F4i brakes
 

I was thinking about getting some f4i calipers but wanted to run them with a radial master. will a new 1000rr master be ok? is the stroke to big? I ran across a link to one of the other vtr forums where a guy had made a spreadsheet with the different braking options and their calculated pressure ratios but now can't seem to find it. Do any of you who have done brake mods have any thoughts on this or what mc I should use for the f4i calipers?

2000th Post!
 

I just used the F4i M/C with the F4i calipers. Worked great on the F4i.... also works great on my VTR... go figure. :D

no way really? I wonder why? no actually that's my current back up plan. congrats on post 2000

I am running 98 900RR calipers (same as F4i) and have it mated to a NIssin raidal MC from a 2006 ZX-6R (which I beleive is the same as CBRs and GSX-Rs) asnd the set-up is awesome. Stick some good pads in there and brace yourself!!!!!

I had clearance problems with the 1000RR master cylinder so that one's no-go.

Mine is mounted to Helibars and it's a tight fit, but it can be made to work

I got the calipers and they have ss lines on them, I'm now wondering what pads to put on them. I'm looking for good street brakes not race brakes that I have to warm up or anything, cheaper is better. Any ideas? Greg was that clearance issues with an otherwise stock set up? how much of clearance issues?

I had HRC hard bite pads which were amazing but they are $$$$$. MY next swap, I am going to Vesrah RJL's, they come very highly recommended and cost about $80 for front end.

Well I have a set of RJL's, give me a couple of weeks and I'll let you know how they work

+1 on the RJL pads. a great street & trackday pad.

tim

I got EBC HH pads on mine and like them lots. They were about $60 for the front from a local shop in Phoenix.

Clearance problems were with aftermarket bars and the 1000RR forks. Even with fully adjustable clip-ons I couldn't get it so it wouldn't touch the tank, fairing, or both.

My buddy is running a 1000RR master on VFR bars, no clearance issues. He's got a pair of Tokico 6 pots, and although the braking action is good, the feel is rather spongy.

It was me who did the spreadsheet, but I took all the sizes off the threads I found on this site:D

I dont know what diameter the 1000rr master cylinder is, but if you look in one of my follow up replies there is some interesting data logging results from a UK bike magazine on the deceptive performance from a lager bore M/C.............deceptive in that the barkes felt stronger [as the lever feel was good] but teh stopping distance was longer!

Here is the link to the UK forum thread if you are interested.

http://www.vtr1000.org/phpBB3/viewtopic.php?f=9&t=15494

if you know the bore of the 1000RR M/C I can update the spreadsheet, or you can look for the closest similar size

So what I'm gathering from this thread is that I'd get the most stopping power from the f4i calipers and stock MC? Are the banjo bolts the same that I could use my current lines?
Kudos on the spreadsheet by the way, very good info to have at hand. :)

yes but even more lever travel than stock. There's a sweet spot between feel and travel that's right for each person, stock mc with f4i brakes will give the most actual stopping power but you probably want less lever travel and a slightly firmer feel.

I can also vouch for the stock F4i master cylinder doing the job.

Feel and stopping power is excellent.

It bolts up with no clearance issues.

Your brake lever will fit (especially handy if you have Pazzo's or similar).

Existing brake lines will fit if you have braided lines.

Pretty good option I reckon. ;)

any body know anything about these MCs? I run an SP1 MC & f4i calipers but want more feel, an easier pull & eq power...

http://cgi.ebay.com/ebaymotors/Front...item56308656c9

That is also my view.........best compromise would be F4i caliper & M/C together.

I dont know what the lever travel is with standard M/C and these calipers, for sure it will be longer than standard, but I dont know if it is still OK. I think there are people out there who have this set up, so perhaps they can comment.......for sure they will have the best hydraulic advantage so should have good stopping power, but perhaps less feel.

Don`t forget when it comes to MC, piston diameter is NOT the only factor to consider, there is also the matter of leverage afforded by the pivot distance. This is why, for example, Brembo makes three radial MCs with 19 mm pistons, the 19x16, 19x18 and 19x20. The 16 gives the most leverage at the cost of increased lever travel whereas the 20 lies at the other extreme, with the shortest lever travel and least leverage. Having run a Nissin 19 mm radial MC (from a 2006 ZX-6R) with 900RR calipers (same as F4i), I can vouch that this set-up is significantly stronger than the SP2 MC I ran previously. I can now lock the front wheel at will,and am still using the stock 296 mm rotors. The only reason I can see for NOT goign to this set-up has to do with fitment issues. Trust me, if you can make it fit, you will NOT regret it!!!!!!!

Skokie, I was wondering the same thing. I know there cheap korean or chinese brembo knock offs and I've heard the super cheap ones are crap but I don't know about the larger diameter more expensive ones. Supposedly the casting is better. I know there are a lot of things out there that have been stolen and then duplicated at low cost in asia that are ok and sometimes far superior products than the original (some of the Iclones are ridiculously awesome) but some of that stuff is total crap to.

I personally wouldn`t go there. BTW, if you want an easier pull, steer clear of a 19x20 (see my previous post).

Mikstr............spot on with the mechanical leverage adding [or subtracting] to the hydraulic leverage. I made the assumption that the lever ratio was the same as I had no data to use [and with the honda non radial M/Cs that use the same lever it was a fair assumption].
If i had good data on the lever ratios I was going to add that to the calculation so I could convert force exerted by your hand at a set point on the lever to caliper force exerted on the pads. ......... and I did think about showing the lever movement to displace the caliper pistons as well, but I remembered that I need to get a life!

and thanks for answering the question I didnt ask yet........"what does 19x20 mean?" I was wondering about that.

In the expression 19x20, the first number refers to the piston size and I believe the second refers to the distance away from the fulcrum at which the pressure is applied (in mm?). So, a 19x16 would give you more mechanical advantage (but require greater travel) than a 19x20, for example. Brembo also make some that are 16x??, and this indicates a 16 mm piston.

Hope that helps :)

Thanks for bringing that up mikstr, I think I knew that in the back of my mind but had failed to actually think about it. Along the same line I think we need to take into account the difference in mechanical advantage due to rider hand position. I propose for easier math we assume a single point of contact and measure the distance from the middle finger to the pivot point and use that number ( does everyone use there middle finger to brake?). Once the SI spladle standard for measuring braking lever mechanical advantage is adopted it will all be much simpler. Also on a serious note more lever travel leads to a slower reaction time and this needs to be taken into account for total stopping distance, a tenth of a second at 60 mph is almost 9 feet