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Discussion Starter #1
In working condition, no crash damage.
Ready to plug and play.

Anyone?
 

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Discussion Starter #2
I put a bid on some on FleaBay.
If not, I'll do the Buy it now then.
 

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Hey Todd why not throw some brembos on that machine for a nice upgrade. That with a RCS corsa corte. You won’t be disappointed I promise.
 

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Discussion Starter #5
Thanks for the replies.
I just picked up a pair of the direct bolt on K9 Monoblock calipers. Great reviews by people. Supposed to be better than the Suzuki branded Brembros also.

I should have then soon.
 
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Discussion Starter #6
I got the pair of K9-L1 Tokico Monoblocs for $140 shipped.
Be here in a week.

After all the reading I've done on this upgrade mod, I'm going to start with my OEM, recall replacement MC and see how it feels and performs before I go with a different MC.
I already have fairly new CoreMoto SS lines, and EBC HH pads up front.
My front feels good now, just looking for a little bit more up there. Actually, just looking for a dcifferent/better feel, as it already stops well now.
 

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This has opinions of the calipers vs others. Be aware that you need a 17 mm MC for good feel. It will be wooden with the usual 19 mm.
 

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Discussion Starter #8
This has opinions of the calipers vs others. Be aware that you need a 17 mm MC for good feel. It will be wooden with the usual 19 mm.
I was hoping you'd chime in Bill!

So my K5 OEM- recall replacemt MC is 19mm?
And by wooden, are you describing a stiffer, block like feel? What does that mean? What is a good Aftermarket, or salvage from another bike replacement MC that is 17mm, that will have the electrodes for my front brake light?

I'm going to try them with my OEM recall-replaced MC and see how that feels.

My brakes are not bad now! And MUCH better when I went to the EBC HH pads.
 

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K9 tokico bore sizes are 30/32
L1 oem brembo are 32/32
M4 brembos are 34/34.
M50 brembos are 30/30.

The stock oem mc on my L1 750 has a 11/16" piston bore. Thats about 17.5mm.
A brembo 19x18/20 is 19mm bore.
Brembo also makes a 17, 15, 14mm MC.

Combinations I have tried
Stock 11/16" MC with oem 32/32- fine
Stock 11/16" with M4 34/34- too much lever travel for my tastes
Brembo 19×18 with 34/34- sweetness
Brembo 19x18 with oem 32/32- ok.
Brembo 17x18 with m50 30/30- also very nice
My next pairing will be the 32/36 GP4rr calipers with the 19x18 brembo mc
(Single caliper setups I will leave out of here)
I have the actual measured weights for the above calipers, too.

I think the stock MC will pair fine with the tokicos if your k5 master cylinder is the same as the l1+ 600/750. If you decide to go aftermarket MC , a 17mm will be likely your best bet.

19mm brembo are set up perfectly for the traditional brembo racing 32/36 caliper bores. They work well with the m4 34/34. Anything smaller and they start to feel a little wooden. They are unusable at the m50 30/30 size where Brembo states are sized for their 17mm MC.

On a side note, tokico caliper castings i have seen IMO have not been as nice as brembo castings. The smoothness and my perceived impression of the density of the material used in brembos i have handled have been noticeably better than tokico's. I have never had a set of the 2009 monoblock tokicos, though. Whether this makes a difference in performance, i do not know.

I like to practice braking hard from triple digits. I do it regularly to get a feel of what the bike wants to do. Good brakes and proficiency in hard braking are more important to me than more engine power at this point.

Good luck with your upgrade!
 

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The K5-K8 MC is 19.07 mm. The K9-L1 MC is 17.48 mm. With regard to the hydraulic ratio (caliper to MC area ratio) you'll find this in many places:
20 or less: Wooden (stiff)
23 : Firm
27 : Sweet spot
30 or more: Soft feel

The OEM K5-K8 ratio is 22.7. It will drop to 21.3 with K9 calipers but rise to 25.3 if you also use the K9 MC. It will be 26.8 with a 17 mm MC.

That doesn't include the mechanical ratio at the lever. It's complicated because it uses the offset (pivot to plunger distance) and the distance from the pivot to the point on the lever where your finger pulls (typically about 135 mm). Such info is hard to come by. My best guess is that with the combined hydraulic & mechanical ratio:
150 or less: Wooden
170 : Firm
200 : Sweet spot
230 or more: Soft feel

Many (most?) aftermarket MCs don't come with a brake light switch and you have to install a pressure activated switch in the hydraulic system. A disadvantage of the pressure switch is that the brake light doesn't come on until pressure builds up whereas a mechanical switch activates the moment the lever moves. Unlike many Brembo MCs, their RCS comes with a mechanical switch that, with minor modification, will plug into the Suzuki brake light switch connector. As I recall, you replace the Brembo bullet connectors with 3/16" tabs. I don't know how active he is any more but SimonKobeJapan used to sell mechanical switches for other Brembo MCs on ebay.
 

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Nissin publishes their total combined ratios (hydraulic x lever ratio) for their master cylinder and various caliper offerings and they are usually between 90 to 115.
Your numbers may be off.

If you are correct on the MC size, I would as you said earlier, consider a smaller MC.

Todd, if you want my 2011 oem recall mc to test, I can mail it to you. I dont want it or need it.

That doesn't include the mechanical ratio at the lever. It's complicated because it uses the offset (pivot to plunger distance) and the distance from the pivot to the point on the lever where your finger pulls (typically about 135 mm). Such info is hard to come by. My best guess is that with the combined hydraulic & mechanical ratio:
150 or less: Wooden
170 : Firm
200 : Sweet spot
230 or more: Soft feel
 

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Reworked RCS brake light switch leads (plugged into the harness connector):

Note that by cutting them off so close to the switch, there's no room for mistakes. As I recall, a new switch is around $25.
 

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Discussion Starter #13
Nissin publishes their total combined ratios (hydraulic x lever ratio) for their master cylinder and various caliper offerings and they are usually between 90 to 115.
Your numbers may be off.

If you are correct on the MC size, I would as you said earlier, consider a smaller MC.

Todd, if you want my 2011 oem recall mc to test, I can mail it to you. I dont want it or need it.
2011 were recalled too? I know my K5 was. Something about the reservoir hose being horizontal and not vertical and cause water/contaminants into the Brake fluid?

Sure, ship them the slow way and I'll pay you for the shipping then?

Is it a 17mm?

** My K9 Monobloc Tokico's came in the mail today!
I'll try to get them on there this week, see how it feels.
 

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Well shoot, I just have the master cylinder body. It is missing the lever and pivot.
I'll snap a pic and let me know if you still want it.
But basically it looks like the picture above. Includes a single stainless banjo but no front side of the handlebar clamp.
 

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Discussion Starter #17
I'm not sure what size recall replacement is actually, Bill I think says 19mm?

11/16" is 17.48mm

I"ll pm you
 

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The K5-K8 MC is 19.07 mm. The K9-L1 MC is 17.48 mm. You'll have to check if the L3 MC is the same as K9-L1. But 11/16" says it is. With it in hand you could check if your front handlebar clamp will transfer over. You could also try a cheap-ass ebay lever to see if you like the feel before getting something decent. But be super careful / short term only there as there've been many problems with locked brakes due to bad levers. It looks like you'll also need a pivot bolt and nut.
 

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Discussion Starter #19
I haven't looked at it, maybe I can just use my lever I have? We'll see.
 

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Discussion Starter #20
View attachment 294547
View attachment 294548

You'll need something like this

I like the ASV brand.
The MC comes with the microswitch.
Needs the front part of the handlebar clamp and bolts.
Single stainless banjo bolt included. No washers.
The one pictured looks like the after the recall MC? the resevoir tube is parellel to the axis of the clamp bolts, not perpendicular?
 
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