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Discussion Starter #1
Alright soooo I've got another new problem. I am guessing I may know what it is but looking for any advice/pointers etc.

3 instances so far of this happening and are as follows:

1. I blipped the throttle and downshifted 1 gear at a time from 6 to 4. Bike stalled rolling along on a straight. Took me by surprise so I didn't really understand what was going on.

2. I had to brake hard and downshift from 6 to 3. Had the brake on fairly solid and steady. Clutch was pulled in. Bike stalled out... :(

3. Happened this morning before I took off. Sitting in my driveway. I started the bike with the choke out. Let the oil cycle for a few minutes then pushed the choke in when it was warm. Before leaving I blipped the throttle a slight bit from idle. It sounded like shit. I tried it once again... It stalled. I started it right back up. Tried blipping again and it sounded terrible but didn't stall so I left for work.

I think a couple of things. I put on the pair covers and took the entire system off the bike and did the flapper mod. I also put new plugs in but I'm thinking I need my PC remapped.

My questions, if the valves need adjustment would it cause this?

:nerd:
 

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valves usually create more of a noise than a problem like that, but if they are WAY too tight, it could cause it. what is your idle at? I've seen bikes that for some unknown reason had the idle adjusted too low, which caused a world of annoying driveability issues such as this.
 

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1. Make 100% sure your engine idle is set properly. If the engine idle is too low at normal operating temp then stalling will happen when you upset the the airflow into the airbox.

2. Stop blipping the throttle from idle.

3. Stop blipping the throttle between each downshift while street riding. Completely Unnecessary
 

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Discussion Starter #4
1. Make 100% sure your engine idle is set properly. If the engine idle is too low at normal operating temp then stalling will happen when you upset the the airflow into the airbox.

2. Stop blipping the throttle from idle.

3. Stop blipping the throttle between each downshift while street riding. Completely Unnecessary

Thanks, Agreed, I never blipped the throttle while riding since I bought it, then everyone told me I should be when down shifting so I started doing it. Seems unnecessary but I went along with it. As for at idle what should optimum idle rpm be at/between? I never blip at idle, but did today where it stalled out to see if I could replicate the issue and to my surprise I did.
 

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Discussion Starter #5
Idle is about 1100-1200rpm
 

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Too low. Should be 1300 RPM.

Too low an idle can cause the charging system output to be too low to charge the battery.
All it would take is to be stuck in a traffic jam with the fans running to drop the battery charge level down to the point where the ECU stops working.

Happened to be with my VFR800. The difference was 100 RPM (1200 vs. 1300).
 

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Discussion Starter #7
So to get it idling a bit higher (easy/quick fix) pull the choke out a tiny bit?

The right way is to get the idle adjusted. Is it difficult to do on your own? I am going to get it Dyno'd and remapped when I get my new pipes on it but that wont be until next year.
 

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No, The Choke (air-bypass) should only be used for starting the bike and for a bare minimum of time. 5-10 seconds max

Let the engine get up to at least 180° and no more than 190° and immediately adjust the idle to 1300-1400 rpm. Do not wait until the engine temp is over 200° or you will be in a different A/F ratio window and the setting will be wrong when the engine temp drops back to 180ish

If you set the engine idle properly at 180° then by the time you hit 200° or more it will usually be idling around 1500rpm
 

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Have you checked your fuel pressure regulator?
It will cause stalling like you're experiencing if it's diaphragm is failing. It's a common Honda problem. Lots of threads here discussing FPR testing and replacement.

The Idle adjuster knob is on the opposite side as the choke.

My 4 years of limited experience with the RC51 has shown me that LDH and SubSailor are spot on with their description about adjusting the idle. When I'm at about 180F degrees, I'm right at 1300 rpm. When the bike is closer to 200 -220, the idle is a tad higher. around 1400 - 1500.
 

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Is this correct?
My bike idles around 1100-1200
Around 90 degrees

But i read this from LDH

No, The Choke (air-bypass) should only be used for starting the bike and for a bare minimum of time. 5-10 seconds max

Let the engine get up to at least 180° and no more than 190° and immediately adjust the idle to 1300-1400 rpm. Do not wait until the engine temp is over 200° or you will be in a different A/F ratio window and the setting will be wrong when the engine temp drops back to 180ish

If you set the engine idle properly at 180° then by the time you hit 200° or more it will usually be idling around 1500rpm
 

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this is interesting.

i just recently blocked off my pair covers, removed all the crap and removed all my flapper stuff as well. i've had the flapper disabled for the last 8 years on my SP1 and suddenly im experiencing the same thing. the bike died on me for the first time ever after a minimal blip at a stoplight (sometimes i blip sometimes i don't). never while rev-matching a downshift no matter how aggressive or lazily i do it though, and no, i wont be stopping that :p

i noticed after doing the pair mod my idle seemed a little lower than pre pair mod.
 

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It's been pretty clearly described. Your idle should be set at 1300 when at 180F degrees.
If your experiencing stalling problems, start by making sure idle is set right. Once that's correct, the problem is elsewhere. Like a bad fpr, or tps connector, etc..
 

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1300?!
Mmh my idle was around 1150-1200
And having battery problems
Now its around 1300.
And as for blipping well its a habbit to do that,,
 
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