Knocking and rattling inside the variator and clutch housing

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neb4152
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Knocking and rattling inside the variator and clutch housing

Post by neb4152 »

Got to work this morning and the noise was worrisome. Knocking, rattling, like something has come loose. Didn't have the noise when I left for work. About a 10 min drive. Had a new ncy kit in there for a couple months. Haven't had it open in about a month when I changed the gasket. Been running fine until this morning. Will it get me home to work on it? Any ideas. Will open it up tonight either here at work or at home.
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Re: Knocking and rattling inside the variator and clutch hou

Post by Mel46 »

I wonder if one of the rollers came loose, though I don't know how it would. The rollers are tucked in the variator fairly secure, two at a time.
I do know that if the nut that holds the assembly came off it would stop running all together. Dave and I had that problem once, and the bike just stopped going forward.
Is the knocking only when you start off, like the clutch slipping? Glazed clutch pad?
How old is the belt? If it is old enough it could start shredding. I'm running out of ideas.

If it is only a 10 minute ride, how much is at high speed?
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NCY variator, drive face, and rollers
neb4152
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

I don't know if it will still go. Knocking is when idling and and at 5-10mph speed, although thats the only time I noticed it. I didn't hear it till I pulled in to work, stopped, shut it off, and restarted. Hasn't run since. I'm thinking belt, or one of the big nuts is loose. Maybe the clutch. Won't know until I open it up. Maybe a roller but I don't know how that could happen either. Acceleration was good and consistent Maybe 5 min at 40 to 50mph. Belt has maybe 500-750 miles on it. Replaced when I got the ncy kit. Will update what I find.
neb4152
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

It's not the variator or clutch or pulley. Ran it with everything off. No variator, belt, clutch, etc. Still had the noise. Something in the engine. When I Rev it seems to go away or less noticeable. Could this have been caused by the new exhaust I put on 10 days ago? See the vids. One of the sound with engine off and one with it on.
https://youtu.be/WtL2kj23LDA
https://youtu.be/Hr_LYQNkfLI
neb4152
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

drove the 10 min home. seemed normal other than the noise. At speeds above 15-20mph, the noise is inaudible but I heard it in the exhaust this time and also had some backfires. Backfires to be more common since the new exhaust. I'll put the OE exhaust back on later and change the oil. Figure if there is engine issues it will show in the oil. If that doesn't fix it I'll send it to my local honda dealer. It's over my skill level I'm afraid.

viewtopic.php?f=9&t=8897

Link about my 10 day old exhaust.
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

Just added about 4oz of oil. No idea. Checked a couple months ago. Just hope I didn't go too long like that. No sign of leaks or burning oil. Gonna start fresh tomorrow.
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Re: Knocking and rattling inside the variator and clutch hou

Post by PCX150Rider »

Backfires are usually caused by an air leak or exhaust valve hanging open too long.

Seems to be above my skill level as well. You tightened the flange bolts and gasket enough on the new exhaust right? Is it one of those kind of exhausts that has an inner and outer pipe? Sometimes welds break on exhaust systems internally and they rattle. My old Honda Rebel 250 eventually had rattling exhaust pipes. :|
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Re: Knocking and rattling inside the variator and clutch hou

Post by you you »

What else have you modified on the bike?
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

you you wrote:What else have you modified on the bike?
Variator and clutch, accessory lights, and the exhaust. That's all.

I've determined from other scooter forums (not hondapcx) and from YouTube vids describing a very similar sound in scooters that this may be the crankcase bearing. Not easy to get to.
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Re: Knocking and rattling inside the variator and clutch hou

Post by you you »

neb4152 wrote:
you you wrote:What else have you modified on the bike?
Variator and clutch, accessory lights, and the exhaust. That's all.

I've determined from other scooter forums (not hondapcx) and from YouTube vids describing a very similar sound in scooters that this may be the crankcase bearing. Not easy to get to.

I think I'd definitely pop the original exhaust on and see what happens..
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Re: Knocking and rattling inside the variator and clutch hou

Post by Mel46 »

+1
If you still get the rattling after you replace the exhaust with the original one make sure your valves are adjusted correctly too.

Was the engine 4 oz low on oil? That isn't much but on a little engine that does not use much it is worth the effort to make sure it isn't leaking.
Currently own:
Red 2013 Honda PCX150

Givi tall windshield & tailbox - Lots of extra lights
Custom seat from Thailand - Bad Boy Airhorn
Takegawa Lowering Shocks - Michelin City Grip Tires
Headlight assy upgraded to LEDs w/HS5 main bulbs
NCY variator, drive face, and rollers
neb4152
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Re: Knocking and rattling inside the variator and clutch hou

Post by neb4152 »

Mel46 wrote:+1
If you still get the rattling after you replace the exhaust with the original one make sure your valves are adjusted correctly too.

Was the engine 4 oz low on oil? That isn't much but on a little engine that does not use much it is worth the effort to make sure it isn't leaking.
4oz is all i had. stick was bone dry until then. may have been able to add more. i checked the oil and the valves a couple months ago. the more i think about it the more i worry i went without oil in the right places. working on getting it transported. It will still run and go but Im not taking any chances.
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Re: Knocking and rattling inside the variator and clutch hou

Post by springer1 »

Was the level shown on the dip stick correct after you added the 4 oz ?
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