Cam Chain Tensioner

[MrSinator]

Well, I'm taking an approximately 500 mile ride next week when I go for some work training. Just got done with some heavy riding this past weekend in Bristol race traffic while visiting my parents. It's run fine and seems to just be getting a little louder with the heat. I won't have the money or time for a trip to the dealership (where I can get a loaner bike if necessary) until mid-April. It's been running just fine so I'm going to assume that it's good for the next few weeks at least. This is the first fuel-injected Honda that I've had so maybe it's just a normal noise. I just got the bike in September '11, it had a little over 700 miles and had not had the break-in service done. Of course they run tight and quiet when they're brand new so I'm hoping that this is just the sound of things settling in. I'm going to have them listen to it when I go for the 8k mile valve check. I borrowed a stethescope from a neighbor that works on those little tuner cars but I couldn't isolate the noise. Could hear it everywhere I listened, all the way down to the crank case. Didn't seem to be louder or softer in any particular area. Plus I had just gotten home from work, temperature guage was at the halfway mark from all the stop-and-go traffic by the time I got to the apartment parking lot. My Boulevard had a similar noise but the mechanic at the Suzuki shop said that everyone complained about that noise, just really loud valves, sounded like you were riding an old Singer sewing machine. Soon as I get it checked out, I'll let you all know, just in case. Those pics of the DN-01 tensioner just got me paranoid.

 

[MrSinator]

So I got her back from the shop yesterday for the 8k valve adjustments. Front cylinder had 1 intake valve out .001 and the rear cylinder had 1 intake and 1 exhaust out .001. So nothing to worry about at all as far as the valves go. I asked them to kind of look at the cam chain the best that they could while they were in there without incurring any additional charges. They said that they could not find anything that looked out of place on it. My NT is also the highest mileage NT that that particular dealership has seen to date but said that they had been hearing from other shops that it has rather noisy cam chains in there. After leaving the dealership, I noticed that it's still making the same noise, just not as consistent or as loud so I'm starting to wonder if it may have more to do with the valves rather than the cam chain. I rolled straight over to my favorite shadetree mechanic (at the non-dealer service center) and had him listen to it again and told him about the valve adjustment and everything. He said that since I had been in there a few weeks ago with my bike, he has had 2 other NT owners come in and complain about the noise under the tank.

So at this point, I'm gonna chalk it up to just a noisy valve train. Still gonna pay some attention to it, just not as much. I had never heard that sound on a bike before and that's what had me worried about it. Oh and Bob, I'm one of those that revs the heck out of my engine as well, lol. I've had this bike for right at 8 months now and have put almost 9k miles on it and it appears to me that this bike loves the higher RPM range. I have to admit though, I'm anxious to sit on a new V-Strom when they arrive. May be saying goodbye to the NT soon depending on how the new DL's feel.

 

[Phil Tarman]

I get Dudley up to that 8500 rpm redline fairly often. I don't hit the cutoff very often. He's no louder than Tumbleweed and TumbleToo (my two '99 Connies) were. I've got 39,000 miles now and other than a faulty throttle position indicator (replaced under warranty) and the plug caps (replaced because my dealer thought if they might need replacing, he was going to replace them before might turned into must. I appreciated that.

If I were getting a Wee-Strom, I'd almost certainly spring for the Adventure model plus heated grips, centerstand, metal (non Suzuki) bash plate and end up spending almost as much as I spent on the NT.

 

[Chucksklrst]

How to make your bike quieter? EAR PLUGS. Also saves your hearing.

 

[Nicole]

I normally use ear buds and music to pass the time so I don't notice much wind noise

 

[dnktng]

I asked them to kind of look at the cam chain the best that they could while they were in there without incurring any additional charges. They said that they could not find anything that looked out of place on it.

Good to hear that it wasn't a cam chain tensioner issue.

 

[MrSinator]

Well, coming home from work today the PGM-FI light started flashing. 8 blinks, so I guess it's back to the dealership in the morning. The first sunny day all week and it'll be back in the shop, lol. Thinking more and more about trading this bike. I love the way it rides but if it's going to be a constant maintenance thing, I may go back to Suzuki.

 

[Phil Tarman]

Sure seems like you've had more than your share of trouble with your NT. I had the 8 blink thing (IIRC). I believe that shows a low voltage indication at the throttle position indicator. The first two or three times the light came on, I couldn't tell any change in the way the bike ran. I called my dealer and they said that there was a default FI program that might result in slightly lower gas mileage, and that they'd work me into the shop when I could get there. I was swamped with work and didn't get in for over a week, and then one day, the light was off.

I called them again and they said that if it came back on, they'd get me in, but if it didn't, they could check it the next time I was in for a regular service.

Then, I was in Denver for a doctor's appointment and was going to a friend's house. Just as I was merging into southbound rush-hour 4:00 traffic on I-25, the light came back on and the bike would just barely run. I managed to get off the freeway and stopped at a light and it began to run better. I called my dealer, Sun Honda, and they said that if wanted to chance it, they'd check it as soon as I got there. It was about 12 miles in rush hour traffic, but the bike ran sorta' mostly semi-OK as long as I didn't get it above 60 (and I couldn't get it above 60 if I tried). I pulled up at Sun, turned it off, then turned it back on and the light was out and it ran fine.

They ordered a TPI after checking the computer and seeing that low voltage indication and they ordered a new regulator/rectifier as well. Two days later, they had the parts, I rode back into Denver, they swapped out the parts and I haven't had any trouble of any kind since.

I wish you good luck! Keep us posted!

 

[elizilla]

Too bad you didn't make it down to Tellico Plains to meet me and John H, we'd have listened to your bike to see if it sounds like others. Did you get the PM I sent you last week?

 

[MrSinator]

I haven't been on the site much lately, been working quite a bit. Have a big audit coming up so I've been pulling overtime. I just read your PM's this afternoon. I'm hoping it's a simple fix. I've been dying to get a good ride in.

 

[MrSinator]

Got it to the shop today. There is apparently a an electrical issue. The intake air temperature sensor is constantly reading -40 degrees. They traced it down to the wiring. Apparently, the wires that plug in to the sensor are twisted up but they said that it didn't look as though they had been intentionally twisted. They aren't kinked or anything, they just go into the plug at the wrong angle. They took some pictures and are going to order the appropriate parts after they speak with Honda. It's all going to be covered by warranty. They said it would be fine to drive on right now, just have that annoying PGM-FI light on all the time. The computer automatically fail-safe's the temp sensor to 77 degrees, which the temperatures were above that all day here so no worries. Hopefully they'll get the parts in by next weekend so I can get this issue fixed. I also asked them about the cam chain and they said that they had several people come in with NT's and that they were all complaining about that noise. Their shop manager called Honda to report it and Honda said that they were aware of the noise. Their explanation was that the chain guides just get a little worn down during the break-in and that it's not really anything to worry about. They've been using that motor for a while and that's just one of the characteristics of it. So, I guess I just gotta live with the noise. Nice to finally get a decent answer about the cause of the noise. Now I just gotta get that PGM-FI light to turn off. That bright orange light in the middle of my dash is just an eyesore.

 

[Phil Tarman]

Well, I'm glad that you can ride the bike, and I'm glad that it's nothing major with the engine. Ear plugs for the cam chain noise might help.

 

[MrSinator]

The air temp sensor is at the front of the airbox. The sensor is a little white plug that is held to the airbox by a couple of screws and has a gray plug from the wiring harness that clips on to it. The wires coming out of that gray plug are twisted on mine. They are held in place with a greenish epoxy-looking stuff. I just hope I don't have to have the entire wiring harness replaced. Would have to leave it overnight and I have no way to get back to my apartment if I have to leave it there. Hopefully it will just involve getting a new plug and splicing it in or plugging it in to the main wiring harness.

 

[elizilla]

That's the plug I can never unplug, so when I have been in for the valve adjustments I end up just detaching the sensor from the airbox so I can remove the airbox.

 

[Coyote Chris]

Good and interesting thread. I too think the NT is a normally noisy bike. I ignore the noises. I get used to them until I ride my Connie and it doesnt make much noise. Then I go back to the NT and I notice them more but I ignore them.

This story probably is not applicable to this thread but it has an interesting lesson for those changing oil or changing their own oil and noticing changes in sound. My wife has this ancient Subaru with 298,000 miles on it. One day, a hydrolic tappet started to tick and went on for maybe 1,000 miles. There are 4 valves per cylinder. I talked with a dealership mechanic about this when we had my wife's newer subaru in for maintenance.
He said, did you change the oil and did you use a Subaru filter? I said I did change the oil but I used an aftermarket filter. He said, "Just to say you did, change the oil again and put on a Subaru filter." I did as he said and the noise went away in 2 miles.

 

[MrSinator]

Still no word from the dealership about how they're going to fix this. I have to go out of town for job training again next week, about a 3 hour trip there. They said the bike should be fine to ride. Feels a little sluggish when it gets hot. But if the computer is defaulting to 77 degrees and it's 90 degrees outside, I guess the mixture would be a little off.

 

[MrSinator]

Heard back from the dealership yesterday. Honda wants them to pull the entire wiring harness and send it to them, then they'll send me new one. I'm not waiting around for that. I explained to them that this is my main transportation, so Honda said that it was okay for the dealership to replace the sensor and try to repair the plug as best they can. If that doesn't work, then I guess I'll be riding with it as is until fall comes around. I'm not going to wait around for a weeks for them to replace the whole wiring harness. The problem is that there is no way to just replace the sensor plug without replacing the whole wiring harness so I guess we're going to try the simple fix of just splicing in some new wires. The mechanic said that he was pretty confident that the simple fix will work and that he's sure he can do it and it will solve the problem. Let's hope so.

 

[ARKNT]

Don't think I've heard of replacing the whole wiring harness in a case like yours, but with warranty that would get them a known fix.
I'm sure it could be spliced back into good shape. The mechanic just needs to be careful and seal it all up well to prevent later corrosion issues from cropping up.

Good luck,
Brad

 

[dnktng]

It's a 2 wire sensor. Seems that the plug could be replaced, and if the that leaves the wiring to short to get to the sensor, make 2 in, 6 in, 12 in, whatever it takes, 2 wire jumper set.

I try to think how I would fix this on my warranty expired NT. Id also try longer jumpers back to the ECM from the sensor. Run it for a couple of weeks and if that fixed it, then I'd start looking at a wiring harness replacement. Or possibly leave a jumper in and make it waterproof, permanent. Pulling a wire harness because a bad sensor plug, WOW, that is overkill. I'm a little surprised Honda is willing to do a wiring harness replacement before trying other options, at least to verify it's the harness and not the sensor connections at the ECM or that jumpers couldn't safely extend your current wiring.

Also I wonder if this IAT sensor failure wouldn't cause some extra engine noise if it is potentially causing an incorrect (or at least not perfect) amount of air to enter the engine, not the best combustion, throttle body open possibly too much for correct air temp, .....just worndering. Nice to hear yours side by side another NT, now and when this is finally resolved.

Good luck. Very intersting thread.

 

[MrSinator]

Took it to the shop today and got it fixed. They had a wiring harness off of another sport bike that had the same style plug. Cut mine out, soldered and shrink wrapped the new one in and it worked like a charm. They went ahead and put a new sensor in too, just in case. She's running a lot smoother and a lot cooler now. Feels great. I hope this is the end of that ordeal.