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Discussion Starter · #1 ·
Hey guys, first time poster and mechanical noob here - as per usual I suppose.

I have an 88 MC19 with supposedly 21000km on the odometer.

The other day, as I was pulling into my father's street, I felt the bike lose power as I was riding up a slight hill. As I was pulling into his driveway, the bike died completely. It would start again with the choke on but would die as soon as I tried to disengage the choke. For reference the bike idles at about 4000RPM with the choke out (too high I know).

When I went to start the bike a few hours later, after enjoying a nice chicken parmy and a beer, the bike wouldn't start at all.

I went back a few days later and then the bike started an ran for about five mins, although it sounded somewhat sputtery, before it died.

I guess my question is, what's the best trouble shooting process to go through? My uneducated guess is fuel filter, fuel pump then carbs but I'm not really sure how to assess the condition of any of these things.

Thank you guys in advance so much. If I keep my mechanic out of this one then that would be great.
 

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Honda: INNOVA125i(2010); CBR250R(2013)
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Hi. The troubleshooting scheme is not specific to a particular model and is common to all motorcycles... almost... for example: Our motorcycle has no carburetor, yours has four carburetors.
Just please if you have no prior experience in mechanics, if you don't have the necessary time etc', please go to the nearest mechanic in your area. This is the fastest and safest way to treat your problem.
And let's start with the simple things:
  1. Check that the oil level is correct
  2. Check if there is fuel in the tank, move the fuel petcock to reserve position.
  3. If there is no fuel in the tank...You already know what to do.
  4. At this point your battery is probably drained. Check the voltage on the battery terminals, there should be a voltage of at least 12.7 volts. If not, recharge it and check again. If the battery cannot be charged, it means it is dead
  5. Then perform a battery voltage test during startup: There should be at least 10 volts. A voltage lower than 9 volts means that the battery is dead.
  6. If you manage to start the engine, go back and check the voltage on the battery terminals: It should be 13.9V at idle rpm. If you get less, it means that the generator (coils) is dead.
  7. Continue the same test with the engine run. At 5000 rpm the voltage at the battery terminals should be no higher than 15.5 volts. If it is higher, it's means that the regulator rectifier is dead.
  8. If the engine is running, does it make mechanical clicks or other unusual metallic noises?
Then come back and tell us what you found???
 

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I think you're on the right track that its fuel related. Change the fuel filter (if its accessible) and/or clean the carb jets with spray cleaner to start with. If you can get it going for any length of time, run a good fuel system cleaner like Chevron's Techron Plus through it. Hopefully it's just gummed up and it's not the fuel pump.
 

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I own a '75 Honda CB500T, so I know a thing or two about carburated bikes. The first question is, how long has it been since you last ridden your bike? Carbs are just notorious for gumming up with fuel. In my case, I would not ride the bike for few months at a time, so it is almost guaranteed that I have to get the carbs out and do an overall rebuild of the carbs each time I want to ride the bike again.
 

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Discussion Starter · #5 ·
I own a '75 Honda CB500T, so I know a thing or two about carburated bikes. The first question is, how long has it been since you last ridden your bike? Carbs are just notorious for gumming up with fuel. In my case, I would not ride the bike for few months at a time, so it is almost guaranteed that I have to get the carbs out and do an overall rebuild of the carbs each time I want to ride the bike again.
Thanks so much for your reply.

I had put about 500kms on the bike over a two week period before it died.

It was starting up quickly and easily each time, but it did have issues with rev hunting where at idle it would fluctuate +/-1000rpm so I had to set the idle adjustment screw to about 4000rpm when warm (its supposed to be about 1500).

I suspect this is part of the issue, do you know if rev hunting is strictly a mixture issue or could it be a dodgy fuel pump/dirty filter?
 

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I'm guessing you had to adjust your revs up because your revs were fluctuating too much and causing your engine to stall. Maybe you have issues with your float valves.

If your revs is constantly high, I would again suspect issues with your float valves as well as possible air leak somewhere.
 
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