably 1 hour ride. I pulled the spark plug and noticed that now is running way to lean (pictures below). The big changes done to the engine/ECU other that the new parts was the timing adjusted to OEM specs and Map 9 in the Procom.

I no expert with the the Procom programing, but it could possible to adjust the timing and input of gas via a custom map? How user friendly will be the Procom Software?

Any advise with the hard starting and the lean spark will be really appreciated.

Spark Plug after New Top End:
Gas Nail Eyelash Wood Human leg
Automotive tire Finger Gas Thumb Nail


Thanks in advance!!!

Hand Automotive tire Automotive design Motor vehicle Gesture
Gas Nail Eyelash Wood Human leg
Automotive tire Finger Gas Thumb Nail
 

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Welcome to the Forum...!!!

Make sure your battery is fully charged 12.8v standard..!

Make sure all your sensors are connected...

Is your TPS voltage in range...see pic

Can you do a compression test? 49~81psi useable.

I'm wondering if the rings & valves seated properly...If it's all good..!

Check your fuel pressure 43psi

Also a faulty water temp sensor could cause you problems
 

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Registered
2008 KFX450R, CFM intake, HMF slip-on, Powerbomb header, Procom, Rekluse Clutch, Stage 2 Hot Cams!!!
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4 Posts
Discussion Starter · #3 ·
Welcome to the Forum...!!!

Make sure your battery is fully charged 12.8v standard..!

Make sure all your sensors are connected...

Is your TPS voltage in range...see pic

Can you do a compression test? 49~81psi useable.

I'm wondering if the rings & valves seated properly...If it's all good..!

Check your fuel pressure 43psi

Also a faulty water temp sensor could cause you problems

Thanks Dust Devil for the prompt response!!!

Make sure your battery is fully charged 12.8v standard..! - Battery fully charge!!

Make sure all your sensors are connected... - All sensors are connected!!

Is your TPS voltage in range...see pic - I will verify voltage during this weekend!!

Can you do a compression test? 49~81psi useable. - I will verify compression during this weekend!!

I'm wondering if the rings & valves seated properly...If it's all good..! - All 4 valves where sure to be perfect seated (even water test was made and no leaking with only finger soft pressure) as well as the piston rings / DOUBLE CHECKED!!

Check your fuel pressure 43psi - Will need to buy the pressure tester.

Also a faulty water temp sensor could cause you problems - I replaced with an OEM sensor a year ago as suggested by "Duster" for the fouling sparks plugs (sorry didn't mention before) while I was looking into the "richness" issued. The spark plugs where not fouling but as you can tell by the picture the engine stay a little too rich.

The engine some times even start with no issues cold or warm. I get the sensors, been reading trough out the blogs and I get it. But is the timing will not affect the way the engine will start? I have the machine for over two years without opening the top/lower end and no cranking problems at all. Now that I noticed the timing was off by one dent is having this issue. Again not saying that a sensor and/or voltage issue, but I was wondering if delaying the timing within the Procom can resolve it.
 

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2008 KFX450R, CFM intake, HMF slip-on, Powerbomb header, Procom, Rekluse Clutch, Stage 2 Hot Cams!!!
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Discussion Starter · #4 · (Edited)
A little story to tell. I went to my riding place (CROOM in FL) today, the machine was not a 100 percent starting but I have to go!!! Well after the first ride (45 minutes) return to camp and the machine didn’t want to start at all, until battery was drained, so I thought is was that. Went a get a new one, since there is a bike shop at the entrance of the park. No good the same freaking issued of hard starting. One of my buddies ask to me check the left side of the engine so I removed it. Limiter gear broken and one way bearing stock!!!! Lucky enough the bike shop have the limiter and I was able to repair the one bearing with a spring from a friend dust cover bearing since the bearing it self was not damage just the spring. Drained oil, clean all the debris from the broken gear, put everything together and still the same but the engine was turning smoothly. I has power, gas (injector) was spraying, spark so everything check out but no luck. By chance a friend have an extra ignition coil from a Suzuki and……you bet!!! The freaking coil was busted. It did not safe the date of riding but at least the problem has been resolve. What coil you guys recommend the OEM or an aftermarket?

I download the Procom software but I don’t see any pre load maps. I connect the Procom as directed in the software manual and no luck either. I can see any maps at the software. Do I need to have the ecu connected to the machine to be able to see the maps?

Thanks again dust devil!!!
 

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Hey buddy I had close to your exact mods and had the EXACT same problem! I used every preloaded map along the way and found that map 9 was absolutely the worst for cold starts and stalls. I started experimenting with maps to improve the starting and i got it start a lot better if you'd like to give it a try! You'll have to remove the ".PDF" from the file name. I couldn't upload it without making it look like a common PDF file lol.

Another thing i used to do to help starts with the Procom was dump a quarter throttle for the first 2 crank-overs then let off and it usually jumped right up even cold. I hope this helps!
 

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