Are aftermarket clutches bad for our transmissions?

JDMpo0kie

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i really want to reinstall my FX300 clutch and single mass fywheel but I’m getting a lot of different views on upgraded clutches. Can anyone verify this?
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amirza786

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If the clutch locks you out of a gear or gears (clutch drag), than it could cause damage to the synchros. Other than that, I have not heard of an after market clutch damaging a transmission. Probably your mechanic can give you better advice on this
 

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Well, from OEM to Fx300 you go from a spring damped fly wheel to a spring damped hub. You still have spring damped drive line protection.
So I'm pretty sure any difference between the two systems would be much smaller than the way the clutch was used, or abused.
 

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It can cause more wear on your transmission. Engine crank rotation > transmission > clutch >wheel.

If the wheels spin, there is less strain on the clutch since more rotational inertia is being released through the wheel spinning. If the wheels don't spin due to good contact, more strain is put on clutch and can cause slippage (seen on hub dynos vs wheel/roll dynos). That is why lugging causes clutch clippage (all that power w/o wheel spin)

Ultimately, fixing clutch slipping will put more strain on your transmission, given that you have no wheelspin.

IMO, keep your OEM clutch installed until it wears out. You already have the replacement. It'll be a shame to see a wasted clutch and paying for all that labor when the clutch is already working perfectly.

Save yourself hundreds of dollars on someone not needed and treat yourself and significant other on a nice getaway with the money you just saved.
 
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amirza786

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It can cause more wear on your transmission. Engine crank rotation > transmission > clutch >wheel.

If the wheels spin, there is less strain on the clutch since more rotational inertia is being released through the wheel spinning. If the wheels don't spin due to good contact, more strain is put on clutch and can cause slippage (seen on hub dynos vs wheel/roll dynos).

Fixing clutch slipping will put more strain on your transmission, given that you have no wheelspin.

IMO, keep your OEM clutch installed until it wears out. You already have the replacement. It'll be a shame to see a wasted clutch and paying for all that labor when the clutch is already working perfectly.
I would agree with this assessment on keeping the OEM clutch for now. You can prevent clutch slippage by not doing WOT at low rpm/high engine loads and at 5th and 6th gears when using Map 3 in Sports mode
 


Andre80

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I would agree with this assessment on keeping the OEM clutch for now. You can prevent clutch slippage by not doing WOT at low rpm/high engine loads and at 5th and 6th gears when using Map 3 in Sports mode
this should be highlighted
all clutches wear out, even stock, the duration is determined by how it is used

I've seen clutches last 60000km and another 250000km on the same engine, but different driver
 
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JDMpo0kie

JDMpo0kie

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I would agree with this assessment on keeping the OEM clutch for now. You can prevent clutch slippage by not doing WOT at low rpm/high engine loads and at 5th and 6th gears when using Map 3 in Sports mode
I have 2 oem clutch and flywheels. My old one from my blown motor and the one installed on my new motor. Haha. Okay thanks for the advice. I’ll keep my roll races at least 3-3.5k rpm and up.
 
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JDMpo0kie

JDMpo0kie

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this should be highlighted
all clutches wear out, even stock, the duration is determined by how it is used

I've seen clutches last 60000km and another 250000km on the same engine, but different driver
Yeah I drove my Sinhard everyday since my break in with +9psi on Hondata and not 1 slip and when they took a look at my clutch, they said my clutch looks awesome and asked why I was swapping it. I told them I’m going to be getting a custom tune and they just continued working lol.
 

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Yeah I drove my Sinhard everyday since my break in with +9psi on Hondata and not 1 slip and when they took a look at my clutch, they said my clutch looks awesome and asked why I was swapping it. I told them I’m going to be getting a custom tune and they just continued working lol.
I'm on the +9 Hondata also, no slipping so far at all
 

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lots and lots of miles(90k km) on clutch masters 300 using stock dmf. other than learning to leave the line without it shuddering i have had no lockout or slippage.
no failures. i did cdv delete too.
i DRIVE it too. not just baby it. my stock clutch was slipping at 5k if that says anythong about how i drive it.

auto cross.. track days. tsp1. etc.
 


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One thing I noticed which is concerning is the amount of members talking of clutch slippage. Stock clutches will slip when lugging the engine with this amount of torque. While all the talk is about the clutch and upgrading it, people need to understand that lugging is just as bad on the engine itself as it is on the clutch.

Save your engine, don't lug it. Engines don't come cheap
 

caspar21

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One thing I noticed which is concerning is the amount of members talking of clutch slippage. Stock clutches will slip when lugging the engine with this amount of torque. While all the talk is about the clutch and upgrading it, people need to understand that lugging is just as bad on the engine itself as it is on the clutch.

Save your engine, don't lug it. Engines don't come cheap
the only real concern other than the clutch is the rods. the si rods handle lugging no problem. i did the clutch because i wanted to use the low power band without smelling clutch. no rod problems or anything.
 

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lots and lots of miles(90k km) on clutch masters 300 using stock dmf. other than learning to leave the line without it shuddering i have had no lockout or slippage.
no failures. i did cdv delete too.
i DRIVE it too. not just baby it. my stock clutch was slipping at 5k if that says anythong about how i drive it.

auto cross.. track days. tsp1. etc.
why beat on a civic like this?
 

Rich19Si

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the only real concern other than the clutch is the rods. the si rods handle lugging no problem. i did the clutch because i wanted to use the low power band without smelling clutch. no rod problems or anything.
The problems you get with lugging is not something you'll get suddenly. Engine longetivity suffers greatly with lugging. It's not one of those "I lug my engine all the time and have no issues with 25k miles".

When I mention that it was detrimental to engine health overall including rods, pistons, etc. Si engines are just like any other engine, nothing special. Lugging is harmful to it whether you have problems or not at the moment. It could mean the difference of your engine lasting hundreds of thousands of miles to piston rings wearing out in 100k.
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