Jump to content

Clutch question


durk
 Share

Recommended Posts

Today I took my bike out for a ride and ran into some issues when I would approach 9-12k rpms. I'm pretty sure it's the clutch slipping. I experimented multiple times on the way home. I basically started around 6k rpms and rolled the throttle on pretty hard in 1st, 2nd, & 3rd. All acted the same. I focused on the tach and it seemed to pull consistent all the way up to 12k but I could feel the bike loose power then kick back in. This usually happened somewhere between 9-10k rpms. It seemed like I noticed it earlier in the day as well as I went to make a pass uphill, bike kind of lost power then felt like it hit a power band and took off. I was not focused on the tach at that point, so I'm not sure what was going on there. Does this sound like the clutch is slipping to you? If that's the case what all would you replace? Just fiber disks? Whole pack? Springs? Would you go aftermarket or OEM? If aftermarket what brand would you use? Last ?  The bike has a hydraulic clutch, is there much difference in replacing the clutch as compared to a cable one? The bike is 2006 cbr1000rr with 38,500 miles and has not always been ridden gentle since I took ownership of it. 

Link to comment
Share on other sites

Sounds more like an engine issue to me, fuel starving...ecu messing up..plug wires. Something like that. When a clutch slips its really obvious m

The best way to check the clutch is go grab 5th gear at 35 mph or so and go WOT. If the clutch is slipping it will slip like a mofo under those circumstances. The tach will climb and you wont go anywhere.

Link to comment
Share on other sites

20 minutes ago, Tonik said:

Sounds more like an engine issue to me, fuel starving...ecu messing up..plug wires. Something like that. When a clutch slips its really obvious m

The best way to check the clutch is go grab 5th gear at 35 mph or so and go WOT. If the clutch is slipping it will slip like a mofo under those circumstances. The tach will climb and you wont go anywhere.

I tried something like this and it did not slip. I remember you mentioning something about being in a high gear and getting the clutch to slip. I even tried pulling the clutch in at a slow speed and dumping the clutch at a higher rpm in 5th or 6th , and bike just bogged. 

You may be onto something with fueling. I did not mention the fact that the fuel pump lately seems to be louder at initial prime. I thought maybe this could be my issue as well. Do you think a fuel pump on its way out could cause this issue? 

 

Link to comment
Share on other sites

2 hours ago, durk said:

Today I took my bike out for a ride and ran into some issues when I would approach 9-12k rpms. I'm pretty sure it's the clutch slipping. I experimented multiple times on the way home. I basically started around 6k rpms and rolled the throttle on pretty hard in 1st, 2nd, & 3rd. All acted the same. I focused on the tach and it seemed to pull consistent all the way up to 12k but I could feel the bike loose power then kick back in. This usually happened somewhere between 9-10k rpms. It seemed like I noticed it earlier in the day as well as I went to make a pass uphill, bike kind of lost power then felt like it hit a power band and took off. I was not focused on the tach at that point, so I'm not sure what was going on there. Does this sound like the clutch is slipping to you? If that's the case what all would you replace? Just fiber disks? Whole pack? Springs? Would you go aftermarket or OEM? If aftermarket what brand would you use? Last ?  The bike has a hydraulic clutch, is there much difference in replacing the clutch as compared to a cable one? The bike is 2006 cbr1000rr with 38,500 miles and has not always been ridden gentle since I took ownership of it. 

Easy check to verify if it's clutch, when you feel it "loose power" do the RPMs increase quickly?

Link to comment
Share on other sites

8 hours ago, whaler said:

Easy check to verify if it's clutch, when you feel it "loose power" do the RPMs increase quickly?

Rpms never really jumped, just seemed to continually increase without stumbling. It was difficult to stay locked in on the tach because even in 1st gear at 9-10k you're moving pretty fast.

I'm really leaning towards the fuel pump now. I usually ride with earbuds in and I typically turn the music on before firing the bike. A couple weeks ago I was just moving the bike around at the house and turned the key and the pump sounded much louder. Sounded like it was struggling enough to make me look for a pump on EBay. I even told my wife that I thought my pump was dying. Bike was running fine, however, as rode back and forth to work. I was riding more aggressive yesterday and I noticed it acting funky shortly before I stopped to get fuel but I just thought I must have been in too high of a gear. After fueling up and using the restroom I hit the road and started to focus in on the issue. At first it seemed fine, but then shortly after it started to have the same issues. I'm probably going to go ahead and order a pump off EBay. I don't think cleaning mine is going to fix it by the sound that is making. 

  • Upvote 1
Link to comment
Share on other sites

It certainly wouldn't be out of the question for an 11-12 year old sport bike with 40K hard miles to be in need of a new clutch.  As others have noted above, if feels slow to accelerate but the RPMs are rising quickly, go clutch.  If the bike feels slow to accelerate with throttle and the RPMs hold stable, you've got another issue--fuel/spark/???

  • Upvote 1
Link to comment
Share on other sites

Of course when I just took the bike out for a quick 10 min ride I cannot make it repeat it's  hiccup. Chalking it up to the bike needs to run longer before it shows it's ugly head. We'll see what it does tomorrow on my 30 minute commute to work. I know it did not magically fix itself. I hate chasing problems like this. 

Link to comment
Share on other sites

2 hours ago, Isaac's Papa said:

Fuel pump needs to get hot before it starts to fail, possibly. If that's the issue, that is. 

 

That's what I was guessing. Thanks for the input.

I'm curious to see if it will act up after my commute. I went ahead and ordered a new-used pump for it. I would like to be able to test to see if it cures the issue before I head out on an all day ride. Yesterday was a 5.5 hr ride and I noticed the issue around hour 3. So my commute may not do it. Worth a shot though. 

Edited by durk
Link to comment
Share on other sites

1 hour ago, Isaac's Papa said:

Does it act up with a full tank, or as it empties? The fuel will act as a coolant for the pump. 

It did not seem to matter. I first noticed it at less than half a tank as I made some hard passes on a couple of cars. I thought maybe I was in the wrong gear and I would pay more attention. Didn't really get on it after that as I made my way to a gas station where I was nearing empty. Left the gas station and started to experiment. At first everything seemed fine and I thought, you're worrying about nothing. Then I kept experimenting and shortly after it showed it's ugly head again. Doubt I was below 3/4 tank. I'm thinking the 10-15 min break at the gas station from fueling up and using the restroom did the pump some good. If it is in fact the pump, the break plus the fresh fuel possibly having a cooling effect. Once it started to act up I could recreate the symptom each and every time I cranked on it. 

Link to comment
Share on other sites

5 hours ago, Isaac's Papa said:

Doesn't sound like the pump to me. It's rare that they act up intermittently. I think it's either clutch (which I still doubt based on your comments) or spark dropping. 

How old is the battery? 

The only reason I'm leaning towards the pump is that initial prime sounds as if it's struggling. It sounds as if it's hesitating and seems loud to me. It's not a nice consistent prime up sound that I'm used to hearing  on a FI motor. 

Just recently replaced battery. As in less than month old. 

 

Link to comment
Share on other sites

1 hour ago, CrazySkullCrusher said:

I'm assuming efi bike? Check resistance at tps? Check maf sensor? Check air filter? Check to see if injectors need cleaned? 

Yes efi. Air Filters were replaced less than 7,000 miles ago as well as cleaned the injectors. Will possibly look into checking tps and maf. I'm hoping to be able to figure out a way to recreate the problem so after I try to fix the issue I can know it's gone without having to ride for 3 hours plus. It of course ran like a champ the whole ride to work. 

Link to comment
Share on other sites

Nothing that I know of. I bought the bike used. I tore into this year to check the valves and as I worked my way through to get to valves I did not notice anything.

 

Some additional info:

Yesterday I stopped at the local shop and had the owner listen to the fuel pump prime up. He agreed that it definitely does not sound right. Then I tried to have another guy there listen to it and it sounded fine no matter how many times I cycled it. Even if a started it for a second it sounded fine. So when I got home (just a short ride) I cycled it after I shut it off and it stuttered the whole way through the cycle. It was the worse I have ever heard it. Then I cycled it again and it sounded about  smooth as could be. So my thoughts are its struggling on the initial prime after being ridden due to the fact it has to work harder. The second cycle does not have to work much since it's just cycling fuel through the rail and not really having to pressurize much. I'm thinking though if it sounds that rough on initial prime it probably is struggling at some point while running as well. It makes sense to me that the longer it runs and the higher the RPMs the more it will struggle. I'm no expert by any means, however, and I appreciate everyone's ideas. Thanks again for your input.

I may be wasting money on a pump as it may not be my problem, but I know it does not sound right. I wish I could have recorded it yesterday. My brain as a math teacher can't put into words what it sounded like. After I heard it, all that came to mind was the sound of rapid firing on the old Space Invaders video game. 

 

Yes it kind of had that high pitch sound. Not quite as loud, but it seemed to squeal a bit like a pig. 

Link to comment
Share on other sites

1 minute ago, hiro said:

Another dumb thought: Could it be related to poor tank ventilation? Or was that covered already?

Not sure. I don't suspect it would be, because the only thing I have done recently is replace the battery and that does not require pulling the tank or anything near it. Therefore, I don't see a ventilation hose being pinched or anything of that nature. I feel it could be just about anything. To me the bike is no spring chicken. It's 11yrs old with close to 40,000 miles. Maybe the guy looking for a 1000cc bike will buy it. 

Link to comment
Share on other sites

Just now, durk said:

Not sure. I don't suspect it would be, because the only thing I have done recently is replace the battery and that does not require pulling the tank or anything near it. Therefore, I don't see a ventilation hose being pinched or anything of that nature. I feel it could be just about anything. To me the bike is no spring chicken. It's 11yrs old with close to 40,000 miles. Maybe the guy looking for a 1000cc bike will buy it. 

Sometimes the pressure/vacuum relief in the fuel cap gets clogged and will not allow the tank to equalize.

Might be something to checkout... when it starts to stutter, stop and open your fuel cap. Do you here an inrush of air? That would be vacuum lock. A full tank would make this show up quicker than a low level.

Just one more thing to check off.

Link to comment
Share on other sites

I'm imagining it like this: When the bike is cold there is some vacuum in the tank. The sound of the fuel pump is showing that. The bikes warms up and the fuel expands and relieves some of the vacuum. But then, after pulling fuel for a while, it starts to create the vacuum again. That might cause reduced fueling...but, that might not be consistent with the power suddenly kicking back in. A mystery. heh Probably something simple. Maybe it is the pump.

Edited by hiro
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...