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Discussion Starter · #1 · (Edited)
I decided to create a new topic with the proper title about the Chinese performance 2 shoe clutch.

As you all know the 3 shoe clutch has the most ridiculous and rather annoying problem: it often snaps springs and does so rather quickly.
One solution is to use a 2 shoe clutch or buy top of the line clutches that cost more than the engine itself.

The 2 problems with the Chinese performance 2 shoe clutches is 1. that they engage at a rather very high RPM and 2. they engage loosely due to the very high spring pull, so the clutch ends up rubbing against the clutch bell.

For those of us who want to engage at the same RPM as the 3 shoe clutch which will most likely solve both problems 1 and 2 as well and create a more solid engagement, I was thinking maybe we can replace the strong springs currently on the knock-off performance clutches with some looser weaker springs. Unfortunately in the knock-off world, spring colors does not always make any difference and all springs end up being pretty much the same and too strong, but correct me if I am wrong as I have not tested this myself (weaker Blue vs stronger Red knock-off springs. I currently have Red.). So I'm thinking of outsourcing some springs of our own from either Ebay or a local hardware store. Hopefully such springs are cheaply available.
One can also buy a good looking long spring and possibly snip it in half or something to make it the correct length.

If done correctly, I imagine the clutch snapping problem would be completely gone!

What is your take on this?

This is more of a request than a solution just yet because figuring out which springs will work will take a couple of tries using different springs to find the perfect fit unless an enthusiast guesses correctly the first time.

After all, I really hope there is a cheap solution to the 3 shoe clutch spring snapping problem that will be gone once and for all for the most part.

If something works out to be good sometime later I hope to rename the title to something like Cheap 3 Shoe Clutch snapping springs solution using a Chinese Performance 2 shoe clutch.

These can be had for just $20 shipped, plus the spring mod to put looser springs.
 

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All I have to contribute to this topic is that the hp chinese clutch is fpor racing only...theres no flicking thje throttle with it for very long as they tend to overheat fast.............I have one in my 5 port trophy cag and my EvilWasp cag>>>They both had to be diosassembled and modded to operate freely thus making them react as they should.....The 2 shoe clutch is for racing and aggressive riding



Thres ways to mod the stock clutch to withstand clutch spring snappages..................

Of you look at the shoes theyre rather rough casted...if you take a dremel and dremel away the face of the shoe that touches the spring...eliminating this rub will eliminate heat

Ifyou look in the shoe pad holes where the spring goes youll notice it has a sharp edge...that edge is bad..I use a small precision file to smooth out these rough edges and the springs last so much better........

Dill some lightening holes which also cool the pads equally so theres no extra heat build-up that causes clutch fatigue.This will add some stall speed and the amount needed can also be customized by lessening the diameter of the clutch but this will require tightening of the springs slightly.....Good Luck





 

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Discussion Starter · #3 ·
Thanks for pointing that out CAM2. I have a feeling the 3 shoe clutch would engage better than a 2 shoe knock-off clutch too since it has more pad material.

I will give that a try.

"The face of the shoe that touches the spring"
Where is the face of the shoe exactly? (Can you edit the image and put red circles around what you are describing?)

Instead of using a small precision file since I don't have one, maybe I can use a small drill to smoothen out those shoe pad holes.

What is stall speed?

How long have your springs lasted you? (Approx how many miles?) Are there any particular springs you would recommend that have guaranteed strength and long life?
 

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If you look where I drilled the single holes in the arms of the shoes....Those are places where the spring rubs the shoes aswell as the thick aluminum above..I drilled in cooling holes aswell as dremeled away some of the bulky profile and made it more even faced

If you notice how polished the insides of the screw holes and the faces are ...thats a properly blueprinted clutch...Also look into the holes for the springs.Theyre open and smooth.....My clutches perform flawlessly



Stall speed is how many rpms it takles for the clutch pads to hit the bell......My modded clutches grab 750-1175rpms higher over stock depending on how lightened I make them...These pads are over 4 grams lightened...that might not seem like much but its good for an extra 900rpms over stock lock-up
 

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Discussion Starter · #5 · (Edited)
Ok makes sense.
Do you still get spring snaps once in a while? Did this become a rare event?

As for the spring rubbing part, are you talking about that thing that looks like a half circle sticking out?
That's the part that you dremel away on all 3 shoes?

I'm getting a little excited that I will finally be able to fix the spring snapping issue.

Also for lightening holes, does it have to be in exact locations on all 3 shoes or can it be in approximate locations?

Some pads have brown material while others have grey material. Is there any difference?

Does the clutch bell ever wear out? Because if it does that would mean a new gearbox.
 

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Discussion Starter · #6 · (Edited)
Well here it is. I finally did something to my clutch. The picture quality may lack, but it's seen that I smoothened it out and made the clutch spring holes a little larger with a drill bit which also made them smoother.

Approve that I did things correctly. And please answer the questions in my previous post.

Is it possible to get the pads themselves for cheaper than an entire clutch? A complete clutch is like $10 shipped, but I'd like to know if I can get a bulk pack of pads for a more reasonable price. As you can see my pads are half-way worn out aren't they.

 

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Ok makes sense.
Do you still get spring snaps once in a while? Did this become a rare event?

As for the spring rubbing part, are you talking about that thing that looks like a half circle sticking out?
That's the part that you dremel away on all 3 shoes?

I'm getting a little excited that I will finally be able to fix the spring snapping issue.

Also for lightening holes, does it have to be in exact locations on all 3 shoes or can it be in approximate locations?

Some pads have brown material while others have grey material. Is there any difference?

Does the clutch bell ever wear out? Because if it does that would mean a new gearbox.
Ive been riding the stand-up scooter that has a 3 shoe cag type clutch on a piston ported engine a few months ago maybe a tad more........It has a wildly modded clutch and has been ridden for many-many hours and Ive yet to break a spring...The piston ported clutch spring lasted alot more modded than not aswell..........

Those pics you showed of the work you did on the clutch looks pretty good.........Dont be scared to drill holes to ligghten up the shoes,,,,They dont last very long.......

As far as getting clutch material theres companys that sell just the lining but it costs alot because its sold in bulk quantitys that are so huge youll never use all those pads in two lifetimes.............LOL

I simply buy cheapo chinese clutches in bulk and pre-mod them.............LOL
 

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I'm interested in knowing where you get them in bulk.

Approximately how many miles can a single clutch last without replacing the pads?

Do clutch bells ever wear out?
I get my clutches in bulk from ebay shipped from China...5 2 shoe hp clutches for $70 w/shipping included;-Theyre $30 each if bought seperately....10 stock aluminum clutches for $50 w/shipping included...10 stock steel clutches for $33.00w/shipping included........Just gotta know how to find the deals at times......the deals arent always there...they pop up from time to time.....

My scooter I say has atleast 75-90 miles on it since I changed the clutch to a three shoe in the scooter and knock on wood no spring failure so far..Before I changed the clutches over to three shoe I had about 50 miles on the two shoe and had 3 busted springs in that timeframe.....





 

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Discussion Starter · #10 · (Edited)
You mentioned steel clutches. Hmm I wonder why you would use a steel clutch when aluminum is by far lighter and engages at a higher rpm?

Do you use any steel clutches at the moment with springs that have lasted long so far?

I have a steel clutch that I put to spare parts because it engages at idle rpms no matter how much I lower it plus it snaps springs quick.

Do clutch bells ever wear out?
 

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Everything wears out, the bell last longer than the shoes if you run them hard. Everytime I pull the bell, I ruff up the shoes and bell w/ 100 grit sandpaper.
 

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Discussion Starter · #15 ·
Warped from heat? If I take long rides then this could be a problem? 10 mile rides average. I don't think they're that long.

Update on the Chain Tensioner:
Looks like I found out what to use my spare clutch springs for (the ones that were stretched out from the very first disaster that occurred when I just began this project).



Also you can see a bolt right above the top of the chain. I put nylon spacers on the bolt. This was necessary to prevent the chain from rubbing on the frame. I tried not to go too far or else I suspect the nylon washers would wear out very quickly.

The HD Springs tension it quite hard so I tightened the chain by hand and didn't even stretch the spring when mounting it (well just a little).
Now this should hold good. If this was a bad idea let me know. Maybe I can use some lighter clutch springs like the stock ones or another spring only if necessary. But if this will hold up nicely I can stick with it until the spring snaps (Joke lol).
 

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Not really..The only thing that fatigues clutches is sticky shoes and always being on and off the throttle....The easier you are on the throttle and slip the clutches the more heat the clutch generates........With these clutches you need to stab the throttle 1/2 or better and hold it steady...Flicking the throttle on and off is the biggest killer of clutches and springs

If you set the clutch for the lowest lock-up rpm's possible you wont get quick off the line power but you get the luxary of messing around with the bike doing tight slow turn maneuvers n such while keeping clutch heat down more........

Clutchbells get thinner and wear down too...as they constantly heat and cool the cheap chinese steel starts to warp slightly...You cant see it but you can feel it when you ride...Theyll be a slight shake and shimmy when it drives..
 

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I have had to turn my bikes off alot more times for smoking clutches and over heated clutch pads, then the engine getting to hot,lol.
 

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Hi guys. Here is my problem. My son (5 years old) has a Chinese mini dirt bike (39 cc) with 3 pads clutch. You noticed these dirt bikes have a kind of a gear box because the speed is not that important but the 'power'. The problem is that we don't have that power :) because the clutch slips (in my opinion).
Here is the test I did. I lifted the rear wheel of the bike (from the ground) and I rotated the throttle in order to increase the engine rpm. The rear wheel increased its rotation speed also, the more throttle the more speed. Then I left the rear wheel on the ground and I pushed the sit with my right hand while I rotate the throttle with my left hand. If I push harder the bike won't move even I increase throttle. My son's weight is ok to ride on flat places but it's hard on ramp places.Looks like the clutch doesn't engage strongly.
I read and did almost everything written here. I mean, I checked the springs route and looks like the clutch shoes moves freely. I assume the springs are rigid and they don't let the pads to firmly engage on the bell. What do you suggest for a mini dirt bike in this case? Lighter clutch shoes or softer springs? Clutch engagement at lower rpm or higher?
I would like the clutch to start engage at a some rpm range and firmly engage after. It's obvious the settings for a dirt bike are different from a street pocket bike but the principles are the same. If an adult can ride a pocket bike on the street then a child should be able to ride a (same size) dirt bike on some off roads. Does anyone experienced my problem? Any suggestions?
Regards,
vapi
 

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Get rid of the lighter aluminum clutch and get yourself a heavy duty steel one.....The clutch engages at a lower rpm and the heavier arms make better contact grab on the bell.......If you put the new hd clutch sand the bell with 100 grit to deglaze it or youll glaze-up the new pads and get some slip..........Right now you can deglaze the pads and bell for better grip right now...you cant ****yfoot the throttle with aluminum clutches you gotta just twist the throttle and just hang on...blip style riding destroys aluminum clutches fast....

http://www.ebay.com/itm/POCKET-BIKE...her_Vehicle_Parts&hash=item2c71d58ac9&vxp=mtr
 

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Thanks you Mr. for suggestions. I agree with you that twisting the throttle often will destroy the AL clutches but the riding style for dirt bikes involves playing with throttle and brakes a lot. We cannot avoid that. It's totally different than riding a street bike. I'll give a try to a steel clutch.
From your explanation I understand that you suggest softer springs and heavier clutch arms in order to obtain clutch engagement at lower rpm. I'll try these. Regards.
 
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