Slight knocking noise coming from clutch end

Hi guys I've got a speedfight 2 100cc and it has started knocking from the clutch end I'm looking for some advice on what it could be or what to look for when I strip it down thanks in advance

 

does it knock when you push it forward and back? or only when the wheel is powered by the engine? sounds like a clutch/gearbox bearing to me

 

Take the belt off, start the engine. If the knock is gone its the clutch/gearbox issue as scuba says, or maybe a rear brake shoe issue.

 

Hi guys it dose it when it's ticking over at a stand still and I have disc brakes on the back the knocking sounds like something is knocking on the cover

 

summats sounds loose then
best whip the cover off and take a look see before all hell breaks loose

 

Checked everything is tight I'm sure it's the gear box this is it

 

Not possible to be the gearbox if the bike is stationary and the rear wheel is not turning. Take the belt off and see if the noise is still there. If its gone the its the clutch assembly, if its still there its something else.

 

Cheers for your reply I've ordered the clutch removal tool witch I'll get tomorrow so I'll check the clutch inside I think the clutch is ok as it's hard to pull it back witch over been told means the clutch is good

 

Hi guys so I got the clutch and this is what I've found the springs are ok and have tension I'm hoping that's the cause of the knocking so I've ordered a new 1

 

thats very strange looking, what did the clutch bell look like? looks like that got oil on it and just got too hot due to slipping.... or maybe it was stood for a very long time?

 

The bell looks fine all smooth in side

 

Holy crap on a cracker
Never seen clutch slippers that bad.
Replace the clutch springs as well. For the sake of £3 its a no brainer.
But I'd still be surprised if that is the cause of the knocking, unless a clutch spring is broken of course.

 

All the springs are good the middle cog inside the gearbox has a slight bit of movement so now I'm thinking the slave it sits in has worn

 

The gears always have a little backlash in them. I suggest that you check the rear axle for play, as a knackered outer bearing will cause the axle to move around a bit, causing gearbox noise. When I rebuilt my TKR's engine and gearbox, the outer bearing was knackered. I fitted a new one with double rubber seals instea of the metal seals, to keep the dirt out.

 

Thanks for replying There isn't any play when I try and wobble the wheel or do you mean strip it down and check

 

I took the belt off and there is no knocking sound it sounds as it should I've replaced the clutch and it's still knocking at a stand still but when I rev it the knocking noise goes

 

It could be play in the pins or slots of the rear pulley, the part that is inside the pulley. There are pins that run in guide slots to change the drive ratio and the noise could be down to wear in those parts. Once the variator takes up the clack in the belt, the pull of the belt takes up the wear and the noise goes away. They can stick (mine does) and I plan to remove mine and fit a Nakaru sports pulley that I bought some time back.

 

Checked the pins all seams fine I took the final drive shaft out and the bearings are knackered but there is no number so I can't match it I've looked on Google and I'm getting 2 different sizes can anyone help with the right size pls it's the bearing that goes in here I really appreciate your help

 

You need to measure the bearing outside diameter, inside diameter and thickness. I think it's a 6203 or 6204 bearing from when I rebuilt my TKR's engine, but please check. The original bearing is a metal shielded 'Z' type, I would recommend that you go for a '2RS' (rubber sealed) type as a replacement as they are more water and dirt-tight and will keep the gear oil in. I fitted 2RS bearings to my transmission. Only buy a decent brans such as SKF, NTN, FAG or similar and I recommend Simply Bearings as a decent web site to get them from.

Edit: I Just checked my Simply Bearings account history. It was an FAG 6202 2RSR (15x35x11mm) bearing that I bought for mine (my bike is 50cc so check the output shaft diameter) and I also bought a 22x35x7mm Nitrile Rubber Rotary Shaft Oil Seal with Garter Spring R23 / TC to go with it. Total cost should be about £11 from Simply Bearings.

 

The 2 sizes I'm getting when searching are inner 20 outter 42 and inner 25 outter 47 mine is a 100cc 2005