Clutch cable and clutch adjusting procedures.

GoldenMotor.com

GearNut

Active Member
Aug 19, 2009
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San Diego, Kaliforgnia
My best guess is you need to turn the idle speed screw inwards, towards the carburetor slide, to increase the idle speed.

If the cable it too tight it can cause 2 problems:
1. The release assembly never gets to fully relax and the resulting clutch spring pressure on all the parts involved causes them to wear out faster.
2. The clutch may not be able to fully lock up and it will slip under power.

The cable being too tight will not affect the idle speed.

The flip side to this clutch scenario:
If the cable is too loose it can cause the engine to die because the clutch cannot fully dis-engage and it will drag, placing a load on the engine that it cannot overcome during idle speed which has a very low power output.
Also, a clutch that is out of adjustment can also drag causing the engine to die.

9 times out of 10 the clutch has been adjusted good by the factory.
Never try to adjust the clutch without first adjusting the cable and always double check your adjustments.

A brand new cable will stretch as it breaks in and the need for frequent cable adjustment is to be expected on a brand new engine/ cable. After the cable settles in it will hold an adjustment for a long time.
 

2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
Just a hint, but with a new cable I leave the lever lock on when the bike is parked. That hastens the stretching process and keeps down the number of times you'll need to adjust cable tension. They'll stretch to their max length pretty quick if the clutch is left locked whenever the bike is parked.

Tom
 

sboricic123

Member
Apr 15, 2013
172
3
18
Bailieboro, Ontario
New Grubee 66cc.
I followed Gearnut's instructions to adjust the clutch. It runs fine but I would smell rubber burning. So I took off the flower nut and plate and noticed the friction pads had been rubbing a bit. When I have the clutch engaged, the back whell does not turn. So, is it common during break in to smell the rubber burning from the pads or do I need to do some more adjusting?
 

2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
The smell is normal.
I hope you get the clutch adjusted properly after taking it apart.
I usually try to dissuade people from playing with the flower nut until they have a firm understanding of how it works and how to adjust it properly. Good luck and follow the advice given in the tutorial. You should be good.

Tom
 

sboricic123

Member
Apr 15, 2013
172
3
18
Bailieboro, Ontario
Thanks Tom. I thought I'd just confirm it was normal before riding it and wearing them out. I noticed only a few of the pads were wearing down too. I had to remove bits of loose rubber that was around them.
 

2door

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Staff member
Sep 15, 2008
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Littleton, Colorado
Too much grease on the gears can cause some smells too and clutch slipping.
If the friction pads look glazed (shiny, wet) you might try cleaning them using spray solvent made for cleaning disc brakes (Brake Clean) is a brand, not sure of the spelling.

Roughing up the pad surface with a course grit sandpaper will also help. Don't take off too much material, just enough to roughen the surface a little.

Tom
 

joelogger2

New Member
Apr 18, 2013
33
0
0
montana
its like the shaft the flower nut is on is extended alll the way and you can do all you want you cant move the clutch arm:-||:-||:-||:-||how do i fix that is there an adjustment in the clutch shaft itself
 

joelogger2

New Member
Apr 18, 2013
33
0
0
montana
dont reply on this if youn have notin to say about what my problem is and how to fix it dont care about otherpeoples problems that dont help me
 

joelogger2

New Member
Apr 18, 2013
33
0
0
montana
clutch shoes are new just replaced i replaced them when my clutch arm was under neath carb and couldnt b adjusted any more how do i fix that i increased the leanght of the bucking bar to give it more through and nothin cant even move the clutch arm when put back togethere i also tightend the flower nut real tight on the pads to prevent further slipping is the a nother adjustment to make with the actual shaft itsself:-||
 

crassius

Well-Known Member
Sep 30, 2012
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check that the flower nut isn't on the rod so far that when released it is stuck against the shaft so that the outer pressure plate never gets to the pads
 

KCvale

Well-Known Member
Feb 28, 2010
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Phoenix,AZ
clutch shoes are new just replaced i replaced them when my clutch arm was under neath carb and couldnt b adjusted any more how do i fix that...
Your clutch arm should not be able to go in clear to under the carb.

i increased the leanght of the bucking bar to give it more through and nothin cant even move the clutch arm when put back togethere...
Huh?

i also tightend the flower nut real tight on the pads to prevent further slipping is the a nother adjustment to make with the actual shaft itsself:-||
Man, you really should read how the clutch works.

On the left side you have the engage arm in the side cover.
The drive sprocket has a pin poking out of it.

The flat spot on the engage arm lines up against the pin with the clutch released.
Pull the clutch lever and the engage arm shaft turns, pushing the rod in the middle of the sprocket.

If your pin does not stick out you probably lost the single ball bearing that goes behind the pin.

On the right side you have the flower nut, your only internal adjustment.
With the clutch engaged you turn it in until it contacts the pads, then back it of a 1/4 turn and put the set screw in.

So, with the clutch released the silver pressure plate goes against the pads and drives you.
When you pull the lever it moves the pressure plate out a mm or 2 to disengage the engine from the drive sprocket.
 
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2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
dont reply on this if youn have notin to say about what my problem is and how to fix it dont care about otherpeoples problems that dont help me
Not sure who this was directed at but it isn't the way to get help here. You need to go back to your original thread and read what others have suggested. http://motorbicycling.com/showthread.php?p=589308#post589308

Also please don't start a new thread in another area asking the same question. Multiple and duplicate posts will be removed.

The link to this tutorial was offered to assist you in properly adjusting the clutch. You might take the time to read it and try the steps outlined there.

Tom
 
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mezzenger

New Member
Nov 15, 2015
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Winchester, VA USA
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And I would like to add some further info (with pics) ;-}

Basic Cable Design

A cable has two parts.
There is the actual inner cable with connectors on each end in this case to the clutch handle and the clutch arm, and an outer cover.

The outer cover is not for decoration!
It is an actual crucial part of a cables mechanical ability to transfer force from one place to another in a flexible form!

When you 'tighten' a cable with in-line adjusters you are not tightening the inner cable from point A to point B, you are adjusting the difference between the inner and outer cable parts.

For example the kit locking clutch lever has an adjusting screw and locking nut.



The adjusting part is the cone shaped part the cable cover fits in, the locking nut is the bigger ring.
Make sure this is screwed in as far it will go before adjust the brass lock connector on the clutch arm side.

If your clutch won't disengage after some inner cable stretch and outer cable shrinkage you can tighten it up by twisting the cone out and snugging the locking ring up against it to compensate.

There is also one that is mounted on the motor itself under the Carb but it much harder to get to.

Once the cable is adjusted

It is very common for the grease in the bearing between the clutch plate and outer gear to the motor to dry on the literally slow boat from China trip to the US and warehousing, and pulling the lever does not seem to engage the clutch to disengage the motor from the drive sprocket.

This is usually not the case at all and the clutch pressure plate does indeed move away from the friction pads, the dried grease just has the shaft locked to the gear.

Pop off the right cover.



Pull your clutch lever, that big sliver plate should move out towards you.
If it doesn't go back to cable adjusting until it does.

Now pay close attention to the locking screw and flower nuts position, mark them if need be for reference, then pull the flower nut lock screw and unscrew the flower nut.

To make this easy lock your clutch lever in the engaged position and you can twist it off with your fingers if you push the plate down with your hand while doing it.
The same goes for putting it back on.

Pull out the pressure spring and you find the business end of what makes a clutch work.



Understanding the Clutch

Using that pic and my terms as reference, the little gear is the actual motor crankshaft output.

The large gear is a plate that holds all of those little friction pads, and it 'floats' on a bearing that divides at the 'Bearing Seam'. That is usually what dries out and locks the motor to the drive train and needs breaking free.

The silver pressure plate you removed earlier rides on the those 3 'Clutch Plate Float Guides' so it can be pushed away from making contact with the pads, but still staying connected to the output shaft, thus disengaging the motor from the drive side, but making contact when you release the clutch so the plate makes contact with the pads to the big outer gear.

To Free Up That Bearing...
A long flat head screwdriver works dandy for me.

All you need to do is use two the Floating Guide posts for leverage and without the motor gear moving.
CRUCIAL IMPORTANT NOTE!!! Do NOT use that center Disengaer Shaft as a leverage point!

Give the screwdriver a hard push down and it should break free.
If the motor gear moves you need to stop that from happening, the point is to break the bearing free.
The gears need to not move, just the inner part to the drive sprocket to break it free.

NOTE: if your drive train is hooked up to the wheel lift it so it will turn, that inner shaft goes directly to it.

The common practice to keep the motor locked is to put a wooden dowel of some other thing that wont scar the cylinder wall but block the piston moving down the cylinder head from the plug hole, but as I look at this it seems to me you could just wedge a piece of plastic or something in where the two gears meet so they couldn't turn.

It's not like you are breaking a piece of metal, it is just freeing up dried grease in a bearing.

Once you have it free

Clean out all the gunk between the pads and put a liberal amount of new grease (not oil) on that Bearing Seam and the gears.

Adjusting the Flower Nut

Put the spring and plate back on and put the flower nut about where it was.
Lock your clutch in and roll the bike around, does it roll free?
If not, back the flower nut off 1/4 turn until it does.

Once it rolls free, let the clutch lock out and try.
Does it engage to the motor?
If so put your set screw back in (lockTight it of you have have it) and button it up, you are done.

Remember, if you start getting clutch loss, you have two places to adjust for it, the clutch lever is just the easiest.
Those are some really nice hand grips yu have there KC. Are they still available somewhere?
 

RockNRoller

New Member
Jun 19, 2017
3
0
1
36
Haven't got to fire up the new build yet. Having issues.
1. Clutch lever is parallel with engine. Seems a bit tight. When I let out the clutch, I don't hear my piston moving as the bike rolls. Do I have the clutch lever pulled in too tight with the cable?
2. During first try to fire up, (Highly torqued) tensioner moved and broke a spoke. (Can be very dangerous) I cannot stress that enough. Be cautious.
3. Is there a location that best suits where the tensioner should be placed? Closer to sprocket? Closer to engine?
4. Something appears to be rubbing somewhere to do with the chain. Rear fender has been trimmed with metal snips. Chain is close but doesn't rub the tire.

Any advice would be greatly appreciated. I'm recovering from a broken ankle and can pedal the **** out of a bike but I need this as my daily transportation for distance. Thank you.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
if chain is aligned properly and adjusted at the tightest spot, there is no force to pull the tensioner down - check all that

if frame has skinny chain stays, I sometimes will cut an inch or so of old handlebar and split it into two shims to put under tensioner

if bike rolls without motor turning, either clutch is not grabbing or something is loose on one of the shafts (often a missing woodruff key too) - open both covers and see where turning stops
 

Natasha

New Member
Feb 12, 2018
3
0
1
39
Okay so I want to adjust the clutch but I remove the cap to the sprocket side instead of just loosening the cable so my pin is stuck out how do I get my PIN to go back in
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
put the cover back on and tighten the three bolts to push the bar in

read about the full set of steps to adjust cab;e and flower nut and getting the clutch are pointing straight back