whats all this noise about

[Johnny_Boi85]

Hey guys started hearing what sounds like a dry lose bolt coming from the motor. its an internal noise. I know its nothing to do with the head as ive recently had it off due to carby issues. The noise is there from start up cold to hot and just when idling. A little throttle makes this sound go away. I hope thats enough info so u may know what the problem could be so I can start trouble shooting it thanks

 

[Johnny_Boi85]

Oh and it does the same thing no matter what gear its in and whether the clutch is on or off

 

[my67xr]

what engine ?
and is the noise from the clutch side ?

 

[Johnny_Boi85]

Atomik 150cc bike. And not sure where abouts its coming from but I just started it and it dosnt go away when i give a little throttle. I have a feeling has something to do with the clutch maybe

 

[my67xr]

it could be a loose clutch nut, or maybe a worn clutch basket ?
you'll need to lean the bike over onto its' left side, take the kickstart lever off and take the clutch cover off.
you'll see the basket there, see if you can wobble it at all, it should move a little bit
if it moves a lot, it could be the Clutch retaining Castle Nut that is behind the thrust plate and bearing

otherwise it will need the whole clutch cover to be taken off and look at the clutch basket.
hold the alloy part of the basket and with your other hand try and move the big gear on the back.
if there is movement between the 2 parts then the basket will need to be repaired or replace the clutch.

 

[Johnny_Boi85]

Ok sweet as I will give it a go tomorrow im keen as on learning all this stuff and having a go at it. I will let u know how I go and appempt to post pics if I run into any dramas

 

[Johnny_Boi85]

I pulled the cover off and there is movement. I can push it in and out about 3mm and turn it left and right about 1mm either way. Do u know of a post with a full quide regarding clutch replacement or anything like it to quide me though it

 

[zwebx]

I pulled the cover off and there is movement. I can push it in and out about 3mm and turn it left and right about 1mm either way. Do u know of a post with a full quide regarding clutch replacement or anything like it to quide me though it

my67xr has a post up in tutorials on basket rubber replacement..
Or you can but a 6 plate clutch replacement seems to be the go imo.

 

[my67xr]

Undo those 4x 10mm headed bolts and take the plate with the bearing in it off.
Then check if the Castle nut behind it is tight

 

[GooseMan]

Sounds to me like a loose nut as my67xr said cause it moves in and out.

 

[Johnny_Boi85]

The castle nut is tight as so ots not that. Should it have play moving in and out a bit?.

 

[zwebx]

The castle nut is tight as so ots not that. Should it have play moving in and out a bit?.

a tiny bit, not much the basket is actually mounted on "rubber" rings to absorb some forces to stop the gearbox/crank jarring up.. when these rubbers fail you get this movement. and it is unacceptable.. causes exhilarated gearbox wear and chain wear.

 

[coolmodee01]

How zwebx ?

how does worn out rubbers cause exhilertated or even accelerated gear box wear?

it's just not possible yes it does dampen the shock load caused by the clutch but the clutch can slip as much as it needs to and the crank is disengaged from the gearbox while the gears are changing in mesh

please confirm your findings?

he he he he :boink:

:focus:

Righto also check your cam bolts they may have come loose. could be a bad bearing in the gear box. could also be the stator rubbing on the backing plate but you would notice that from new.

my money is on a clutch gear as the fella's above have stated

o o o i have also seen the circlip that hold the kick start gear on fail and make bad noises to

 

[Johnny_Boi85]

Is the castle nut a left hand thread by any chance Im having trouble undoing it

 

[my67xr]

no, it's lefty loosey to undo it.
you need to give the castle nut a decent hit with a hammer and big flat headed screwdriver in one of the cut outs.
otherwise you could buy the correct tool to do it as well.

is it a Lifan 150 ? could be a cracked r/h engine case too ?
do you have the whole side cover off ?

 

[Cordogs]

An impact screw driver is you're best friend here!

 

[zwebx]

How zwebx ?

how does worn out rubbers cause exhilarated or even accelerated gear box wear?

it's just not possible yes it does dampen the shock load caused by the clutch but the clutch can slip as much as it needs to and the crank is disengaged from the gearbox while the gears are changing in mesh

please confirm your findings?

he he he he :boink:

same as cush drive, reduces bad harmonics and increases gear life and chain life instead of pulses you get a smooth cranking action or well.. smoother..

 

[GooseMan]

it is true as far as I know, and that is why road bikes have rubber mounted sprockets/ hubs, and that is why if you go to motard it can greatly reduce your gearbox life, according to honda anyway.


Anyway, could be rubbers gone, just hard to believe it only has 1mm of rotational play, if it is the rubbers. Does the bike run poorly at all or viabrate, check engine mounts as well.

 

[Johnny_Boi85]

I think it is a lifan it is a 150cc just not what kind it is. atm I only have to clutch cover and pressure plate off leaning over the left side so oil dosnt come out

 

[Johnny_Boi85]

its not mounts the sound is coming from around the clutch area but not sure where yet