CBR600 clutch for CBR400. Possible ?

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PARUS
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CBR600 clutch for CBR400. Possible ?

Post by PARUS » Fri Jul 22, 2011 2:47 pm

Just curious - have anybody tried to fit CBR600RR latest years clutch to CBR400?

amorti
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Re: CBR600 clutch for CBR400. Possible ?

Post by amorti » Fri Jul 22, 2011 5:13 pm

I tried to fit a CBR600F1 clutch to a CB-1, as I had discovered that the plates and springs share a part number.

The primary drive ratio is very different though, and I expect you would have the same problem on your proposed swap. What benefit do you seek? The CBR400 clutch is nearly identical to the CBR600F1 clutch (just a different primary gear on the back of it), which had to handle around 85hp-90hp, so it is unlikely to ever prove the weak link in your engine.

matt69
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Re: CBR600 clutch for CBR400. Possible ?

Post by matt69 » Sat Jul 23, 2011 4:09 am

amorti wrote:I tried to fit a CBR600F1 clutch to a CB-1, as I had discovered that the plates and springs share a part number.

The primary drive ratio is very different though, and I expect you would have the same problem on your proposed swap. What benefit do you seek? The CBR400 clutch is nearly identical to the CBR600F1 clutch (just a different primary gear on the back of it), which had to handle around 85hp-90hp, so it is unlikely to ever prove the weak link in your engine.
Slipper clutch I think. I'd love to do this on mine as well, but from discussions on here the CBX750 clutch is the way to go for this.

I haven't done it, but next year when i do the engine I'll try it out. Finally getting into rebuilding my wrecked race bike this weekend. Changing the bent frame and swingarm.

Matt

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Re: CBR600 clutch for CBR400. Possible ?

Post by amorti » Sat Jul 23, 2011 9:11 am

Clutch from a CBX750? Why is that then? Are we both thinking about the cbx750f from about 1984-5? my dad has one of those in pieces in his shed with a dead engine. I rode it before it gave up, don't specifcally remember the clutch being "special"?

PARUS
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Re: CBR600 clutch for CBR400. Possible ?

Post by PARUS » Sun Jul 24, 2011 8:40 am

Yes, the main point is fit slippery clutch. Has cbx750f slipperry clutch ? I think it's not.

matt69
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Re: CBR600 clutch for CBR400. Possible ?

Post by matt69 » Sun Jul 24, 2011 9:25 am

PARUS wrote:Yes, the main point is fit slippery clutch. Has cbx750f slipperry clutch ? I think it's not.
Yep parus, the RC17 which is one of the CBX750 models has got a sprag clutch, just like the NC30, which is a primitive form of slipper clutch. It is however hydraulic and I'm not sure how one would go converting it to cable or fitting a hydraulic cluch to the NC29.

The NC30 sprag clutch certainly helps on the tracks I race on as I have to slip the clutch myself heading into turns, where when I was on a NC30 race bike you could just bang down a gear and there would be a little chirp as the rear wheel locked and then the clutch slipped.

Matt

PARUS
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Re: CBR600 clutch for CBR400. Possible ?

Post by PARUS » Sun Jul 24, 2011 10:25 pm

matt69 wrote:
PARUS wrote:Yes, the main point is fit slippery clutch. Has cbx750f slipperry clutch ? I think it's not.
Yep parus, the RC17 which is one of the CBX750 models has got a sprag clutch, just like the NC30, which is a primitive form of slipper clutch. It is however hydraulic and I'm not sure how one would go converting it to cable or fitting a hydraulic cluch to the NC29.

The NC30 sprag clutch certainly helps on the tracks I race on as I have to slip the clutch myself heading into turns, where when I was on a NC30 race bike you could just bang down a gear and there would be a little chirp as the rear wheel locked and then the clutch slipped.

Matt
Thank Matt for details. I don't know about CBX750 clutch.

As you mentioned NC30 also has sprag clutch does anybody thinking about fitting NC30 clutch? Unfortunatelly there is not too much vfr400 engine to make measurement.

matt69
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Re: CBR600 clutch for CBR400. Possible ?

Post by matt69 » Mon Jul 25, 2011 8:27 am

[/quote]

Thank Matt for details. I don't know about CBX750 clutch.

As you mentioned NC30 also has sprag clutch does anybody thinking about fitting NC30 clutch? Unfortunatelly there is not too much vfr400 engine to make measurement.[/quote]

Parus,

I'm quite sure the NC30 clutch doesn't fit.

Matt

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Re: CBR600 clutch for CBR400. Possible ?

Post by kiwi racer » Mon Aug 01, 2011 8:30 am

CBX750 can be made to fit ok. Slipper type allowing 3 of 7 to release under hard loading. Hydr to cable convertion easy enuff but you need to fuss a bit. Good hard assy . I suggest use the 750 centre to original 400 housing.

matt69
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Re: CBR600 clutch for CBR400. Possible ?

Post by matt69 » Mon Aug 01, 2011 9:10 am

kiwi racer wrote:CBX750 can be made to fit ok. Slipper type allowing 3 of 7 to release under hard loading. Hydr to cable convertion easy enuff but you need to fuss a bit. Good hard assy . I suggest use the 750 centre to original 400 housing.
Thanks Paul, I think you were the person who mentioned this originally.

Matt

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