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Posted: **Sat Jun 13, 2020 5:02 am**

Hey guys,

I have a bike that I bought not running, and did some work to get it where it is today. However, the bike will not kick start, only bump start. Verified timing and valve clearance dead on. Seems to be a fuel issue. When bump starting if you let off less than 1/4 throttle it will instantly die, and never idle. First I checked the fuel pump filter and found that it was missing. Added a new one in place. Disconnected the condenser and applied 12V to the connector. Fuel pump ran, however I have no way to determine if fuel pressure adequate?

My thoughts at this time is a weak fuel pump, bad/clogged injector, or internal failure to stator not supplying adequate voltage to the pump? any thoughts?

Posted: **Sat Jun 13, 2020 8:55 am**

Welcome to the site !! $\:D/$

The 09 had known fuel pump issues and they put out a Updated one , if this pump is original , then it is possible the issue (not 100% , but most likely) is the pump

https://www.crfsonly.com/catalog/produc ... ts_id/3959

However , It could also be a clogged injector , Motion Pro makes a tool to clean them , it isn't cheap
, but it will save some money (in the long run) from replacing clogged injectors , which are not cheap .. Replacement Injector: https://www.crfsonly.com/catalog/produc ... ts_id/4107
.

Injector Cleaning Tool
https://www.crfsonly.com/catalog/produc ... ts_id/5633

If you have already done the filter ,then you eliminated that as being the cause ... now with that said ........

IMPORTANT:
Now , there is one other thing , and going by your symptoms of it running at higher RPM (which would really kind of eliminate fuel pump) , would be the ECU/ECM , if it is bad , it likely could give crappy performance at lower RPM's and run at higher RPM's , unfortunately , they are not cheap , OEM is in the $400 range , and aftermarket can go as high as $1000 ..... You might try EBay , and look for a used one , you can get them fairly cheap there , and if it is the issue , it will be a much cheaper alternative than buying new ..... , and unfortunately , there is not really a way to positively test the ECU if the bike still runs at higher RPM , but lacks lower RPM power , there is no "test" for that

Posted: **Sat Jun 13, 2020 10:14 am**

I agree with Jim's analysis. Try the simple thing first. Plugged or restricted fuel flow, then weak fuel pump, then plugged injector, then ECU.

Posted: **Sun Jun 14, 2020 12:14 pm**

Welcome to the site !! $\:D/$

The 09 had known fuel pump issues and they put out a Updated one , if this pump is original , then it is possible the issue (not 100% , but most likely) is the pump

https://www.crfsonly.com/catalog/produc ... ts_id/3959

However , It could also be a clogged injector , Motion Pro makes a tool to clean them , it isn't cheap
, but it will save some money (in the long run) from replacing clogged injectors , which are not cheap .. Replacement Injector: https://www.crfsonly.com/catalog/produc ... ts_id/4107
.

Injector Cleaning Tool
https://www.crfsonly.com/catalog/produc ... ts_id/5633

If you have already done the filter ,then you eliminated that as being the cause ... now with that said ........

IMPORTANT:
Now , there is one other thing , and going by your symptoms of it running at higher RPM (which would really kind of eliminate fuel pump) , would be the ECU/ECM , if it is bad , it likely could give crappy performance at lower RPM's and run at higher RPM's , unfortunately , they are not cheap , OEM is in the $400 range , and aftermarket can go as high as $1000 ..... You might try EBay , and look for a used one , you can get them fairly cheap there , and if it is the issue , it will be a much cheaper alternative than buying new ..... , and unfortunately , there is not really a way to positively test the ECU if the bike still runs at higher RPM , but lacks lower RPM power , there is no "test" for that

Thank you so much for the post! Today I bump started it, rode it for about two minutes, heavy throttle through all gears. Turned around, and when i hard accelerated it died. Quickly bump started, rode again for a few, and died at cruising speeds. I took the throttle body off and verified fuel is spraying when kicking bike over. Also verified spark when kicking over. Almost leaning towards ECU at this point. Verified spark and fuel. Bike will not kick start

Posted: **Mon Jun 15, 2020 6:40 pm**

Before throwing an ECU at it, try pulling the air filter and shooting some starter fluid down the intake. Not a lot, just a couple quick puffs. Then kick it. If it starts for a moment, you have a fuel delivery issue. Could still be an ECU (the injector is driven by the ECU in most vehicles), or you might have a bad sensor. You mention it runs when it's driven hard. Usually when accelerating the fuel maps are enriched for more power. That enrichment comes from holding the injector open slightly longer with each intake stroke. If there's a sensor giving the wrong info (TPS, Coolant Temp, MAP) it could be skewing the fuel maps and preventing low RPM use.

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