I don't think she's running on all cylinders

So I went to MotoGP in Indianapolis a couple weeks ago. It's about 800 miles down there from where I live in Minnesota. I had a blast!
Anyway, on the way back my bike started acting weird. It lost serious power and was surging back and forth, as if it were running on 3 cylinders, then back up to four.

I could hold the throttle still, and it would just jump around. Higher RPMS seemed to clean it up a little.

Then for like 5 minutes at a time it felt like I had dropped down to 2 cylinders. I had barely any power! I couldn't speed up. I could barely maintain my speed. I rode the whole way home like this. It was awful.

Before the trip I changed my oil and put new tires on.

It's a 2002 Vfr800. Red . If you guys have any idea, help is appreciated greatly. It sounds like an ignition, coilpack problem. What do you guys think?

Also, my gas mileage was TERRIBLE after this happened.

 

I was down at Indy too....maybe I saw your bike, hehe. I was on a 2000 Yellow and as far as I saw, I didn't see another one, lol.

That would absolutely suck and to be honest, the first thing I would check is battery voltage and the state of the RR and stator to be safe. Low voltages can cause all sorts of issues. I would also check the connections/grounds associated with the charging system. It seems you were definitely having a spark issue and I wouldn't rule out a bad coil or ground either but coils typically don't go bad.....they can of course. Check things out and get back to us...

Oh...and was the wiring harness recall done?

 

How many miles on her? Not sure on the 6th gen, but on the 5th gen the spark plug change is 8k. I went 10k on a set no problem, this last set I was at 12k and she started running on 3 cylinders then back to 4, and was low on power. I pulled the plugs and while they all looked good, at least one was bad because a new set had her back running right :smile:

FYI: O'Reilley Auto sells the NGK plugs for almost half the dealer price :wink:

 

She's got around 15,000 on her after the trip! I have the wire harness recall done along with the VFRness being installed. Ok! When I get back home one of these weekends I will take her apart and check the voltages and plugs!

Any other ideas?

 

I'm finally home from school, and I'm wondering where to start looking for the problem.

I think I'm going to check the spark plugs first, and then go from there.
Does that sound like a good plan?

 

My experiences exactly, I get about 10000km from a set of plugs before the bike starts missing and drinking fuel.

 

Start with the basics - for an engine to run you need fuel, air and ignition arriving at the right time. As its running on a few cylinders then most of those things are OK on at least some of the cylinders, so focus on things which can affect a single cylinder/bank. plugs, leads, coil packs. Pull one at a time clean inspect reinstate. If anything looks wrong chances are you have found the blighter.

Keep the updates coming





SkiMad

 

Alright guys!
Thanks skimad. When I come home from school again in a week or so I'm gonna check the plugs, coilpacks, and leads. I might pick up a pair of plugs to put in her right away.

I didn't have time this weekend because my car got all the attention.

I'll update soon!

 

Sorry for reviving an old thread but mine has started doing this too, gonna try spark plugs when I can. ike has a full & regular service history but does not state what was done on each service

 

This is a classic electrical issue. Check every connector and frame connection. These coil packs use the bolt for the frame/spark return. Make sure that is clean and tight (not too tight, dont want to break it off). Next I would look at injectors as they can just act up. A flooded cylinder will act the same as one not getting any fuel.

I dont think its a charging issue or you wouldnt have made it home. The 6th gen can kill its batter fairly fast (learned this the hard way. Took my r/r off to redo the thermal paste, didnt connect it properly and took off on the bike. I went all of 80km and it was dead.) But low voltage to the ecu, coils, map sensor, o2 (even if you have resistors in place) can make it act up and do weird things.

Let us know what you find, help others by posting

 

Will do Zen, thanks man, thought I had it sorted, battery is still charging ok so hopefully it's not something more serious.

Just 2 questions:

1. Should there be dielectrical grease on the frame returns?

2. Battery doesnt seem to have any dielectrical grease on it but connection looks clean. Is this ok?

 

What aboot batter bolt torque? I happen to have a low torque wrench, the torque for battery bolts are 40 inch pounds, believe it or not. I used to think I had a good calibrated elbow, but when your dealing with lead and brass/stainless bolts, its pretty neat to have the torque right on the bullseye. Cheers

 

I have never had to torque a batt lead to the battery as the old saying of half turn passed snug has always worked. It works out to about 10ft-lbs which is plenty.

All your connectors should have dielectric grease in them. Frames connections are different. There is nothing to keep the grease there. Clean them real good then put them back together. You can either spray them with clear lacquer (check spelling on that one, phone is trying to correct it) or use some battery terminal goop. I use the spray and havent had an issue.
Your battery terminals are a bit different. They are tinned to be compatible to the other connector so they only oxidize on the outside. If your worried then get some battery terminal goop and brush it on. But I havent done that and my battery posts and leads are doing great. Then again I don't live by the ocean so take in account for salt water in the air.

 

Ok, I'll throw another spanner into the works, when I start the bike in the morning, no problem, starts up, fires on all cylinders etc

But the last 2 trips from work to home she's been misfiring. It should be said that it has been colder when I start work than it is when I leave but if it is electrical (I suspect it is given it's intermittancey) then temp should make a difference?

Please correct me if I'm wrong of course. I do know however that there is less resistance at colder temps than there is warm temps, so that might explain something....

I'll be taking a look at her tomorrow either way but please chime in if you can and hopefully make the process shorter

 

Follow Zen's advice. Difference in temp is minor in regards to conductivity.

When I put too high of wattage lights in an ran down my battery, it started to miss and run rich. Don't know if was ECM or Power Commander, but exhaust pipe was all sooted up!

Check you stator connector and clean with this easy tip:


Take a common emery board, trim to 1/4" wide, peel off coarse side (won't get it in or out), burnish each side of connector.

Corrosion can cause heat and loss of current, not voltage to charging circuit. Here is the analogy, whether the wires from the stator were 28 gauge or 14 gauge (stock), which would carry more current? They would both read 14.5 volts with a meter, only one would charge the battery.

Note slight discoloration in center connector, mine was starting! I eliminated these when I upgraded R/R.

 

I did change a headlight a while back when it went, but this only started a few nights ago. (Wednesday evening)

Forgive my probable ignorance, but what is emery board?

 

An emery board is a little cardboard sanding board for fingernails, you can find them in any cosmetic department

 

Cheers man! I'm assuming that the question you asked the post before last the answer is 14 gauge?

 

Yes, as odd as it may sound the lower the gauge number, the larger the diameter of the wire! Houses are wired with #12 primarily, and #14 for light circuits.

#28 would be like the wire for your headphones! It is so small, it doesn't have an ampere rating (current).

http://www.engineeringtoolbox.com/wire-gauges-d_419.html

This will give you an idea what we are talking about. From the table you can see #14 is rated for 24 amps, which decreases with temperature and number of conductors in a conduit, all very involved.