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79 Cent mod causing clutch slippage?

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Hi there,

I have some problems with my clutch slipping in some situations.

I installed the 79 cent mod some time ago and was wondering if it might be the cause of this problem. Essentially it does also take some spring load from the clutch plates.. This might cause the clutch to slip in some situations.

Is my logic correct?

Chris

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Hi there,

I have some problems with my clutch slipping in some situations.

I installed the 79 cent mod some time ago and was wondering if it might be the cause of this problem. Essentially it does also take some spring load from the clutch plates.. This might cause the clutch to slip in some situations.

Is my logic correct?

Chris

Is this the mod that puts washers under the clutch springs?

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Hi there,

I have some problems with my clutch slipping in some situations.

I installed the 79 cent mod some time ago and was wondering if it might be the cause of this problem. Essentially it does also take some spring load from the clutch plates.. This might cause the clutch to slip in some situations.

Is my logic correct?

Chris

How old are your clutch and friction plates?

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Hi there,

I have some problems with my clutch slipping in some situations.

I installed the 79 cent mod some time ago and was wondering if it might be the cause of this problem. Essentially it does also take some spring load from the clutch plates.. This might cause the clutch to slip in some situations.

Is my logic correct?

Chris

Theoretically, adding the washers adds to the clamping force applied to the clutch plates. So, no, your logic is incorrect.

If your clutch is slipping you could have one of several problems;

A) The clutch is not correctly adjusted. You should have at least a half inch of free play at the lever. If there is no free play, it needs to be adjusted.

:bonk: The clutch is worn out.

C) The clutch springs may have been overheated and partially lost some of their temper.

D) The clutch friction plates may have been 'poisoned' by oil additives, incorrect oil selection, or not changing the oil frequently enough.

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I don't think the washer mod adds to clutch spring compression. from what I remember when trying it, the washers increase the cavity length for the spring and reduce the compression force.

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I don't think the washer mod adds to clutch spring compression. from what I remember when trying it, the washers increase the cavity length for the spring and reduce the compression force.

So where exactly are these washers being placed?

I've never heard of the '79 cent mod'. Sounds kinda' hokey.

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OK, finally found the details about this mod. So if your clutch is slipping after doing this 'mod', I would suggest you remove the washers. If it still slips after that, you need to make sure you have enough free play at the lever (at least 1/2"). If it's still slipping, you probably need new friction plates and or springs.

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Thanks folks.

I wasn´t clear about the "washers add / reduce spring force" topic.

I will remove the washers and see what happens.

The clutch has about 400 miles on it. Although there was some slippage I don´t think that the clutch should be that worn. Add least there is no wear to measure..

Chris

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I recall the "washer fix" being used to reduce a "grabby" clutch. There are numerous posts on the topic. I tried it, but it didn't solve my problem on my WR. I've never experienced a "grabby" clutch and a slipping clutch at the same time.

Do you have a YZ or a WR? I've been running YZ cutch springs in my WR with an inexpensive set of TUSK clutch and friction plates. Been holding up well and haven't had any sense of the clutch slipping. I had tried the TUSK heavy duty springs, but they had way too heavy of a clutch pull. My wrist would be sore and tired after riding an hour. I even added the longer 1999 YZ400F clutch arm, but it was still too stiff. The YZ springs with the longer clutch arm feels about right.

Don't know how much it really helps, but I also drilled the clutch hub per the FAQ to improve flow of oil to clutch plates.

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i remember dirt bike magazine did a cheapfix article and talked about using spark plug washers under the clutch springs to get some life out of a slipping clutch which would tell me this increases clamping force

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Those would be larger washers that actually are at least as big of a diameter as the spring. They would increase the pre-load on the spring.

For the "washer mod" to address a "graby" clutch, the washers are smaller than the ID of the springs (6mm, flat wahsers) so the heads of the bolts ride higher and the cavity for the spring is increased. This decreases the preload on the springs.

It worked for me for a little while, then I replaced clutch and friction plates and went with YZ springs. Now, before the first ride of the day, I always warm up the motor in neutral, lean the bike over a little to the right (clutch side), pull in the clutch, and give it a couple of revs. Then when I drop it it gear, it never wants to grab and stall. I need a new basket. Mine's a little notched.

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I recall the "washer fix" being used to reduce a "grabby" clutch. There are numerous posts on the topic. I tried it, but it didn't solve my problem on my WR. I've never experienced a "grabby" clutch and a slipping clutch at the same time.

Do you have a YZ or a WR? I've been running YZ cutch springs in my WR with an inexpensive set of TUSK clutch and friction plates. Been holding up well and haven't had any sense of the clutch slipping. I had tried the TUSK heavy duty springs, but they had way too heavy of a clutch pull. My wrist would be sore and tired after riding an hour. I even added the longer 1999 YZ400F clutch arm, but it was still too stiff. The YZ springs with the longer clutch arm feels about right.

Don't know how much it really helps, but I also drilled the clutch hub per the FAQ to improve flow of oil to clutch plates.

I´m using almost new (see above) EBC clutch and friction plates with new original springs on my WR250F.

I also tried the heavy duty springs from EBC. They ruined this trip for me and my friends. These are definitely not the springs one wants to use for some hard-enduro :bonk:

I will remove the 79 cent fix and see what happens.

Chris

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OK, well first of all the "Free Clutch Mod" is a bunch of folklore hooey- it is just ridiculous, it lessens the spring force on the clutch plates, and the moron who thought of the idea is an idiot that should not be allowed to own tools. (I should say how I really feel, LOL)

The only reason the mod could allow the clutch to open further, and that is the intended result, is if the springs were becoming coil bound. However, if you investigate, you will see that the OEM springs simply do not become coil bound.

This is not to say that some people might add the washers and then think/free their clutch dragging is gone. IF the clutch dragging were to disappear, it is because their clutch slips easier than previous and sometimes, slipping the clutch will heat up the plates and helps clean the plates of sticky goo.

If you have a dragging clutch, the cause is simply that your clutch plates have sticky goo on them. You can try cleaning the plates or soaking the plates in oil, or give the bike a good "second or third gear holeshot" type of clutch heating up which can help for the afternoon, but most likely, you need to get new plates.

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