Front brake master cylinder for 7/8 inch bars

[DrunkenMistake]

Hey guys, im after a front brake master cylinder for a twin disc sports bike,
Second hand is fine, tidy would be fantastic, has to be something off a high performance 600 or bigger,
I wouldnt like to spend much more than $100ish, but if you have something that tickles my gouche I could wrestle up the funds to go a little bit higher.

Preferably like something with a remote reservoir pot, but im not picky, Ill be needing to find one by Thursday morning so I can pay for it and have it by Saturday (with luck)



EDIT: Must be a complete master cylinder, so Master, Reservoir, and lever and mounting hardware.

254159

[Kickaha]

What bore size?

[ducatilover]

Got a ZZR400k/600D one you can have bro, it might need a new res. cover, but works well.

[tigertim20]

What bore size?

its to replace the stock piece of shit on a 2006/7/8 Hyo GT650R.
I assume it doesnt matter if he goes larger as that will displace more?

[Kickaha]

its to replace the stock piece of shit on a 2006/7/8 Hyo GT650R.
I assume it doesnt matter if he goes larger as that will displace more?

Bigger means less travel and firmer lever, you probably don't want to be to far either side of stock

[ducatilover]

Bigger means less travel and firmer lever, you probably don't want to be to far either side of stock
Wouldn't the swept volume or the master cyl. bore be a bigger influence over just the bore size?

[bogan]

Most masters with similar brake set-up will probably be workable if bore sizes are hard to find. Twin disc with two-pot floating or 4 pot fixed calipers should do the trick. Doug's spare might work pretty good?

Or give bikebusters (i think that's the guy just out of hamilton) a call and he should be able to hook you up.

What's wrong with the original one btw?

[ducatilover]

What's wrong with the original one btw?

Hyosung.


'Nuff said lol

[DrunkenMistake]

What bore size?
I wasnt aware that this would cause a massive problem


Most masters with similar brake set-up will probably be workable if bore sizes are hard to find. Twin disc with two-pot floating or 4 pot fixed calipers should do the trick. Doug's spare might work pretty good?

Or give bikebusters (i think that's the guy just out of hamilton) a call and he should be able to hook you up.

What's wrong with the original one btw?
Its pretty stuffed, I was going to upgrade the master, lines and pads anyway but the master is in need over an overhaul/rebuild and for the frustration and cost of doing it, I might as well start by upgrading the master now..

If I can find out the bore size, could anyone make a recommendation on a master that I should be looking at getting? any help would be fantastic.

[The Lone Rider]

Try

Good Parts LTD
Motorcycle Dismantlers
2 Brackenfield Place
Parklands
Christchurch 8093


Sorry I don't have a number or email. He's on Trademe though.

He went above and beyond in finding me a part that fit what I was working on - off a different model bike. And we did it all be email, and posting parts back and forth until I got one that actually fit.

[bogan]

I wasnt aware that this would cause a massive problem

Get it massively wrong and your brakes will be fucked, lever force is proportional to the bore radius squared, and go too low and you won't displace enough fluid to fully activate the brakes.


Its pretty stuffed, I was going to upgrade the master, lines and pads anyway but the master is in need over an overhaul/rebuild and for the frustration and cost of doing it, I might as well start by upgrading the master now..

If I can find out the bore size, could anyone make a recommendation on a master that I should be looking at getting? any help would be fantastic.

It's a 2008 model, must be made of cheese to need a rebuild by now! I just did my 24yo Honda's master a few months ago, only 40 bucks for a full rebuild too.

What are the symptoms? may be that something else is a problem instead/too. Also, upgrade to full floating calipers is likely to provide a big benefit, and may require another change in master if you do that eventually.

[Kickaha]

I wasnt aware that this would cause a massive problem
It most likely wont but
Go to small and you end up with excess travel as the smaller piston has to travel further to displace the same volume of fluid
Go to big and the lever feels like squeezing a brick as it has to move bugger all to displace the same volume of fluid

Chances are anything with similar brakes will be in the ballpark but it's just something to be aware of, the m/c normally has the size on it

[Steve Gauge]

there should be a number on the side of the master cylinder

[DrunkenMistake]

It most likely wont but
Go to small and you end up with excess travel as the smaller piston has to travel further to displace the same volume of fluid
Go to big and the lever feels like squeezing a brick as it has to move bugger all to displace the same volume of fluid

Chances are anything with similar brakes will be in the ballpark but it's just something to be aware of, the m/c normally has the size on it


there should be a number on the side of the master cylinder

Thanks ill go have a check of it now and see what I can find!

[DrunkenMistake]

Ok had a look, says on the back of the master TCIC 5/8 on a little further on it just says 1
If this means anything

[Kickaha]

Ok had a look, says on the back of the master TCIC 5/8 on a little further on it just says 1
If this means anything

Have you never heard of imperial measurments? 5/8 = 15.875mm

Fuck knows why they use imperial but it isn't an uncommon m/c size

[DrunkenMistake]

Have you never heard of imperial measurments? 5/8 = 15.875mm

Fuck knows why they use imperial but it isn't an uncommon m/c size

figured it was 5/8 of a inch, wasnt sure if this was the bore size or not! haha cheers for your help man.

[DrunkenMistake]

http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/brakes/auction-435212620.htm
Would this do the job, bore size of 14mm

[nzspokes]

http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/brakes/auction-435212620.htm
Would this do the job, bore size of 14mm

No, stick with the stock bore.

Smaller bore will make the lever spongy. Remember its only your hand activating the brake.

Whats wrong with the stock one?

[DrunkenMistake]

No, stick with the stock bore.

Smaller bore will make the lever spongy. Remember its only your hand activating the brake.

Whats wrong with the stock one?

I dont think a 2mm difference in bore size will make a significant difference, MC is first then braided lines and new sintered pads, so by the time all that is done, I doubt ill notice the difference

[DrunkenMistake]

It's a 2008 model, must be made of cheese to need a rebuild by now! I just did my 24yo Honda's master a few months ago, only 40 bucks for a full rebuild too.

What are the symptoms? may be that something else is a problem instead/too. Also, upgrade to full floating calipers is likely to provide a big benefit, and may require another change in master if you do that eventually.

its an 05 model sold in NZ in 08 as new and it is a Hyo..
The rubber boot around the actual piston part has a hole in it, and once you get the boot off.. well shits just fucked..
I done a full strip down and clean out of the callipers yesterday, as I kept losing pressure in the front brake, assumed I had sticky pistons, they were grubby but not that grubby, resembled and spent most of today trying to bleed the system and purge the air out, with fuck all luck, pulled the top banjo out and tested the master, and it simply wasnt pumping out any fluid, and so it went from there.

[nzspokes]

I dont think a 2mm difference in bore size will make a significant difference, MC is first then braided lines and new sintered pads, so by the time all that is done, I doubt ill notice the difference

Its a 13%ish difference which in fluid terms is huge.

[nzspokes]

its an 05 model sold in NZ in 08 as new and it is a Hyo..
The rubber boot around the actual piston part has a hole in it, and once you get the boot off.. well shits just fucked..
I done a full strip down and clean out of the callipers yesterday, as I kept losing pressure in the front brake, assumed I had sticky pistons, they were grubby but not that grubby, resembled and spent most of today trying to bleed the system and purge the air out, with fuck all luck, pulled the top banjo out and tested the master, and it simply wasnt pumping out any fluid, and so it went from there.

So just put a kit in then?

[DrunkenMistake]

Its a 13%ish difference which in fluid terms is huge.
11.811% to be exact,

I feel as though im a broken record here,
I was upgrading the master anyway, rather than get a rebuild kit then replace the master in a couple of weeks I might as well get it now.




Its pretty stuffed, I was going to upgrade the master, lines and pads anyway but the master is in need over an overhaul/rebuild and for the frustration and cost of doing it, I might as well start by upgrading the master now..

[tigertim20]

It's a 2008 model, must be made of cheese to need a rebuild by now! I just did my 24yo Honda's master a few months ago, only 40 bucks for a full rebuild too.

What are the symptoms? may be that something else is a problem instead/too. Also, upgrade to full floating calipers is likely to provide a big benefit, and may require another change in master if you do that eventually.
its a 2006. regoed as an 08. symptoms are brakes suddenly stop working. I suggested he rebuild the calipers, which he has done. then they wouldnt bleed. he said that the issue previously was that he would pull the lever and nothing happened. I thought, well sounds like the MC is up the fuck. So I whipped it off, removed the lever, and the boot that covers the piston had a tear in it. pulled that off, and looked in the depression where the piston in the MC sits, and it was all corroded as fuck. a further inspection showed the corrosion was bad enough that solid shit had flaked off, and was causing blockages. a repair at this point would only result in future problems, and given that the issue is that the brakes dont work when the lever is pulled sometimes, its worth just upgrading.

Have you never heard of imperial measurments? 5/8 = 15.875mm

Fuck knows why they use imperial but it isn't an uncommon m/c size
fucking koreans!



Whats wrong with the stock one?
shits fucked bro.
upgrading size wise (a small amount) wouldnt be a terrible thing, hyo brakes are known for being piss poor even off the showroom floor, a bit more fluid displacement would actually be a good thing on the tank that it is

I dont think a 2mm difference in bore size will make a significant difference, MC is first then braided lines and new sintered pads, so by the time all that is done, I doubt ill notice the difference
2mm in diameter, remember its the surface area of the piston that displaces fluid, calculate the percentage difference and youll find its greater. seeing as your brakes suck shit anyway, going down a size, and reducing the amount of fluid displaced, well, your brakes will be even weaker than they are now

its an 05 model sold in NZ in 08 as new and it is a Hyo..
The rubber boot around the actual piston part has a hole in it, and once you get the boot off.. well shits just fucked..
I done a full strip down and clean out of the callipers yesterday, as I kept losing pressure in the front brake, assumed I had sticky pistons, they were grubby but not that grubby, resembled and spent most of today trying to bleed the system and purge the air out, with fuck all luck, pulled the top banjo out and tested the master, and it simply wasnt pumping out any fluid, and so it went from there.
I ran your vin and I got 06, but i think 05/06 are the same model anyway.

[nzspokes]

shits fucked bro.
upgrading size wise (a small amount) wouldnt be a terrible thing, hyo brakes are known for being piss poor even off the showroom floor, a bit more fluid displacement would actually be a good thing on the tank that it is


Righto, get it now. If it were me then I would get it bored and a stainless liner fitted which can be whatever you want. Then turn up piston to match.

[DrunkenMistake]

I ran your vin and I got 06, but i think 05/06 are the same model anyway.

Same diff, the master varies for the 06 between the one with the silver adjustable brake lever, and the plan old black one like mine, not sure what the full list of differences are, I know for sure the lever sizes and thickness are completely different

[tigertim20]

Righto, get it now. If it were me then I would get it bored and a stainless liner fitted which can be whatever you want. Then turn up piston to match.

this is one option, however he wants a remote reservoir for the look, which is fair enough. I dont see much point in spending money on a part that is shit in the first place.
its gonna cost $50-$100 to mess around with that, and if you increase the bore size, you have to be wary or remaining wall thickness. as well as that, there is an internal snap ring inside the bore, that holds the piston in (the piston is stepped) and prevents it from coming out further to prevent fluid leakage. machining the grove would be a pain in the ass.

For the cost he can just upgrade to a nicer item with the remote reservoir he wants anyway

[theseekerfinds]

I have used Good Spares and agree they are a helpful bunch down there.. I have also used Sweetstreet for spares and found them helpful too.. here's a Ducati 748 setup they have on trademe currently if that helps..

http://www.trademe.co.nz/motors/motorbikes/parts-for-sale/brakes/auction-436595597.htm

[Tony.OK]

Don't forget that different masters may have different banjo bolt sizes and pitch too, could mean having to need custom made brake lines to fit each end once changed................more cost.

[hayd3n]

its a 2006. regoed as an 08. symptoms are brakes suddenly stop working. I suggested he rebuild the calipers, which he has done. then they wouldnt bleed.

so you replaced parts in the caliper'?
or just cleaned?

[tigertim20]

so you replaced parts in the caliper'?
or just cleaned?

he bought o rings to replace the existing ones, but when it was apart, turns out the ones he bought were the wrong type. the shop he would have got new ones from isnt open for another few days. the existing ones were in good nick anyway (as youd expect on a bike thats only less than 10,000km old.)

if you read through, youll see that the caliper isnt the problem anyway, so the point is moot

[hayd3n]

he bought o rings to replace the existing ones, but when it was apart, turns out the ones he bought were the wrong type. the shop he would have got new ones from isnt open for another few days. the existing ones were in good nick anyway (as youd expect on a bike thats only less than 10,000km old.)

if you read through, youll see that the caliper isnt the problem anyway, so the point is moot
i would suggest wilsons bros for orings ,
for a 3 year old bike it would almost be under a warrenty? especially since its a very important part of the bike?

[tigertim20]

i would suggest wilsons bros for orings ,
for a 3 year old bike it would almost be under a warrenty? especially since its a very important part of the bike?

its a 6 year old bike, its an 05/06.
but like I said, he doesnt need orings anyway, that is not the problem

[DrunkenMistake]

I dont need O rings the callipers are fine the vin shows up as factory built in September 2006, sold new in NZ in 08, Im the second owner, so no,
The actual MC is roasty toasty

[DrunkenMistake]

Got a SV1000 Master cylinder with the remote res and lever, with a 5/8 bore size.

[ducatilover]

Should have waited for me to dig mine out :facepalm:

[DrunkenMistake]

Should have waited for me to dig mine out :facepalm:

Lol its all good! this is one of the ones I have been head hunting for on ebay anyways, found it for about the same price as it would have cost me on there so no issues, get it on Friday.

[ducatilover]

You could've had a free one though lol
Hopefully it works bro

[DrunkenMistake]

You could've had a free one though lol
Hopefully it works bro

Ill take it anyways? :D


I have a suspicion the banjo bolt pitch is 1.25mm for the SV and 1.00mm for the Hyo, been the case ill just have to get a new Banjo bolt with the correct pitch.

[hayd3n]

Ill take it anyways? :D


I have a suspicion the banjo bolt pitch is 1.25mm for the SV and 1.00mm for the Hyo, been the case ill just have to get a new Banjo bolt with the correct pitch.

first golf and now cricket?

[RDjase]

Have you never heard of imperial measurments? 5/8 = 15.875mm

Fuck knows why they use imperial but it isn't an uncommon m/c size

What size rims are on your bike kick?

I work on heaps of American machinery and its full of UNC bolts, NPT threads and imperial pnuematic tube. Talk about confuse the young blood. One young fullah I had helping me was measuring things in centimeters ! He said that how they taught him at high school engineering FFS

[ducatilover]

Ill take it anyways? :D


I have a suspicion the banjo bolt pitch is 1.25mm for the SV and 1.00mm for the Hyo, been the case ill just have to get a new Banjo bolt with the correct pitch.
I'll dig it out :2thumbsup