Clutch Hub Bearings and Noise

GoldenMotor.com

supercub

New Member
Nov 1, 2012
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New London, CT
I found this post in the forum and pasted the picture. It shows how the clutch hub/gearwheel is supported by ball bearings. I think that this is the source of alot of engine noise on my bike. Does anyone know how to open this up? I would check for broken balls and lack of grease. I did add grease to the clutch perch hole and that cavity is full but I don't think that the grease can get ot those bearings.
 

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crassius

Well-Known Member
Sep 30, 2012
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I occasionally press one of these apart to see what went wrong, but have only reassembled one just to see how well in would work. Way too much work involved when compared to the price of a new one.

Those balls are nasty. They look like all the out-of-round rejects from other bearings and are usually missing a few.
 

supercub

New Member
Nov 1, 2012
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New London, CT
It looks like removing the star nut and the nut below the clutch plate would be all to remove it? Does the shaft have to come out or is there anything pessed in to pull?
 

crassius

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Sep 30, 2012
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you need a puller to get the unit off the tapered shaft - after that, you'll still need to press the hub out of the basket

the bearing only works while the clutch lever is pulled, so if the noise is there while riding, it probably is coming from something else
 

supercub

New Member
Nov 1, 2012
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New London, CT
It makes noise at higher speeds and quiets down when it is under load up a hill. Could be the wrist pin bearing. The crank bearings seen fine. I am using 24" wheels so the gearing is lowered a little, revs a little high but I like the better low end. It is fourstroking at full throttle and I am still breaking in. I am using 87 octane, don't know if the noise could be detonation but I would suspect that if it was loud under load.
 

crassius

Well-Known Member
Sep 30, 2012
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a mechanic's stethoscope is usually cheap & has a probe that extends to 3 or 4 feet to help locate the source

also, sound deadening inserts are available for these engines

some of them are just loud
 

supercub

New Member
Nov 1, 2012
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New London, CT
Turns out to be my crank, it locked up on the rod main. Must have blown out the rollers. I couldn't pull the mag rotor or the small gear, looks like a small custom puller is necessary.
 

biknut

Well-Known Member
Sep 28, 2010
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Dallas
Turns out to be my crank, it locked up on the rod main. Must have blown out the rollers. I couldn't pull the mag rotor or the small gear, looks like a small custom puller is necessary.
Where did you get the motor from?
 

GearNut

Active Member
Aug 19, 2009
5,104
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San Diego, Kaliforgnia
If your engine is from a brand new kit, follow bikenut's advice before taking apart the engine. Try to get it warranted. Most all warranties are void if you go tearing into the engine even a little bit.

That said, here is some info on removing the parts you had in mind if you choose to take it apart anyways.

A special tool is needed to remove the small gear.
See the top left corner: http://thatsdax.com/ENGINE_KIT_PARTS_PAGE_4.html

A battery terminal puller works really slick for removing the mag rotor if you remove the mag coil first.
http://www.toolsinstock.com/admin/images/AK419.jpg
 
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supercub

New Member
Nov 1, 2012
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New London, CT
I brought it from boygofast a few years ago but just started using it as I found Raleigh moped wheels that fit which included a rear hub sprocket/drum brake. I have one of those pullers that came with another kit I just recently brought for another bike I was going to build. Don't think that small gear has threads inside but will check. I tried to pull it before to see why the gear stuck way out from the large gear. Will try a terminal puller for the mag but might end up using it for parts and see if I can double the mags and use one for lights as I ride at night alot.
 

racie35

Active Member
Nov 17, 2012
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usa
we can get that apart for you at our car shop in montville if you're gonna take it apart instead of sending it in..happened kinda quick didn't it? what oil were you using?
 

biknut

Well-Known Member
Sep 28, 2010
6,631
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Dallas
I brought it from boygofast a few years ago but just started using it as I found Raleigh moped wheels that fit which included a rear hub sprocket/drum brake. I have one of those pullers that came with another kit I just recently brought for another bike I was going to build. Don't think that small gear has threads inside but will check. I tried to pull it before to see why the gear stuck way out from the large gear. Will try a terminal puller for the mag but might end up using it for parts and see if I can double the mags and use one for lights as I ride at night alot.
I think you will in fact find threads inside the small pinion gear. They all have them.

Usually if you remove the magneto coil, and the bolt on the magneto rotor, the rotor will not be very hard to remove. If I can't get it off by hand, a little light prying with a screwdriver will usually loosen it enough to yank it off with your hand. Try 2 screwdrivers, one on each side. Maybe a little WD40.
 

crassius

Well-Known Member
Sep 30, 2012
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USA
the rotor should come off rather easily, but sometimes the woodruff key in there will be sucked up by the magnets such that it binds against the laminations of the rotor - use a sewing needle to reach in the slot & hold the key down out of the way
 

supercub

New Member
Nov 1, 2012
56
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New London, CT
I was using 2 stroke motorcycle oil from NAPA, been using it for years. Started making noise within the first 10 miles. Will try to dismantle myself but will use the new motor on this bike and see how it lasts. It looks like the quality improved alot from the older one.
 

Skyler

New Member
Jul 14, 2019
18
8
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Colorado Springs
Did you fix this noise? I'm getting a run run run run run vibration noise that is paced with my reflector passing my fork. Not necessarily when it passes my fork just a measure of it's timing. At top end it seems to settle down significantly.