UPDATE Bike is in the shop for ... who knows how long

[Chinjab]

So I decided to take my new CT to the dealership service center here in town. After posting the video of the engine knocking, where some of you fellas suggested the valves were out of spec, I figured they could check the valves.

Here's the update:

1) Valves are in spec. Knocking persists.
2) They took a few days to get a new gasket, and removed the right hand side cover figuring it might be the clutch. Clutch is fine.

3) Now they think it might be a "tensioner inside the motor" and I have to give them the ok to "get in there and see"

So, now I'm just sitting here frustrated... do I let them crack the engine? Do I just live with a knocking noise that nobody can diagnose? At least I have my old CT90 to ride around in the mean time... but man this is annoying. I don't really trust dealerships, and loathe the idea of having them crack the casing. Maybe that's me being paranoid?

Never imagined this being the situation...

Any suggestions?

 

[m in sc]

to get tot he tensioner they only need to pull the LH case cover, not split the cases.

 

[squeaks]

Mine will give a knock,, or rap when it's cold first time in the morning if I rev the gas.
But then it's gone after a minute, I just assumed it was a cold piston slap .
Does it do it all the time?

 

[Chinjab]

It was more of a deeper knocking noise - I made a video here https://www.youtube.com/shorts/LSzuVsdoBBY

It would go away after I rode it a bit. But if I stopped, even for a few minutes it would be back. Any rpm increase and it disappeared.

I got a call from a tech at the shop just now to clarify... they don't need to 'crack the case' but just access the left side cover (as m in sc mentioned) and remove the flywheel. The girl who called me had 'miscommunicated' (sheesh).

He said the mechanic told him that the tensioner needs to be oiled specifically and that sometimes the oil can bleed out, and it doesn't get lubricated when starting... but apparently can be remedied.

At least they seem to be interested in the solution, so I'll see how it goes.

 

[m in sc]

thats true but usually wont bleed back down. the check valve int he plunger might be the culprit if it bleeds down again. .02

 

[squeaks]

The noise on your video is familiar to me. But I get that for just a second or two.
But I've got the older engine so could be a coincidence.

 

[AZ7000']

Does it still make the noise with the original dip stick?

 

[Daytripper]

Any suggestions?

If this were to happen to me where I would need to take mine to the dealer I would have to load it in my pickup, put it on the ferry (4.5 hours each way and close to $500) and take it to Juneau. Then when it is finally done I might have to come and collect it if I can't find someone to take it to the ferry. All the more reason for me to learn how to do the "Zen" thing and learn how to work on this bike myself. It is the same with my Honda Recon ATC, and I also have 2 Honda snowblowers. Have to do all my own maintenance or am dead in the water.

I think I would soon get the shop manual (I get shop manuals for everything and I plan to get one for the Trail soon myself) and at least when they say they want to try something you can look at the manual drawings, the procedure and have a bit more knowledge so that A, you have a better chance of knowing if you are being taken for a ride, and B, you may be able to diagnose and repair it yourself.
Then there are always the knowledge base here on this site too!
Best of luck, hope you get it sorted out.

 

[Chinjab]

Does it still make the noise with the original dip stick?

Dude. Don't say that. If it's because I put an aftermarket dip stick in there....

It could be. It could! I do think it happened after that...

Oh man...

 

[Low-gear]

Uggg, that might be an akward conversation with the dealer!

 

[Chinjab]

So... the mechanic concluded:

The clutch is working perfectly fine
Lubricated and adjusted the cam tensioner (but it seemed fine anyway)
I swapped out the aftermarket dipstick for stock
Checked all plastics and other rattly things
...

The dealer put it all together and said "well, call us if you want, but it still makes this noise and there's nothing wrong with it"

It still rattles when starting up.

On the way home from the dealer there were some incredibly loud and strange noises coming from the motor when shifting. When depressing the shift lever (or lifting it up) there was the usual 'click' and then upon the pedal release a LOUD "POP" noise started to happen, and got even louder. I made it home, intending to grab a quick lunch and then take it back to the dealer.

I got back on the bike, and the POP shift noise was gone. I rode around and around, and it never came back.

SO... here's my verdict.

The bike runs PERFECTLY.
It just makes strange NOISES.

I shall ignore the strange noises: a) until the bike dies b) until it explodes, or c) indefinitely

I figure I have 7 months before the warranty runs out. Let's see what happens.

On a good note, my bike finally has a name: The Rattler

 

[Daytripper]

Gawd I hate intermittent issues like that! Had a boat motor that used to mess with my head whenever I got too far from the dock. It would drop a cylinder, make me turn around and head back, at which point it would pick the cylinder back up and be fine. Took it to the mechanic and he could never get it to act up. Finally got a new Yamaha on it and problem solved. All it took was $9K!

Sometimes the issues of the mysterious kind work their way through and fixes themselves, but that is the exception. Like your idea of running it till its out of warranty, and then decide to get a new engine, or a new bike.. Hope it resolves itself!

 

[Chinjab]

Yep, how much could a new engine be? A couple or three grand? I've spent more on less in my past

 

[m in sc]

I wouldn't sweat it. i swear it had something to do w the auto clutch (the shifting clunk and such, and it sound like whatever it was settled back in, that whole spring/3ball actuator plate mechanism is super hokey. clever but..). as far as the motor being noisy.. noisy is subjective.. as compared to.... what? my XR150 is noisier than i feel it should be, sort of, the head and valves etc are all stock, at just over 2k on it in a year, its settled in and is fine. Not silent, but fine. thes emotor sare VERY hearty overall, especially in stock form. IF there is a defect, you have it on record that the dealer looked at it.

 

[Daytripper]

Yep, how much could a new engine be? A couple or three grand? I've spent more on less in my past

Well maybe not an new engine, but if whatever is going on intermitted will likely do one of 3 things, keep going on as it does now, fix itself, or fail, at which point they will know what it was and fix/replace parts. It is still running, and doesn't stop running intermittently so there is that.

 

[Cpd419]

My buddies 24 is in the shop for a knock low on the right side. Been there two weeks hasn’t been touched yet. Broke in easy, maybe 200 miles, and has done it since new.

 

[Chinjab]

My buddies 24 is in the shop for a knock low on the right side. Been there two weeks hasn’t been touched yet. Broke in easy, maybe 200 miles, and has done it since new.

Exactly my problem. I did a by-the-book break in, now has 1100k.

I'm almost certain it's the clutch. Although they inspected it and said it looks fine, it makes random very odd pops and knocks only when shifting. The knock actually is noticeable on the clutch side when you put your hand on the casing right where the clutch is.

My plan is to just ride it. And if it hasn't locked up, blown up, or resolved itself somehow, I'll take it in at month 11 of the year warranty and tell them I want the knock gone before they give it back.

I imagine Honda just has to put in a new clutch assembly, which really isn't that expensive, and is an easy job even for a novice like myself were I to do it.

In the mean time, I'm riding every day. The freakin' bike is amazing fun.

 

[AZ7000']

Grip it and rip it bro!!!

 

[PegLegRacer]

My ‘23 CT has developed a similar knock as you OP.
My fix was a Takegawa Oil Pump.
I attributed it to oil starvation somewhere.
The noise is gone very shortly after startup now.

 

[AZ7000']

My ‘23 CT has developed a similar knock as you OP.
My fix was a Takegawa Oil Pump.
I attributed it to oil starvation somewhere.
The noise is gone very shortly after startup now.

Cause and effect vs coincidence…. There is no way that 100’s of thousands of these and related Honda 125 motors need an aftermarket oil pump due to starvation of a stock motor.
I’m glad your sound is gone but I don’t think an aftermarket oil pump solved an actual issue….
My opinion anyway