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Discussion Starter · #21 · (Edited)
Additional notes RE: Engine running rough 1000 to 4000 rpm
  • the engine is so rough under load at around 1500 to 2000 rpm that it's very easy to stall this bike from a green light.
  • It struggles and then catches it's breath at around 2000 rpm like a turbo kicked in. But it keeps coughing and popping like a gran'pa from 2000 to 4000rpm.
  • Also, I saw a black smoke flow out at cranking this one time. Never seen that before. I wonder if it is related.
Also Note to myself - order these parts to replace in the next few month:
  • Fuel Pressure Regulator
  • new battery
  • Spark plugs
  • Air filter
  • Resistor to bypass O2 sensor
 

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Discussion Starter · #22 · (Edited)
Update 9/20:

I really need your help..... I'm so tired of troubleshooting this bike.

When I pushed the start button today the bike made a loud "Crack" sound and failed to start. After the "CRACK" the bike fail to start with the start motor cranking only momentarily (maybe 1/10 sec) each time I pushed the start button.

The "crack" was pretty loud. It sounded like a hammer hitting concrete. The puzzling part is that the bike started right up after turning it off and then on. BTW, no FI light flashing error codes (I really need to find that maintenance plug and pull the error codes now) and battery at 12.8v (@ignition off)

Any one have any ideas about this symptom ??

I'm getting close to being done with this bike. With this along with the rough idle that I'm all the sudden seeing in the last few days, I'm sick of trouble shooting it at every turn and worrying about getting back home when I do take it out. I may just take the 2k$ that was offered as a trade in.
 

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Discussion Starter · #23 ·
Found this thread : Loud clunk when I hit the starter, then started up fine when I tried again

This is exactly the symptom I was having in the post immediately prior (i.e. loud crack and failed start) and it seems to blame FPR. And the FPR can be the cause of a low rpm roughness, which I am also having.

So, it seems that if I just replace the FPR, it'll resolve most of my issues ?? Do I see the light at the end of the tunnel ? I'm encouraged.
 

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I would buy a new battery, just riding a bit for an hour every few days isn't enough to keep it in top form and trouble shooting with a weak one will have you going round in circles.
I think the crack sound mite just be a mechanical noise because it hasn't got the juice in the battery to keep it spinning fast enough, I wouldn't worry to much about the crack noise.
Just get a new fully charged battery.
On rare occasions a bad RR not pushing out enough current and a bad battery can cause ruff low idle, like it wants to clear its throat, or on really odd occasion the bike won't rev past 6000 revs, and miss fire a lot popping and banging.
Also make sure the vacuum lines to the throttle bodys aren't cracked.
And make sure battery connections are clean and tight, and the starter solenoid wire connections are clean and tight.
And the main wire to the starter motor is snug, dont crank it down, it just has to be snug tight, not strangled tight lol.
 

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Discussion Starter · #25 ·
I would buy a new battery, just riding a bit for an hour every few days isn't enough to keep it in top form and trouble shooting with a weak one will have you going round in circles.
I think the crack sound mite just be a mechanical noise because it hasn't got the juice in the battery to keep it spinning fast enough, I wouldn't worry to much about the crack noise.
Just get a new fully charged battery.
On rare occasions a bad RR not pushing out enough current and a bad battery can cause ruff low idle, like it wants to clear its throat, or on really odd occasion the bike won't rev past 6000 revs, and miss fire a lot popping and banging.
Also make sure the vacuum lines to the throttle bodys aren't cracked.
And make sure battery connections are clean and tight, and the starter solenoid wire connections are clean and tight.
And the main wire to the starter motor is snug, dont crank it down, it just has to be snug tight, not strangled tight lol.
Thanks Bikerian,

I've ruled out the charging system being bad for the time being with the measured voltage generally being high enough. Having said that you mentioned few other things that were never mentioned specifically. So, I appreciate that.

I suspect I'll report back in few weeks, since I have to order parts and then install them. WIsh me luck.
 

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Give yourself a few days off first and try and forget about it, dont burn your head out with it, its usually something simple.
After a few days start from scratch.
Sometimes even a good battery can develop a bad cell, and it wont show until it's under high load, IE when it's called upon to start, then after its managed to actually start it, it has trouble recovering then it snow balls, one thing after another.
So step 1: a good known fully charged battery, I would just get a new one.
Step 2, make sure you have some good switch/contact cleaner and take your start switch gear apart and clean it.
Step 3, make sure battery and starter solenoid and starter motor wires are clean and tight.
Step 4, put your new fpr on and make sure all vacuum lines are good with no cracks.
1 other thing is has the loom fix been done? On the factory wiring block that are a known problem with age for corrosion?
Step 5, clean all connections with cleaner, every one and look for corrosion, but make sure your battery isn't connected until you have finished cleaning, and reconnecting loom plugs.
Step 6, change all your fuses for new good ones.
Step 7, put battery on make sure the connections are clean and tight, then fingers crossed press start button and report back.
Sorry to go on, but when you have burned your head out with problems, over looking the simple stuff is easy to do.
So it doesnt matter which way around you want to put it but, its.
1,spark.
2,fuel.
3,air,
And hopefully life!...
Keep us all posted👍
 

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Discussion Starter · #29 ·
Lol. Just for the record it does start. Just rough running at below 4000 rpm. If i cant fix it, i may try to get 3000$ first and then move the price lower. (Probably optimistic, but i can try) Its worth that much in parts and only has 3300 miles at this point
 

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Lol. Just for the record it does start. Just rough running at below 4000 rpm. If i cant fix it, i may try to get 3000$ first and then move the price lower. (Probably optimistic, but i can try) Its worth that much in parts and only has 3300 miles at this point
The motor is still brand new lol.
Yeah, sit back for a while, and start afresh.
New battery first, then my check list👍
Oh 1 more to the list is, when shes running spray some easy start or what ever you have that's flammable around the throttle bodys rubber manifold's to the block, just incase you have some splits or cracks in them, and if there is, your revs should shoot up with a spray around them, but be precise with the spray, try and keep it around the inlet rubbers, so you dont get a false reading.
I know you stated how low the mileage is, and sometimes with age and very little use throttle body manifold rubbers can crack and you end up with a stumbling engine, running lean because of the extra air being drawn in.
To be honest, with such low mileage it's got to be something and nothing, but its definitely something to do with age and very little use.
Keep us all updated👍
 
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