4-S Clutch Flyweight Replacement

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#1
So I'm thinking of replacing the whole clutch 4S flyweight. Problem is, i was only able to partially unscrew the center bolt...and if I use the 3-jaw clutch puller...then I'm afraid I might snap or strip the center bolt. Any helpful suggestions ??
 






bakaneko

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#6
a picture might help. the center bolt should come out after you put a screwdriver into the slot on the face plate...
 

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#7
a picture might help. the center bolt should come out after you put a screwdriver into the slot on the face plate...
Doing that too. Anyways.......

Had a chance to look at the schematic transmission clutch drawing, and the only things there was the short bolt screw, outside washer and lock washer....nothing on the opposite end such as a nut screw that would be the cause of the issue. However, something sounds like its revolving along with the bolt as I attempt to unscrew it. Just out of curiousity, I attempted to screw the bolt back in....and it no longer does that either. So what I'm left now.....is a SPINNING SCREW

_
 

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#8
So I finally was able to take off the clutch flyweight, like doing the really simple and obvious....sticking a screw driver down the spark plug hole. Now I noticed there's some loctite threadlocker in the shaft. Would it be a good idea to reapply loctite threadlocker with the new clutch flyweight replacement ?

_
 

CrazyDan

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#9
A rope in the hole is alot safer and less likely to poke a hole through your piston, or gouge it bad.
Edit: the direction the shaft and clutch spin tightens the bolt at all times, unless your transmission does engine braking.
 

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#10
Well, restored the engine power with the new flyweight replacement, but am wondering now just how long I can maintain the new clutch pads. Perhaps giving some more slack on the chain maybe ?? Some have suggested replacing the pads every 100 miles...which would give new values to the term: insanity.

_
 



CrazyDan

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#13
Your clutch stall speed is the rpm the clutch begins to engage the bell. It slips till full engagement. You want to avoid the rpms in between as much as possible to allow your clutch to last. Get up to full engagement then let your rpms climb a little more before cruising. I have a buddy that didn't like going fast and stayed around 15-20 mph all the time. His gear ratio made it so the clutch wasn't fully engaged till 19 mph. His clutches lasted a couple weeks each. I changed his gear ratios up and yes engine rpms are alot higher than before when he would hang around 20 mph, he now does 27 mph vs 40+ max. Take-off and hill climbing improved greatly as well.
 

CrazyDan

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#14
Also, use caution when working with a burned out clutch, most cheap clutch pads are made with asbestos. DO NOT BREATH IN THAT DUST.
 

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#15
Do you mean changing gear ratios on an 18 speed mountain bike ?? I don't believe I ever use those with the engine running. Like I sez, just got one 44T...and the single chain hoot trans, dats it.

Your clutch stall speed is the rpm the clutch begins to engage the bell. It slips till full engagement. You want to avoid the rpms in between as much as possible to allow your clutch to last. Get up to full engagement then let your rpms climb a little more before cruising. I have a buddy that didn't like going fast and stayed around 15-20 mph all the time. His gear ratio made it so the clutch wasn't fully engaged till 19 mph. His clutches lasted a couple weeks each. I changed his gear ratios up and yes engine rpms are alot higher than before when he would hang around 20 mph, he now does 27 mph vs 40+ max. Take-off and hill climbing improved greatly as well.
 

CrazyDan

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#16
Your hoot transmission has a 3:1 reduction with a 10t output going to a 44t for a total gear ratio of 13.2:1. You are cooking your clutch till 20 mph at that ratio. You would be much better off with an 18:1 ratio or higher. Yes you'll be at around 6k rpm to do 25 mph, but your clutch will thank you.
 

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#17
I get confused if the transmission is either a 'multi-speed'...or a 'variator'. Anyway, the main sprocket on the dual chain BB, has 41 tooth and a shaft sprocket of 6 tooth...which supposedly translates to a higher gear ratio. The issue I had however, with this larger trans, is that it would only get to 18 mph at 6500 RPM and not engage or revert to a lower RPM cruising speed afterward...which is what a transmission is normally suppose to do.
 

CrazyDan

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#18
You don't get multi speed with a simple single speed transfer case unless you get jackshaft over or use a reverse rotation pocketbike transfer case.
Both of what you have are single speed transfer cases. You can choose what gear you are stuck in, pretend you have a broken transmission that can only use 1 gear: do you want to be able to climb hills in 1st gear but be limited to a low speed with high rpms? Stuck in 3rd, kinda slow on takeoff, decent speeds and will slow down on hills but maybe take them but only if you pedal. Or stuck in 5th (your gear ratio), destroy your clutch some every time you accelerate from a stop, very slow acceleration, high top speed and no ability to take hills without moving into the clutch destroying rpm range.
Your choice.
 

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#19
I had the bike..the one with the single chain trans, on a bike stand, and noticed that the clutch engages and disengages at around 4000 RPM. So I'm assuming when actually riding, that whenever the engine approaches 7000 RPM...then settles down between 3 and 4, then this is the optimal sweet spot for cruising. Checking the tach then, is about the only way I see of preventing a clutch blowout.


You don't get multi speed with a simple single speed transfer case unless you get jackshaft over or use a reverse rotation pocketbike transfer case.
Both of what you have are single speed transfer cases. You can choose what gear you are stuck in, pretend you have a broken transmission that can only use 1 gear: do you want to be able to climb hills in 1st gear but be limited to a low speed with high rpms? Stuck in 3rd, kinda slow on takeoff, decent speeds and will slow down on hills but maybe take them but only if you pedal. Or stuck in 5th (your gear ratio), destroy your clutch some every time you accelerate from a stop, very slow acceleration, high top speed and no ability to take hills without moving into the clutch destroying rpm range.
Your choice.
 

CrazyDan

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#20
If you notice that the clutch engages and disengages at around 4k rpm then why cruise at 3-4k??? That right there is churning your clutch. You will want to stay above 4k rpm.
 


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